Hi,

I'm wondering about the effects of diffraction with the D7K. It is my understanding that as pixel density increases so does diffraction. Do you think this will be an issue with this camera?

Enjoy!
Randy

While theoretically that is correct I would think the average person would not really see a difference.

CambridgeinColour has a good tutorial on diffraction. In Part 2 if you scroll down there is a Diffraction Limit Aperture Calculator that will allow you to plug in the sensor size and pixel resolution which will allow you to compare the differences.

Pete

Visit my Nikonians gallery.

yes diffraction is going to come in a bit sooner
this is going to get the people that shoot landscapes and macro
as diffraction is probably going to start in at F11
but the extra MP makes it a bit easier to sharpen

--------------
friends don't let friends pixel peep

Here is a quote from Lloyd Chambers:

The new Nikon D7000 shows promise, but finding lenses that can deliver to a sensor with 4.7-micron photosites should prove an interesting challenge, certainly not something likely with most consumer zooms, which is what Nikon shows the camera with in its marketing; having 16 megapixels is a token specification if the lenses cannot deliver. The new 35/1.4G (below) might be just such at lens, at least stopped down to f/2.8. Worth understanding is that diffraction will limit performance to f/5.6 with per-pixel performance quickly degrading at f/8 and beyond.

http://diglloyd.com/diglloyd/

Tom
Bay Area Nikonian

http://www.tkphoto.me/

Interesting. Can someone point me to some real world photos online that clearly demonstrate diffraction of existing D-SLR's?

Since most pocket cameras must have photosites which are far smaller than 4.7-microns, and since they rarely shoot wider than f4 or f5.6, why isn't diffraction a widely seen problem? Or are we just not looking for it (on these cameras)?

While diffraction is a very real phenomenon, opinions about the effects on an image can vary widely. And subject matter can also affect how much diffraction will matter in an image.

For example landscape photographers will generally try to avoid diffraction, yet macro photographers will generally accept a certain amount of diffraction. Reason it is accepted in macro photography is that the added elements through a greater DOF outweigh the small amount of loss due to diffraction.

As I stated earlier, Cambridge in Colour has a good tutorial on diffraction. In Part 1 if you scroll down to ‘What it Looks Like’ they provide a sample where you can roll over the f-number to see what the image looks like with and without diffraction.

Also a Google of ‘diffraction sample images’ turned up this page at DPreview where someone put up examples. But if you notice all the samples are extreme crops of small sections of the capture.

So yes diffraction is real, and the smaller the pixel size the quicker the onset. How much that will affect your images is up to you.

Pete

Visit my Nikonians gallery.

Hi,

Thanks for your responses. I do a lot of landscape and macro photography, so this subject is important to me.

Enjoy!
Randy

Here is a thread demostrating just how badly diffraction destroys macro images. OK, it's not on a 16mp D7000 but at f/29 I think it's safe to say that it's at least as limiting.

_____
Brian... a bicoastal Nikonian and Team Member

My gallery is online. Comments and critique welcomed any time!

Brian,

Thanks for the link. I use f/16 quite often with my D300s and macro lens. I hadn't been going beyond that but after seeing the image in the link I'm going to do some tests at f/22 and beyond.

Enjoy!
Randy

I've found f/54 and f/64 kind of problematic - you can get those on the 85/f2.8 PC if you stop down all the way (f/45) and then focus in closely. But I think we can agree that f/64 on current cameras is kind of extreme. And on that particular lens, I can probably work around the need for f/45+ anyway, precisely because it's that (tilt) lens.

_____
Brian... a bicoastal Nikonian and Team Member

My gallery is online. Comments and critique welcomed any time!

Brian

Are you saying for F11 landscapes you do not see this as a concern?

Thanks

Jerry Jaynes
Great Smoky Mountains
of North Carolina

http://www.flickr.com/photos/by_jerry_jaynes/

No, I don't. I shoot landscapes at whatever aperture suits the photographic purpose, often including f/22. I'd use f/32 if my lenses had it, probably. (Some lenses are pretty bad stopped down that far, I don't know if it's diffraction or something else, or both.) I don't deliberately shoot at f/16 if I don't have to - clearly if I can accomplish the same goal at f/8 or f/11 I'll do that, just as with DOF. If I need to shoot wide open to yank a subject off the background, I'll do that, even if (say) an f/1.4 lens is nowhere near as sharp at f/1.4 as at f/8. (Few lenses are otherwise, but lots of people shoot wide open, don't they?) On the other hand, if the scene permits, of course I'll shoot at f/8 or f/11 to maximize the optical performance.

But don't take my word for it. Go try it! It costs almost nothing, and you'll know something for the future. It's clear that my standards are lower than the average Nikonian's, and perhaps you care more than I do.

The other thing to remember is that as long as you're not doing a sharpness shootout, you don't have someone else's f/8 (or whatever) sitting next to your print to compare against. Certainly I know of very few lenses that are poor at f/11, and not many are poor at f/16, and the ones that are poor at f/11 are poor at every other aperture too. Once you're viewing the result by itself, relative performance doesn't matter - unless of course you're in direct competition with someone else with better gear and suitably better technique. But more normally, especially for us amateurs, once you're not comparing, it's only a matter of making the image work, and that is a far easier task.

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Brian... a bicoastal Nikonian and Team Member

My gallery is online. Comments and critique welcomed any time!

Thanks, Brian, I was getting a bit of NAS reading about the D7000 until I came across this thread concerning the higher MP and defraction, and since I shoot landscapes at F11 got a bit concerned.

I think sometimes we get all involved in lab tests that just arn't a concern in real life situations.

Thanks again.

Jerry Jaynes
Great Smoky Mountains
of North Carolina

http://www.flickr.com/photos/by_jerry_jaynes/