Go to a  "printer friendly" view of this message which allow an easy print Printer-friendly copy Go to the page which allows you to send this topic link and a message to a friend Email this topic to a friend
Forums Lobby GET TO KNOW YOUR CAMERA & MASTER IT Nikon D90/D80/D70 (Public) topic #223238
View in linear mode

Subject: "D90 Photographic Dynamic Range - Surprising Result" Previous topic | Next topic
bclaff Silver Member Awarded for multiple contributions for the Resources Nikonian since 26th Oct 2004Mon 20-Oct-08 10:22 PM
9681 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
"D90 Photographic Dynamic Range - Surprising Result"


Vancouver (WA USA not Canada), US
          

Photographic Dynamic Range Defined

Photographic dynamic range is a practical measure of the ability of the sensor to capture an image that will have acceptable noise at a normal enlargement and viewing distance.

This is distinctly different from dynamic range as defined in engineering terms.

How Photographic Dynamic Range is Determined

The raw data from a series of dark images is analyzed for Signal to Noise Ratio (SNR).

The SNR values are adjusted for the Circle of Confusion (CoC) that is appropriate for the sensor size.

The signal value at which this corrected SNR crosses the value of 20 is used to compute a Dynamic Range (DR) value as an Exposure Value (EV).

Results

The following updated results include data for the D90.

The initial results were surprising so I acquired two additional datasets that confirm the findings.



The D90 has better Photographic Dynamic Range than the D300 at every ISO.
And the Photographic Dynamic Range even exceeds the D3 and D700 at ISO 100 (but not above ISO 200).


Bill

Visit me at My site

Attachment #1, (jpg file)

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

Replies to this topic
Subject Author Message Date ID
Reply message RE: D90 Photographic Dynamic Range - Surprising Result
Graceland Silver Member
20th Oct 2008
1
Reply message RE: D90 Photographic Dynamic Range - Surprising Result
bclaff Silver Member
21st Oct 2008
5
Reply message RE: D90 Photographic Dynamic Range - Surprising Result
lofling
21st Oct 2008
20
Reply message RE: D90 Photographic Dynamic Range - Surprising Result
RichBeau
20th Oct 2008
2
Reply message RE: D90 Photographic Dynamic Range - Surprising Result
Aqualung Silver Member
21st Oct 2008
3
     Reply message RE: D90 Photographic Dynamic Range - Surprising Result
bclaff Silver Member
21st Oct 2008
4
          Reply message RE: D90 Photographic Dynamic Range - Surprising Result
jaysd200
21st Oct 2008
6
               Reply message RE: D90 Photographic Dynamic Range - Surprising Result
bclaff Silver Member
21st Oct 2008
7
                    Reply message RE: D90 Photographic Dynamic Range - Surprising Result
jon_b
21st Oct 2008
8
                         Reply message RE: D90 Photographic Dynamic Range - Surprising Result
bclaff Silver Member
21st Oct 2008
10
Reply message RE: D90 Photographic Dynamic Range - Surprising Result
Tony_Jeffree
21st Oct 2008
9
Reply message RE: D90 Photographic Dynamic Range - Surprising Result
bclaff Silver Member
21st Oct 2008
11
     Reply message RE: D90 Photographic Dynamic Range - Surprising Result
Tony_Jeffree
21st Oct 2008
12
          Reply message RE: D90 Photographic Dynamic Range - Surprising Result
bclaff Silver Member
21st Oct 2008
14
               Reply message RE: D90 Photographic Dynamic Range - Surprising Result
Tony_Jeffree
21st Oct 2008
15
Reply message RE: D90 Photographic Dynamic Range - Surprising Result
MstrBones Silver Member
21st Oct 2008
13
Reply message RE: D90 Photographic Dynamic Range - Surprising Result
bclaff Silver Member
21st Oct 2008
16
     Reply message RE: D90 Photographic Dynamic Range - Surprising Result
Tony_Jeffree
21st Oct 2008
17
     Reply message RE: D90 Photographic Dynamic Range - Surprising Result
MstrBones Silver Member
21st Oct 2008
18
          Reply message RE: D90 Photographic Dynamic Range - Surprising Result
bclaff Silver Member
21st Oct 2008
19
               Reply message RE: D90 Photographic Dynamic Range - Surprising Result
MstrBones Silver Member
21st Oct 2008
21
                    Reply message RE: D90 Photographic Dynamic Range - Surprising Result
bclaff Silver Member
22nd Oct 2008
22
                    Reply message RE: D90 Photographic Dynamic Range - Surprising Result
ChrisLilley
25th Nov 2008
37
Reply message RE: D90 Photographic Dynamic Range - Surprising Result
C2020
27th Oct 2008
23
Reply message RE: D90 Photographic Dynamic Range - Surprising Result
bclaff Silver Member
27th Oct 2008
24
Reply message RE: D90 Photographic Dynamic Range - Surprising Result
purdyd
30th Oct 2008
25
Reply message RE: D90 Photographic Dynamic Range - Surprising Result
bclaff Silver Member
30th Oct 2008
26
     Reply message RE: D90 Photographic Dynamic Range - Surprising Result
purdyd
30th Oct 2008
27
Reply message RE: D90 Photographic Dynamic Range - Surprising Result
stevesummerford
31st Oct 2008
28
Reply message RE: D90 Photographic Dynamic Range - Surprising Result
bclaff Silver Member
31st Oct 2008
29
     Reply message RE: D90 Photographic Dynamic Range - Surprising Result
stevesummerford
01st Nov 2008
30
     Reply message RE: D90 Photographic Dynamic Range - Surprising Result
purdyd
01st Nov 2008
31
     Reply message RE: D90 Photographic Dynamic Range - Surprising Result
bclaff Silver Member
01st Nov 2008
32
          Reply message RE: D90 Photographic Dynamic Range - Surprising Result
purdyd
01st Nov 2008
33
               Reply message RE: D90 Photographic Dynamic Range - Surprising Result
bclaff Silver Member
01st Nov 2008
34
               Reply message RE: D90 Photographic Dynamic Range - Surprising Result
bclaff Silver Member
01st Nov 2008
35
                    Reply message RE: D90 Photographic Dynamic Range - Surprising Result
kjyuan
24th Nov 2008
36
     Reply message RE: D90 Photographic Dynamic Range - Surprising Result
rjackson43
10th Feb 2009
54
          Reply message RE: D90 Photographic Dynamic Range - Surprising Result
bclaff Silver Member
10th Feb 2009
55
               Reply message RE: D90 Photographic Dynamic Range - Surprising Result
rjackson43
10th Feb 2009
56
                    Reply message RE: D90 Photographic Dynamic Range - Surprising Result
bclaff Silver Member
10th Feb 2009
57
Reply message RE: D90 Photographic Dynamic Range - Surprising Result
ChrisLilley
25th Nov 2008
38
Reply message RE: D90 Photographic Dynamic Range - Surprising Result
bclaff Silver Member
25th Nov 2008
39
     Reply message RE: D90 Photographic Dynamic Range - Surprising Result
ChrisLilley
26th Nov 2008
40
          Reply message RE: D90 Photographic Dynamic Range - Surprising Result
bclaff Silver Member
26th Nov 2008
41
               Reply message RE: D90 Photographic Dynamic Range - Surprising Result
ChrisLilley
30th Nov 2008
42
                    Reply message RE: D90 Photographic Dynamic Range - Surprising Result
bclaff Silver Member
30th Nov 2008
43
                         Reply message ntxt
Sandor
19th Jan 2009
44
Reply message RE: D90 Photographic Dynamic Range - Surprising Result
Sandor
19th Jan 2009
45
Reply message RE: D90 Photographic Dynamic Range - Surprising Result
ChrisLilley
19th Jan 2009
46
Reply message RE: D90 Photographic Dynamic Range - Surprising Result
arcusmay
19th Jan 2009
47
     Reply message RE: D90 Photographic Dynamic Range - Surprising Result
bclaff Silver Member
23rd Jan 2009
49
Reply message RE: D90 Photographic Dynamic Range - Surprising Result
bclaff Silver Member
23rd Jan 2009
48
     Reply message RE: D90 Photographic Dynamic Range - Surprising Result
Sandor
27th Jan 2009
52
Reply message RE: D90 Photographic Dynamic Range - Surprising Result
davidziff2 Silver Member
24th Jan 2009
50
Reply message RE: D90 Photographic Dynamic Range - Surprising Result
bclaff Silver Member
24th Jan 2009
51
     Reply message RE: D90 Photographic Dynamic Range - Surprising Result
davidziff2 Silver Member
10th Feb 2009
53

