> >Wow, I must have missed that in the manual - I have a D700 - >please explain how I can shoot at ISO 100 ? I would like to do >this for landscapes or architecture or bright sunny days? >thanks, Debra >
I don't know where it is in the manual, but somewhere there is an extended ISO mode or something like that.
You might not want to shoot at ISO 100, compared to ISO 200. According to some testing, you get decreased dynamic range at ISO 100.
According this analysis at dpreview:
* You get "only" 7.5 stops at ISO 100. (assuming that the D3 and D700 yield the same results and are set up the same way.)
* You get about 8.5 stops of DR from ISO 200 through ISO 1600.
Thanks Brad and Jon, I will try this on my D700 at home. I am in a hotel in Apex, NC for the two Nikonians' workshops this weekend, on Lighting and then Capture NX2(with a D2X, as the D700 was not listed in the equipment desired for attendees so brought something well known).
Another reason that I have shot low ISOs (remember when it was called ASA speeds for film?) is to print large with such small grain that it is spectacular, for example, I shot a sunrise with ASA 25 speed and my enlargement had no grain at all. I suppose low ISO speeds equal low ASA speeds(film) for effect. Debra
Thank you. Aside from the lower Exposure Value that you can use, and given the slightly lower dynamic range, is there any technical merit to shooting at ISO 100? Do you get better colors, better (finer) tonal transitions, less noise, etc?
For example, with some cameras, such as my D70, I get some noise in otherwise beautiful clear daylight cyan skies at ISO 200. (Of course at four years of age, that camera is now ancient.)
I have to disagree. The amount of fill flash that is needed is not determined by any camera setting. Rather, it is a matter of the strength of the ambient light. Since by definition you are trying to "fill" the shadows of your subject, doing so depends on the amount of illumination of the non-shadowed part.
What is true is that you tend to need a low ISO for fill flash because your camera's sync speed (non-auto FP) limits how fast your shutter speed can be. "Sunny 16" says that at ISO 100 and 1/250, you need an aperture of about f/11 in bright sunlight. At ISO 200, it's more like f/16.
So, yes, you may want to shoot ISO 100 for fill flash, but it's not to give your flash greater distance. And for regular, non-fill, flash, it is a higher ISO that gives greater flash range.
Jon, the amount of fill flash that is needed is most certainly determined by the camera setting! Aperture determines a flash unit's maximum useable distance. If you're photographing a group of people outdoors at f/16, you have to be closer to them to get the same amount of fill light that you could get from a greater distance at f/11, since it's likely that a camera-mounted flash would be putting out full power to cover that small f/stop and distance.
One of the things I like most about my D1X is the low 125 ISO and high sync, which lets me shoot fill flash at 1/500 at f/8. I can shoot fairly large groups of people even 15 feet away and still get fill from the flash.
>Jon, the amount of fill flash that is needed is most >certainly determined by the camera setting! Aperture >determines a flash unit's maximum useable distance.
. . . within the technical limits/rated range of the flash. But it doesn't magically change the technical limits of the flash, which is what the other poster seemed to be talking about, and what Jon commented on. I think. That's how I read it all.
Suppose, for example, you want to fill the shadows on a face with an amount of light that makes the shadows one stop below the sunlit part of the face. To do that, the amount of light you need is dependent on the brightness of the sunlight on the face. It is purely a ratio of the main light (sun, in this case) to the amount of fill wanted.
The amount of flash power you need to achieve that amount of light on the face is dependent on flash-to-subject distance but is not dependent on camera settings. With the flash set up in this example, if you adjust your camera for f/16 and the sunlit parts of the faces are properly exposed, the filled parts will be exposed one stop below. Similarly, if you set aperture to f/11 and adjust shutter to properly expose the sunlit parts, leaving the flash set to the same settings and at the same distance, the filled part will still be one stop down.
So again, the amount of fill flash needed is dependent only on the brightness of the sun (or whatever the main light source is).
Now, when the flash is the main illumination, it's a wholly different case. Then there is direct relationship between camera settings and the amount of flash needed. But not for fill flash.
I think we're talking about two different aspects of the same topic! The original post was why use ISO 100. And a primary reason to do so is to allow as wide an aperture as possible at the 1/250 sync speed to extend the useful range of your flash for fill. And as you've stated, there are a number of techniques to use for fill flash.
>I think we're talking about two different aspects of the same >topic! The original post was why use ISO 100. And a primary >reason to do so is to allow as wide an aperture as possible at >the 1/250 sync speed
Jon, I'm right with you up to this point.
> to extend the useful range of your flash >for fill.
That's where we part company. I continue to insist that for fill, the range of your flash depends on the intensity of the main light, the distance form flash to subject, and the amount of fill you want -- and it has nothing to do with camera settings. Sorry.
Got it, Jon! I was careless to use "EXTEND the useful range..." when I should have said "ATTAIN the useful range...", though I was using it in the context of dropping from 200 ISO to 100 ISO. Also, you had assumed that the photographer would be already shooting at the widest f/stop possible for 1/250 and the main light, so yes, beyond that the camera settings aren't a factor. Then the maximum useable distance of a flash for fill would be determined by the photographer based on what he considers his minimum acceptable fill ratio, probably 1:3 or 1:4.
Every camera sensor & CPU design results in a base ISO rating at which the component combination operates optimally. Purely from the standpoint of lab/engineering and technical image quality analysis, ISO200 is the best setting in the D700.
The point is that equating film ISO and its impact on image quality (lower film ISO means finer grain, ergo better technical image quality which means ISO100 is better than ISO200, ISO64 is better than ISO100 and so on) with a sensor/CPU combination optimized for ISO200 is inappropriate.
I think the photography industry in general has done a poor job of lifting film ISO/digital ISO comparative ratings off our shoulders. The standards bodies have tried to do comparative ratings, but the task is impossible due to the wide variety of engineering approaches in sensor/CPU and the constantly shifting (improvements) in digital noise reduction and control.
Sun 10-Aug-08 06:15 PM | edited Sun 10-Aug-08 06:16 PM by brad_nikon
>The point is that equating film ISO and its impact on image >quality (lower film ISO means finer grain, ergo better >technical image quality which means ISO100 is better than >ISO200, ISO64 is better than ISO100 and so on) with a >sensor/CPU combination optimized for ISO200 is inappropriate. >
It's a valid and very appropriate _question_, which is what I was trying to pose and not make assumptions. The heart of my question is what happens?
Apparently, dynamic range is decreased.
What happens to color, contrast, noise, saturation, etc?
Afterall, if you go higher in ISO from the base, there's a tendency to get more noise, more "grain-like" appearance, lower dynamic range, muted colors, etc. Does the same occur when decreasing ISO from the base ISO 200?
To produce a shallower depth of field when pushed up against max flash sync speed (Lowering the ISO 1 stop allows you to open up the lens 1 stop). This is useful when using fill flash for outdoor portraits in bright light...