Graceland Silver Member Nikonian since 19th Mar 2006Mon 20-Oct-08 11:19 PM
1515 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#1. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 0


Memphis, US
          

Bill...thanks for posting this. I have learned a lot from your various posts as well as your website since I joined Nikonians. As I am in the process of deciding on an upgrade to either the D90 or the D300 (from my current D80) this info is very timely. So am I correct in my muddled technically challenged interpretation to conclude from this chart that (all other factors being equal) the D90 appears to perform significantly better (e.g. at capturing a wider dynamic range)than the D80 in general low-light shooting throughout the ISO range of 100-3200. It also appears to be slightly better than the D300. Is that a correct reading? Second, would I be correct to also conclude that this translates to lower noise levels at all ISO's (again, assuming all else to be equal)? Again, thanks for your very informative posts. I have come to consider you and a few others here as my "virtual" mentors as I try to learn digital photography. Oh yeah...if I happen to win the powerball, I will compensate all my virtual mentors accordingly!!

Jeff

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

    
bclaff Silver Member Awarded for multiple contributions for the Resources Nikonian since 26th Oct 2004Tue 21-Oct-08 12:13 AM
9681 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#5. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 1


Vancouver (WA USA not Canada), US
          

Jeff,

Yes, the D90 has better Photographic Dynamic Range than the D80 or even the D300.

I usually read this chart across.
So, in your case, locate the point on the D80 at at the highest ISO that gives you acceptable results.
Then go straight to the right and see where that falls on the D90 line.
That tells you the D90 ISO that will give you the same image quality.
For example, ISO 400 on the D80 and ISO 1600 on the D90 are both about 6EV Photographic Dynamic Range.


Bill

Visit me at My site

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

    
lofling Registered since 19th Jun 2008Tue 21-Oct-08 07:58 PM
1464 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#20. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 1


SE
          

>Second, would I be correct to also conclude that this translates to
>lower noise levels at all ISO's (again, assuming all else to
>be equal)?

Is this really correct, that dynamic range equals noise levels? I didn't think it was.

Anyway, thanks for posting your interesting results.

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

RichBeau Basic MemberMon 20-Oct-08 11:32 PM
179 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#2. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 0
Mon 20-Oct-08 11:39 PM by RichBeau

Bolton, US
          

Wow! It compares favorably with a D3. Now all my D300 carrying friends will be jealous! :-D

--Rich
In the Viewfinder

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

    
Aqualung Silver Member Awarded for his technical proficiency and numerous positive critiques over several years, most notably in the Sports forum Charter MemberTue 21-Oct-08 12:00 AM
6140 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#3. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 2
Tue 21-Oct-08 12:01 AM by Aqualung

near Boston, US
          

hey Rich, wanna trade?

Interesting findings...same sensor (D300 & D90) isn't it?

Chris
=====
D300/D3s & more glass than I dare tell the wife


Olympus OM-D EM-1, Olympus 12-40ƒ2.i, Panasonic Leica 25mmƒ1.4


Visit my Nikonians gallery.

Visit my Nikonians gallery.

Visit my Nikonians gallery.

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

        
bclaff Silver Member Awarded for multiple contributions for the Resources Nikonian since 26th Oct 2004Tue 21-Oct-08 12:05 AM
9681 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#4. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 3


Vancouver (WA USA not Canada), US
          

Chris,

same sensor (D300 & D90) isn't it?

No, I think similar technology but not the same sensor.
(I never thought so because of the D90 video capability.)


Bill

Visit me at My site

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

            
jaysd200 Registered since 03rd May 2007Tue 21-Oct-08 03:55 AM
149 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#6. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 4


yonkers, US
          

its is the same sensor, but it has a diffrent way of processing the image

Thanks
jay
kajphotos1.com
kajphotos@verizon.net

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

                
bclaff Silver Member Awarded for multiple contributions for the Resources Nikonian since 26th Oct 2004Tue 21-Oct-08 04:18 AM
9681 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#7. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 6


Vancouver (WA USA not Canada), US
          

Jay,

Not that it really matters since the overall performance of the camera is what counts, but...

Another hint that they are different is that the Color Filter Array (CFA) order is different.
(You can get this from the metadata.)
The D300 is RG;GB
The D90 is GR;BG

Of course it would be interesting to see hard evidence either way but I haven't seen any Nikon DSLR chip specs since the D70.


Bill

Visit me at My site

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

                    
jon_b Registered since 14th Jul 2008Tue 21-Oct-08 08:36 AM
268 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#8. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 7


GB
          

Bill

Thanks for that, very interesting. I’m a generally lazy person, who’s also not very good at RAW processing. As a result I tend to shoot jpg, do you have any observations of how ADR performs when compared to the results you can obtain with RAW processing for maximising range?

Thanks
Jon

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

                        
bclaff Silver Member Awarded for multiple contributions for the Resources Nikonian since 26th Oct 2004Tue 21-Oct-08 12:22 PM
9681 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#10. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 8


Vancouver (WA USA not Canada), US
          

Jon,

do you have any observations of how ADR performs

No. These studies are only on the raw underlying capability of the sensors.
(By ADR I assume you mean ADL, Active D-Lighting)


Bill

Visit me at My site

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

Tony_Jeffree Registered since 13th Oct 2004Tue 21-Oct-08 09:24 AM
2016 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#9. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 0
Tue 21-Oct-08 09:27 AM by Tony_Jeffree

Manchester, GB
          

Bill -

Thanks - that is indeed a surprising result.

An interesting feature of the graph is that it illustrates very well why it is that the D90's "normal" ISO range starts at 200 rather than 100 (although you can set it to "L 1" which is ISO 100) - below 200 there isn't any significant increase in PDR, so there's very little point in setting it lower than 200.

Another interesting feature is that there seems to be only a very marginal difference in performance between 12-bit and 14-bit, so the lack of 14-bit on the D90 is no great loss.

Regards,
Tony

My Nikonians Gallery

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

    
bclaff Silver Member Awarded for multiple contributions for the Resources Nikonian since 26th Oct 2004Tue 21-Oct-08 12:28 PM
9681 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#11. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 9


Vancouver (WA USA not Canada), US
          

Tony,

below 200 there isn't any significant increase in PDR, so there's very little point in setting it lower than 200.

I disagree with your reading of the data.
It's clearly best to shoot at ISO 100 (Lo 1.0) if you have enough light.
FWIW, it's ISO 100 is 1/6EV better PDR than ISO 200 for the D90 (9.25 vs 9.09).

only a very marginal difference in performance between 12-bit and 14-bit, so the lack of 14-bit on the D90 is no great loss.

There is, in fact, no difference in dynamic range between 12-bit and 14-bit.
The slight differences you see are indicative of measurement variation.


Bill

Visit me at My site

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

        
Tony_Jeffree Registered since 13th Oct 2004Tue 21-Oct-08 02:33 PM
2016 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#12. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 11
Tue 21-Oct-08 03:45 PM by Tony_Jeffree

Manchester, GB
          

>Tony,
>
>below 200 there isn't any significant
>increase in PDR, so there's very little point in setting it
>lower than 200.

>
>I disagree with your reading of the data.
>It's clearly best to shoot at ISO 100 (Lo 1.0) if you have
>enough light.
>FWIW, it's ISO 100 is 1/6EV better PDR than ISO 200 for the
>D90 (9.25 vs 9.09).

Bill -

OK - you get 1/6th of an EV advantage, but that is significantly less than you get when changing from 400-200, 800-400,...etc. which are all approx. 1EV steps in PDR.

I doubt if most of us would perceive the difference between ISO 100 and ISO 200 in practice, whereas we might notice a 1EV change in PDR.

Regards,
Tony

My Nikonians Gallery

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

            
bclaff Silver Member Awarded for multiple contributions for the Resources Nikonian since 26th Oct 2004Tue 21-Oct-08 04:09 PM
9681 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#14. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 12


Vancouver (WA USA not Canada), US
          

Tony,

Yes. It's a "slippery slope" deciding what amount is "perceptible".

In any case, there's no reason not to use ISO 100 if there is sufficient light; and you pick up that extra 1/6EV.

Regards,
Bill

Visit me at My site

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

                
Tony_Jeffree Registered since 13th Oct 2004Tue 21-Oct-08 04:22 PM
2016 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#15. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 14


Manchester, GB
          

Bill -

>Yes. It's a "slippery slope" deciding what amount is
>"perceptible".

That is certainly true. However, given that the camera can only operate in 1/3-stop increments of aperture/shutter speed, with a 1/6th EV difference in PDR you are down in the noise (pun intended!) when it comes to evaluating whether any difference you see is because of the 1/6th EV difference in PDR or the +- 1/6th stop of exposure error.

>In any case, there's no reason not to use ISO 100 if there is
>sufficient light; and you pick up that extra 1/6EV.

That is true.

Regards,
Tony

My Nikonians Gallery

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

MstrBones Silver Member Nikonian since 06th Dec 2005Tue 21-Oct-08 03:30 PM
8238 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#13. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 0


AW
          

Bill,

Your results seem to parallel the Imaging Resource test results, except the D700 came in just slightly ahead of the D90. The D300, against other cameras as well as Nikon's latest, came in a distant 9th.

Results here...

http://www.imaging-resource.com/PRODS/D90/D90IMATEST.HTM

""

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

    
bclaff Silver Member Awarded for multiple contributions for the Resources Nikonian since 26th Oct 2004Tue 21-Oct-08 04:24 PM
9681 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#16. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 13


Vancouver (WA USA not Canada), US
          

David,

I have a great deal of respect for Imatest and those are interesting results (which I have seen before).
However, I don't think anyone else is taking the Circle Of Confusion (COC) into account in their testing; and I feel strongly that my approach is "correct" for comparing camera performance.
I also think, that for the analysis I care about; analysis must be performed on the raw data, not JPGs.
(I do think there is value in testing "out of the camera" JPG performance. It's just not what my PDR measures.)

In your link, the reviewer expresses surprise at some of results in the two paragraphs below the "Dynamic Range vs Image Quality" table.
IMO, these musing on non-intuitive results stem from not taking COC into consideration.


Bill

Visit me at My site

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

        
Tony_Jeffree Registered since 13th Oct 2004Tue 21-Oct-08 04:29 PM
2016 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#17. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 16


Manchester, GB
          

>IMO, these musing on non-intuitive results stem from not
>taking COC into consideration.

You might even say that their results are COC-ked up

(sorry, couldn't resist...)

Regards,
Tony

My Nikonians Gallery

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

        
MstrBones Silver Member Nikonian since 06th Dec 2005Tue 21-Oct-08 05:27 PM
8238 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#18. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 16


AW
          

Bill,

If you read closely, Imaging Resource does both jpegs and RAW. The jpeg analysis is just that - for the people that are not going to shoot RAW.

More info, for those interested, here on how Imatest determines DR.

http://www.imatest.com/docs/dynamic.html

""

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

            
bclaff Silver Member Awarded for multiple contributions for the Resources Nikonian since 26th Oct 2004Tue 21-Oct-08 06:14 PM
9681 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#19. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 18


Vancouver (WA USA not Canada), US
          

David,

If you read closely, Imaging Resource does both jpegs and RAW.

If you read closely, you'll notice that they run their raw files through Adobe Camera Raw.
This is fundamentally different from analyzing the raw linear data.


Bill

Visit me at My site

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

                
MstrBones Silver Member Nikonian since 06th Dec 2005Tue 21-Oct-08 09:46 PM
8238 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#21. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 19


AW
          

>If you read closely, you'll notice that they run their raw files through Adobe Camera Raw.

Pretty standard practice, I believe DP Review does the same thing.

Bill, I was only making the point that they did not only evaluate jpegs, which is what you said in your post. In fact, I believe they make the comparison to show folks how much DR gets tossed by in-camera jpeg engines vs. a RAW file, regardless of who made the camera under test.

""

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

                    
bclaff Silver Member Awarded for multiple contributions for the Resources Nikonian since 26th Oct 2004Wed 22-Oct-08 12:48 AM
9681 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#22. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 21


Vancouver (WA USA not Canada), US
          

David,

I believe they make the comparison to show folks how much DR gets tossed by in-camera jpeg engines vs. a RAW file

Yes, but my point is that they don't measure the full raw potential because they don't analyze the linear data.
The essentially analyze a (lightly) post processed raw image.

BTW, this is an observation, not a complaint. I understand why they have taken that approach.

Regards,
Bill

Visit me at My site

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

                    
ChrisLilley Registered since 14th Jul 2007Tue 25-Nov-08 07:41 PM
506 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#37. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 21


GB
          

>>If you read closely, you'll notice that they run their
>raw files through Adobe Camera Raw.
>
>Pretty standard practice, I believe DP Review does the same
>thing.

Yes, and that is one reason why these results are flawed and of little interest to those of us who shoot RAW.

>Bill, I was only making the point that they did not only
>evaluate jpegs, which is what you said in your post.

They are testing JPEGs - either those produced by the camera, or those produced b a third party program which is known to have incompatibilities with Nikon RAW data. Either way, its testing JPEGs.

> In fact,I believe they make the comparison to show folks how much DR
>gets tossed by in-camera jpeg engines vs. a RAW file,
>regardless of who made the camera under test.

Its interesting to compare different JPEG production methods, true.

Its also interesting to compare the RAW data that cameras produce; which the new DxOMark does, and which Bill does also. This involves reading the RAW data and analysing it directly. This is fundamentally different to converting the RAW data to JPEG and then analysing that. (Its also, by the way, different even to converting the RAW data to a 16 bt TIFF or PNG, which misses out the JPEG lossiness but still involve white balancing and RAW conversion.

Shooting RAW (and archiving the unedited RAW files) offers the hope of better conversion in the future. We are already seeing this, for example RAW converters that perform noise reduction before de-Bayering.

--
Camera <ˈkæ mə rə>, n. Device for taking pictures in bright light.
http://www.flickr.com/photos/nantonos

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

C2020 Registered since 20th May 2006Mon 27-Oct-08 03:01 PM
267 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#23. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 0


US
          

Bill,
Thank you for the data, I don't understand it completely but I am happy to see my D90 does successfully address one of the short comings of my old D80.

I'm an optometrist, in optics an astigmatic lens corrects astigmatic refractive error at the "circle of least confusion"- a physical point in space where the perpendicular lines of focus form the sharpest focus. Is the 'circle of confusion' which you discuss above similar to the circle of least confusion or does it have more to do with the focal range of visible light--380-700nm?
Bob
D90, Nikon 80-200mm f/2.8 D, Sigma 18-50mm f/2.8, Nikon 105mm f/2.8 micro, etc...

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

    
bclaff Silver Member Awarded for multiple contributions for the Resources Nikonian since 26th Oct 2004Mon 27-Oct-08 08:06 PM
9681 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#24. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 23


Vancouver (WA USA not Canada), US
          

Bob,

Regarding photographic Circle Of Confusion (COC), we're really talking about visual acuity.
Try reading "Circle of Confusion" under "Backgrounders" at my site (URL in signature).

Regards,
Bill

FWIW (minutia), the perpendicular lines of focus don't really form a point in space; they form an Airy disc whose size depends on the aperture.

Visit me at My site

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

purdyd Registered since 12th Jul 2008Thu 30-Oct-08 12:15 AM
5 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#25. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 0


US
          

>The D90 has better Photographic Dynamic Range than the D300 at
>every ISO.
>And the Photographic Dynamic Range even exceeds the D3 and
>D700 at ISO 100 (but not above ISO 200).

Bill,

If the D90 is like the D300, i suspect the real base iso is 160, not 100 or 200

Also, at the raw level, from the samples i could compare from imaging resource, the D300 is showing detail that the D90 lacks

thus the D90 appears to be sacrificing some detail for decreased noise and thus in your test will show an increased dynamic range

http://farm4.static.flickr.com/3268/2909997409_8dc6d6c1a7_b.jpg



  

Alert Printer-friendly copy | Reply | Reply with quote | Top

    
bclaff Silver Member Awarded for multiple contributions for the Resources Nikonian since 26th Oct 2004Thu 30-Oct-08 01:11 AM
9681 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#26. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 25


Vancouver (WA USA not Canada), US
          

David,

If the D90 is like the D300, i suspect the real base iso is 160, not 100 or 200

The "native" ISO is clearly between ISO 100 and ISO 200 but I don't have enough of the right D90 data to calculate the value.

My guess is that it is much closer to ISO 200 than for the D300.

These are (IMO) clearly different sensors (but related technology).

the D90 appears to be sacrificing some detail for decreased noise

I don't test sharpness but have seen no indication of this myself (at a raw level).
Once difference could be a different Optical Low Pass Filter (OLPF); that would affect sharpness.


Bill

Visit me at My site

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

        
purdyd Registered since 12th Jul 2008Thu 30-Oct-08 02:43 AM
5 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#27. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 26
Thu 30-Oct-08 03:25 AM by purdyd

US
          

this the view of the raw data in a program called raw analyze and a dark patch has been boosted 5 stops - you can see there is more detail in the D300 picture in the middle

http://farm4.static.flickr.com/3268/2909997409_8dc6d6c1a7_b.jpg

those shots were from the imaging resource raw files

this would also agree with the dpreview review of the D90 where they note it (D90) captures less detail than the D300 - even in raw

it could be optical low pass filter or it could be a different on sensor noise reduction algorithm

Sony clearly shows noise reduction on a similar sensor

http://www.sony.net/Products/SC-HP/cx_news/vol50/pdf/imx021.pdf

whatever the cause - i think it is difficult to compare noise without also comparing the amount of detail resolved

we have clearly seen this in jpegs at higher iso levels and it appears to me with cmos sensors that this is also now pertinent at the raw level

i mention the iso 160 as the base iso because if it is like the D300, and i think it is, there is no difference in noise from iso100-iso160 - and iso100 and iso125 are essentially iso160 with +1/3 and +2/3 exposure compensation

regards,

David







  

Alert Printer-friendly copy | Reply | Reply with quote | Top

stevesummerford Registered since 26th Oct 2008Fri 31-Oct-08 10:45 PM
5 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#28. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 0


US
          

Hello, At the risk of getting slightly off topic...I too just like Graceland, have been considering a camera upgrade from my D80. So my question here would be... how do these results for the D90 figure in to a choice of upgrade between a D90 and a D300? If the dynamic range is better on the D90, but the D300 has greater detail, is it better to spend the $500 difference for a better lens? Thanks, my primary use for the upgraded camera would be for wedding photography.

Visit my Nikonians gallery.

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

    
bclaff Silver Member Awarded for multiple contributions for the Resources Nikonian since 26th Oct 2004Fri 31-Oct-08 11:27 PM
9681 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#29. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 28


Vancouver (WA USA not Canada), US
          

Steve,

I can't speak to the sharpness issue except to say that there are many factors that can affect sharpness in test images that have nothing to do with the sensor itself, so I personally am not convinced that sensor sharpness is (that) different between the D300 and the D90.

As for photographic dynamic range, the results speak for themselves.

However, the D300 has features that the D90 does not have or that are better on the D300 than the D90.
So photographic dynamic range is simply one of several factors to take into consideration.

I do think this is a little "off topic" (OT).
If anyone wants to continue the discussion of D90 versus D300 I suggest posting a new thread.


Bill

Visit me at My site

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

        
stevesummerford Registered since 26th Oct 2008Sat 01-Nov-08 12:22 AM
5 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#30. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 29


US
          

Thanks Bill! This information is useful. I'm sure from reading some of the other threads I'll find the information I need to make a decision.
Thanks Again.

Steve

Visit my Nikonians gallery.

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

        
purdyd Registered since 12th Jul 2008Sat 01-Nov-08 01:27 AM
5 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#31. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 29


US
          


>As for photographic dynamic range, the results speak for
>themselves.

Bill,

I am having a hard time believing that the D90 beats the D3 in noise @ iso200, which is basically what your photographic dynamic range chart shows, unless there is some additional noise reduction going on

the change in the slope of the curve is also somewhat suspicious

since your test is a dark frame test - i have to conclude it is the processing of the data that is different

i don't believe Nikon/Sony made a sudden magical breakthrough in sensor technology - i think we would have heard about it

also, looking at the masked sensor data on the right at iso160/200 it appears that the sensors are essentially the same at the light gathering level

Regards,

David





  

Alert Printer-friendly copy | Reply | Reply with quote | Top

            
bclaff Silver Member Awarded for multiple contributions for the Resources Nikonian since 26th Oct 2004Sat 01-Nov-08 12:22 PM
9681 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#32. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 31


Vancouver (WA USA not Canada), US
          

David,

I was surprised too, hence the title of the post; but I have no reason to doubt the results.
(I even gathered extra sets of data before presenting them.)

The D90 curve has essentially the same shape as the D300, it's just higher across the board.
If anything the datapoint at ISO 400 for the D90 looks a tiny bit low.

I have already demonstrated that the D200, D300, and D3 (the only cameras for which I have sufficient data) do noise reduction at the raw data level for long exposures (D200 >1 1s, D300/D3 >= 1/4s)

The images used to determine Photographic Dynamic Range are taken at 1/250s and should have no noise reduction unless the D90 is fundamentally different.
(I'm waiting to get some additional D90 data to know for sure.)

The improved noise for the D90 could come from a combination of a slightly reduced readout rate and a slightly better amplifier.
Without the actual specs and doing "black box" experiments; it's impossible to know.


Bill

Visit me at My site

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

                
purdyd Registered since 12th Jul 2008Sat 01-Nov-08 07:14 PM
5 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#33. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 32


US
          

Bill,

I don't doubt your results at all. I already spent some time looking at the raw files in a discussion on another forum.

However, it is my opinion, there is a loss of detail in the D90 vice the D300 in raw, and the D90 has less noise. Pick your poison.

i only have one more data point - on the right side of the sensor in the raw data there is a column of 32 sensors which according to Iliah Borg are masked (and also dropped by dcraw i might add) and if you look at them you can get the true 'read noise'- that might be true - and Nikon conveniently added an offset so you can see the curve

http://farm4.static.flickr.com/3008/2580463937_4836fd7dea_o.jpg

then i plotted the standard deviation of the green channel versus iso - excuse me if it is a little ragged - used a random subset to generate the curve

http://farm4.static.flickr.com/3241/2852108996_18093db635_o.jpg

this would suggest this is the raw A2D converted masked sensor output and i would theorize that iso160 to iso1600 is done with analog gain and ISO2000 and above has additional digital gain

so i thought - lets see what the D90 looks like - of course it is compressed 12 bit but it is very interesting - because at ISO100 and 200 it looks the same as the D300 but from then on - very different

http://farm4.static.flickr.com/3175/2852109114_dc97cebef4_o.jpg

it would appear that the D90 makes more use of digital gain vice the d300

Bill, I agree with your results, there is less noise in the D90 raw files but it appears the underlying a2d conversion and base read noise is the same

how that reduction in noise in the actual raw outpout is achieved, i can't say - but from what i can see - it doesn't appear to be in the analog section

and as we can see from the IMX021 block diagram (the sibling of the D90 and D300 sensor) there is some sort of digital noise reduction on board the chip

http://farm4.static.flickr.com/3209/2921749684_fb8cb87fb1_b.jpg

so both the D90 and D300 have this feature - probably even the D3 and Canon CMOS sensors

so while immensely respect your testing and results (i love the SB800 output power versus shutter speed test) - the basic premise is that you are getting for the most part really raw sensor data

unfortunately, i don't think that is the case anymore

i believe Nikon tweaked the D90 to give better noise performance at the expense of detail- i have noticed it and as I stated - dpreview noted it

incidentally it looks like Canon might have done the same thing on their 50D

is it a good or bad thing? i don't think it is either - it just is - the D90 gives some great pictures and ISO3200 is particularly impressive

highest regards,

David





  

Alert Printer-friendly copy | Reply | Reply with quote | Top

                    
bclaff Silver Member Awarded for multiple contributions for the Resources Nikonian since 26th Oct 2004Sat 01-Nov-08 07:31 PM
9681 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#34. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 33


Vancouver (WA USA not Canada), US
          

David,

I'm familiar with that noise data and have been using it long before Iliah "announced" it at dpreview.
You'll see it in my "Sensor Characteristics" table under "Investigation" at my site in the column with the footnote "Nikon proprietary".
These are values read from the photosites under the "optical black" on the sensor.

As for sharpness, it's simply something I don't measure in some objective way.
It's entirely likely that the OLPF is stronger as opposed to sharpness being lost to some sort of noise reduction.

Regards,
Bill

Visit me at My site

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

                    
bclaff Silver Member Awarded for multiple contributions for the Resources Nikonian since 26th Oct 2004Sat 01-Nov-08 11:39 PM
9681 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#35. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 33


Vancouver (WA USA not Canada), US
          

David,

I have demonstrated (to my own satisfaction!) that the D90 does no form of noise reduction that would destroy detail at exposures faster than 1s.
See D90 Does Noise Reduction on NEFs at Longer Exposures for the details.
(If you don't understand FFTs or the implications, you'll have to trust me!)

So, if detail is lost then I'm leaning heavily toward the OLPF (anti-aliasing).

Regards,
Bill

Visit me at My site

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

                        
kjyuan Registered since 24th Nov 2008Mon 24-Nov-08 08:09 AM
2 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#36. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 35


US
          

This is very useful information thank you bill

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

        
rjackson43 Registered since 05th Feb 2009Tue 10-Feb-09 08:40 PM
2 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#54. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 29


Ballston Lake, US
          

Bill,

Thanks for this awesome persistant thread! I am wondering if anyone did start the new thread re: D90 vs. D300? I am still contemplating if/when I upgrade from my trusty D70 which way would be better? I primarily take sports and nature shots, motorized and athletic at the collegiate and scholastic levels. I do find that I am wishing that I could utilize higher ISO's without "noise". I also preferred using Velvia and Reale for nature so lower than 200 also appeals to my film roots.

TIA

Rod

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

            
bclaff Silver Member Awarded for multiple contributions for the Resources Nikonian since 26th Oct 2004Tue 10-Feb-09 08:59 PM
9681 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#55. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 54


Vancouver (WA USA not Canada), US
          

Rod,

It's clear that the D90 has an edge over the D300 regarding dynamic range and noise.
But it's not at all clear that this (slight) advantage outweighs the strengths of the D300.
I have a D300 and don't envy my friend with his D90.
My D300 has better AF and other features that make it better suited to my purposes which include wildlife photography.
I suspect the same would apply to sports.
On the other hand, the D90 is very capable and less expensive.
If getting a D90 means being able to get better lens(es) then that makes it a tougher call.


Bill

Visit me at My site

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

                
rjackson43 Registered since 05th Feb 2009Tue 10-Feb-09 10:10 PM
2 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#56. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 55


Ballston Lake, US
          

Bill,

Thanks for your response, I would agree, I am using the old "one-touch" 80-200 f2.8 as my primary for most sports, would possibly be considering a used 80-400VR and a used D300 vs new D90 and the used 80-400 if I can support both purchases at the same time. The lens will be secondary purchase either way. I overlap with the 24-85mm, 18-35mm and the real dog in my bag is the 70-300G early version (can we say plasticy and loose?). I sill love the heavy tanklike 80-200 even if I would have preferred the "two-touch". Our subjects/styles wouuld definitely seem to be similar, and I am thinking that the D300's focusing could be the deal maker. Thoughts?

Rod

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

                    
bclaff Silver Member Awarded for multiple contributions for the Resources Nikonian since 26th Oct 2004Tue 10-Feb-09 11:10 PM
9681 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#57. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 56


Vancouver (WA USA not Canada), US
          

Rod,

I haven't used a D90 enough to be certain but on paper the D300 should have a real edge in terms of AF.
As I said, I'm glad I have the D300 and don't regret not having the D90.
Check the Galleries at my site for some D300 examples.
(The "All My Images" Gallery has "Exif" information and is in reverse chronological order.)


Bill

Visit me at My site

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

ChrisLilley Registered since 14th Jul 2007Tue 25-Nov-08 07:45 PM
506 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#38. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 0


GB
          

Bill, do you have (and are willing to share) the numerical data from which this graph was plotted? I could estimate it from the graph but it would be easier and more convenient to work from tabular data.

I'm interested in replotting it, with the x-axis being the actual measured ISO (DxOMark makes this data available) rather than the nominal ISO that the camera reports. i see that some cameras have a substantially lower effective ISO than the reported one, and i would be interested to examine a graph that plots these data this way.

--
Camera <ˈkæ mə rə>, n. Device for taking pictures in bright light.
http://www.flickr.com/photos/nantonos

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

    
bclaff Silver Member Awarded for multiple contributions for the Resources Nikonian since 26th Oct 2004Tue 25-Nov-08 09:41 PM
9681 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#39. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 38


Vancouver (WA USA not Canada), US
          

Chris,

Send me e-mail and I will reply with an Excel sheet.
However, I feel strongly that your intended re-use is incorrect.

The intention should be to do comparisons at the same exposure (amount of light gathered).
Images from two cameras taken at the same f-stop, shutter, and (marked) ISO should be collecting identical amounts of light.
Whether "marked" ISO matches "real" ISO is not relevant to this comparison.

Also, remember, to take full advantage of the dynamic range for any camera at any ISO requires Exposing To The Right (ETTR).
And ETTR will eliminate any shift due to any ISO variation.

Regards,
Bill

Visit me at My site

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

        
ChrisLilley Registered since 14th Jul 2007Wed 26-Nov-08 12:42 PM
506 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#40. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 39


GB
          

>Chris,
>
>Send me e-mail and I will reply with an Excel sheet.

Thanks, appreciated.

>However, I feel strongly that your intended re-use is
>incorrect.

In that case, your willingness to share the data is even more appreciated.

>The intention should be to do comparisons at the same exposure
>(amount of light gathered).

I agree.

>Images from two cameras taken at the same f-stop, shutter, and
>(marked) ISO should be collecting identical amounts of light.

They *should*, yes. The issue is that they are not. Since people mostly use the internal metering of the camera, rather than an external meter, this effect is hidden.

>Whether "marked" ISO matches "real" ISO is
>not relevant to this comparison.

I disagree. Only by plotting the actual ISO, rather than one rounded off to a convenient number, can accurate conclusions be drawn.

Suppose I am a camera manufacturer and I supply you two cameras for testing. They are identical, except that one falsely reports the ISO to be a whole stop slower than it actually is. (Suppose too that the meter compensates for this). ISO 400 is actually marked as 200 and so on. With that big a difference you would doubtless note that something is amiss; with the two cameras in hand at the same time, you wold notice that the shutter speeds or apertures suggested by the in-camera metering are different. On the other hand, a tester might well conclude that the second camera has much better noise results at ISO 800 and 1600. Because the results are actually those for 400 and 800 ...

However, customers prefer familiar and round numbers. We don't see lenses marketed as f/2.5 or f/1.9 any more. They round to industry standard numbers.

Similarly shutter speeds are of course on a series where each is exactly half the speed of the preceding shutter speed; but these are again rounded off so instead of

1/2 1/4 1/8 1/16 1/32 1/64 1/128 1/256 1/512

we have

1/2 1/4 1/8 1/15 1/30 1/60 1/125 1/250 1/500

Getting back to ISO, DxOMark reports that at a nominal ISO 800, for example, the D200 is at 759, the D40 is actually at 705 while the D90 is in fact at 589 and the D300 is at 571! This is not a small error, particularly for the D90 and D300.

At the same aperture and shutter speed, the less sensitive sensor is collecting less light.

>Also, remember, to take full advantage of the dynamic range
>for any camera at any ISO requires Exposing To The Right
>(ETTR).
>And ETTR will eliminate any shift due to any ISO variation.

I certainly agree about the need for ETTR, and wish that cameras gave actual per-channel raw histograms (rather than histograms derived from a white-balanced image) so that the amount of higlight clipping could be more easily determined.

--
Camera <ˈkæ mə rə>, n. Device for taking pictures in bright light.
http://www.flickr.com/photos/nantonos

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

            
bclaff Silver Member Awarded for multiple contributions for the Resources Nikonian since 26th Oct 2004Wed 26-Nov-08 02:51 PM
9681 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#41. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 40


Vancouver (WA USA not Canada), US
          

Chris,

you wold notice that the shutter speeds or apertures suggested by the in-camera metering are different.

No! This is the flaw to your reasoning.

Two different cameras, set to the same ISO, and exposed to the same amount of light, will give the same aperture/shutter speed values.

Assume that amount of light is a uniformly illuminated frame.
This will produce a raw histogram with a very sharp peak.
The position of that peak along the x-axis in the raw data will often differ from camera to camera even though they have been exposed to the same amount of light.

One way (there are more than one) of computing the "true" ISO of a camera is to compare where the peak falls with some fixed value such as 18% of full scale.
In your (extreme) example, a camera "marked" at ISO 200 but actually ISO 400; the peak might fall at 36% as opposed to 18%.

So, "marked" versus "true" ISO doesn't change the amount of light gathered, it affects where the peak falls on the x-axis of the raw histogram.
At most this means that for the two cameras you may need different amounts of Exposure Compensation to Expose To The Right (ETTR).

Regards,
Bill

Visit me at My site

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

                
ChrisLilley Registered since 14th Jul 2007Sun 30-Nov-08 02:58 PM
506 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#42. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 41
Sun 30-Nov-08 02:59 PM by ChrisLilley

GB
          

Bill,

But simply moving the position of the peak is what changing ISO *does*, surely. By the way, my example was the opposite of what I wanted to propose: it should have been ISO 200 actually marked as 400. So the peak would fall at 9% (if, as you say, the metering is correct for the marked ISO rather than the correct, calibrated or measured ISO). But the noise for this 'fake 400' would be quite good, and exactly like the noise for ISO 200 in the other camera. That was my point, really; by reporting an ISO value which is higher than the measured value, the cameras which do so seem to have a better noise performance at high ISO than they in fact really have.

Since you assert that my reasoning is incorrect, I have been reading up on the subject. I'm trying to reach a reasoned conclusion on whether you are correct, or whether the folks that use true measured ISO values are correct.

This posting (and rest of the thread) supports correction for true ISO
http://forums.dpreview.com/forums/read.asp?forum=1039&message=30074241

DxOMark plots against true ISO:
http://www.dxomark.com/index.php/eng/DxOMark-Sensor/Data-normalization

One of the most useful explanations I found was this one (I am still reading it):
http://theory.uchicago.edu/~ejm/pix/20d/tests/noise/index.html
in particular
http://theory.uchicago.edu/~ejm/pix/20d/tests/noise/noise-p2.html#read_vs_iso
(which cites your data)
(incidentally, the Canon 1D3 results are just *bizarre*)

The image combination technique described here is convincing (and shows a real-world, it-makes-the-image-better result of the theoretical analysis):
http://theory.uchicago.edu/~ejm/pix/20d/tests/noise/noise-p3a.html

As I said, still reading and thinking.

--
Camera <ˈkæ mə rə>, n. Device for taking pictures in bright light.
http://www.flickr.com/photos/nantonos

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

                    
bclaff Silver Member Awarded for multiple contributions for the Resources Nikonian since 26th Oct 2004Sun 30-Nov-08 06:02 PM
9681 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#43. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 42


Vancouver (WA USA not Canada), US
          

Chris,

I think it's great that you're reading up on the subject and still thinking.

Regarding your reading material, I would put the most stock in Emil Martinec's work.
It's no surprise that he cites some of my data as we have often exchanged e-mails. Generally he and I agree.
(I think he owns Canon and relies on others for Nikon data.)

The crux of this confusion, which is widespread, is that we carelessly use the term "ISO" in two (or more!) ways.

The ISO that I use on the x-axis of my Photographic Dynamic Range (PDR) Chart is the "marked" ISO; perhaps better called the "metering" ISO.
This value controls the amount of light, per unit area, per unit time, that reaches the sensor.
If we assume that metering is correct (and I do), then, under identical lighting conditions; all cameras will compute the same exposure (aperture and shutter) at the same "marked/metering" ISO.
So, the question becomes; exposed to the same amount of light, per unit area, per unit time; how much PDR is captured by the sensor.

The preceding paragraph is really the complete reasoning at to why "marked/metering" ISO is the only appropriate choice for the PDR Chart.

But, let's go on... The remainder of this post is not for the faint of heart

We also use the term ISO to characterize the sensitivity of the sensor; we have been calling this "true" ISO.
It is an attempt to characterize the "ISO equivalent" relative to film; perhaps better called "(film) equivalent" ISO.
Along the processing chain from photodiode (photons -> electrons) to digital value (Analog to Digital Units, ADUs) is a Programmable Gain Amplifier (PGA).
Amplifier gain should be reported in units of ADUs/electron but is often reported in the inverse units of electrons/ADU.
For any particular sensor there is a linear relationship between the gain (in ADUs/electron) and ISO equivalent.
The lower the gain (in ADUs/electron), the lower the ISO equivalent.
However, there is a minimum gain (in ADUs/electron) at which point the full range of the ADU will not be used (because the photocell can only hold so many electrons, the Full Well Capacity (FWC)).

For simplicity let's say a sensor with a FWC of 20,480 electrons and a minimum gain of .2 ADUs/electron (5 electrons/ADU); this produces ADU values from 0 to 4096.
The "64,000 dollar question" is: what is the ISO equivalent of .2 ADUs/electron ???
There is more than one answer, even consulting ISO standards; but let's proceed.
One way to compute the "(film) equivalent" ISO is to assume that even illumination gathered at a properly marked "metering" ISO will have a peak that falls at 18% of the full ADU scale.
(But you could argue for values other than 18%, and there are other methods.)
For this example, let's say .2 ADUs/electron is "(film) equivalent" ISO 200 and .4 ADUs/electron is "(film) equivalent" ISO 400.

Now, gathering light at a "marked/metered" ISO of 400 has (nearly) identical noise and dynamic range regardless of whether the gain used is "(film) equivalent" ISO 200 or "(film) equivalent" ISO 400.
The noise in the signal (photon noise) is identical because the same amount of light per unit area is gathered.
The noise in the photosite (reset, read, dark current) is identical because this is before the PGA.
The gain at the PGA amplifies both the signal and the noise so the Signal to Noise Ratio (SNR) is unaffected by the PGA.
Except that the PGA introduces a very small amount of new noise and that amount increases with gain (this is where the "nearly" comes from).

FWIW, if the intent is to measure the raw capabilities of a sensor then I would argue that all results really ought to be presented in terms of electrons; and gain rather than "(film) equivalent" ISO.

Regards,
Bill

Visit me at My site

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

                        
Sandor Registered since 12th Feb 2008Mon 19-Jan-09 07:20 AM
9 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#44. "ntxt"
In response to Reply # 43
Mon 19-Jan-09 07:22 AM by Sandor

NL
          

ntxt

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

Sandor Registered since 12th Feb 2008Mon 19-Jan-09 07:20 AM
9 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#45. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 0
Mon 19-Jan-09 07:23 AM by Sandor

NL
          

Hi all,
How does the D60 perform?
This is the only model missing in the graph.
I am on the point of buying my first DSLR and doubting between the D40/D60/D80/D90. On this aspect the D80 seems to be the loser (is/was my favourite) the D90 is the big winner (but most expensive of the four) D40 is better than D80, is the D60 better than the D40????

Greetings
Sandor

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

    
ChrisLilley Registered since 14th Jul 2007Mon 19-Jan-09 02:32 PM
506 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#46. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 45


GB
          

I would expect the D60 to have the same results as the D40x since they have the same 10MPx sensor and are pretty much the same camera with a couple of minor feature changes and a different model number to position that model in the range better (ie to be easier for consumers to understand).

--
Camera <ˈkæ mə rə>, n. Device for taking pictures in bright light.
http://www.flickr.com/photos/nantonos

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

        
arcusmay Registered since 13th Dec 2008Mon 19-Jan-09 10:15 PM
34 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#47. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 46


Williamsburg, US
          

WOW this subject has been staying put. Ok here is my deal. I was going to buy the D300 until one day I noticed some ISO comparison with the D90. The noise in the 300 was actually very much more abvious around 1400. The 90 held steady. A month or so ago I was on this link with a person who started it by say he borrowed his friends new 90 to compare to his 300. The resulsts where the same and he even has picturse comparisons on that thread (its somewhere on this site). I read on this thread some where wondering if the sensor is different and some say yes and some say no. I actually have not investigated this that far. I'll use the laymen's thought on this. The 300 is about 2 years old (it is a computer so that increases the age to 20 yrs old technology...im being facetious) On the other hand the 90 was one month old (that would make its technology....1 year old....again im being facetious). So it makes sense that the guts of the 90 would be newer and better then the 300. I must have to say thought the 300 is an awsome camera with options the 90 does not have. I bet in a year there will be a 300x that will blow away the 90 and I bet 1.5 years after that happened the 90 will be updated to a 90x. And will have features equal the the 300 but better...............this is the game we play in the digital world guys...............overall one thing to keep in mind it should always be the photographer controlling the camera and not the camera controling the photographer...........heck some pros will detune their DX's and FX's to shooting 6-8mp's to capture more info per pixal. Which this info stuns me as to the 3x with 30 something MP..........I bet they could have kept MP's in the low 20's and still remained (in my opinion) the greatest Dslr camera under $10,000. Well these are my meak thoughts

Marcus

<--- My Son *Photography is a hobby and Photography is a way of life. It does not matter which you choose to be, just as long as you are enjoying it.* Please....enjoy it !!!

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

            
bclaff Silver Member Awarded for multiple contributions for the Resources Nikonian since 26th Oct 2004Fri 23-Jan-09 12:38 AM
9681 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#49. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 47


Vancouver (WA USA not Canada), US
          

Marcus,

I own a D300 and have no regrets relative to the D90; they are different cameras.
Speaking of different... they absolutely have different sensors despite having the same resolution.


Bill

Visit me at My site

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

    
bclaff Silver Member Awarded for multiple contributions for the Resources Nikonian since 26th Oct 2004Fri 23-Jan-09 12:36 AM
9681 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#48. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 45


Vancouver (WA USA not Canada), US
          

Sandor,

The D60 is one of the few model for which no one has every submitted data.
The test is quite easy, and gotten easier recently.
Perhaps I'll issue another appeal.

It is likely that performance will be similar to the D40x but you never know because there are electronics other than the phsyical sensor that affect the results.


Bill

Visit me at My site

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

        
Sandor Registered since 12th Feb 2008Tue 27-Jan-09 07:53 AM
9 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#52. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 48


NL
          


>It is likely that performance will be similar to the D40x but
>you never know because there are electronics other than the
>phsyical sensor that affect the results.
>
That's exactly how I thought about it. Hope to see some results in the future...

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

davidziff2 Silver Member Charter MemberSat 24-Jan-09 02:18 PM
19 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#50. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 0
Sat 24-Jan-09 02:21 PM by davidziff2


          

Dear Bill,

Thanks for the good work you're doing to inspect the capabilities of Nikon DSLRs. The graph you presented was an eye-opener.

I wonder if you have examined the camera ratings at Dxomark.com which include both the D700 and the D90.

Looking at the DXO lab evaluation you'll see that the dynamic range of the D700 is 12.2 compared to the higher rating of the D90 at 12.5 but that there's a significant gap with respect to the low-light ISO rating -- with the D700 at 2303 (the highest recorded of all cameras examined) and the D90 at a much lower 977.

My question is this: is your own graph of dynamic range at each ISO consistent with the DXO Lab analysis - and if so, how? I would very interested in your reply.

Best, David




  

Alert Printer-friendly copy | Reply | Reply with quote | Top

    
bclaff Silver Member Awarded for multiple contributions for the Resources Nikonian since 26th Oct 2004Sat 24-Jan-09 04:19 PM
9681 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#51. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 50


Vancouver (WA USA not Canada), US
          

David,

The curves for the D700 and D90 behave differently, especially at low ISO.
If you look at the chart in my original post, the "low light ISO" is approximately where each curve crosses the PDR value of 6.5

I use a different methodology and threshholds than DxO so our low ISO values are not in total agreement.
See Photographic Dynamic Range compared with DxOMark for some more details.


Bill

Visit me at My site

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

        
davidziff2 Silver Member Charter MemberTue 10-Feb-09 07:53 AM
19 posts Share on Facebook Share on Twitter Share on Linkedin    Click to send email to this author Click to send private message to this authorClick to view this author's profile
#53. "RE: D90 Photographic Dynamic Range - Surprising Result"
In response to Reply # 51



          

Bill, thanks for your reply. I didn't see it until today.

  

Alert Printer-friendly copy | Reply | Reply with quote | Top

Forums Lobby GET TO KNOW YOUR CAMERA & MASTER IT Nikon D90/D80/D70 (Public) topic #223238 Previous topic | Next topic


Take the Nikonians Tour and learn more about being a Nikonian Wiki /FAQ /Help Listen to our MP3 photography radio channels Find anything on Nikon and imaging technology - fast!

Copyright © Nikonians 2000, 2014
All Rights Reserved

Nikonians®, NikoScope® and NikoniansAcademy™ are trademarks owned by Nikonians.org.
Nikon®, Nikonos® and Nikkor® are registered trademarks of Nikon Corporation.