20D 1/3rd ISO increments in Auto?

[EpHeSuS]

My parents recently took the 20D to New Zealand for a few days and they were using it in Full Auto Mode (green box).

They came back today and I was looking at the shot settings for the photos and noticed that some of the photos were shot at ISO250 and 320. I'm wondering - If the camera can shoot in 1/3rd ISO increments in Auto mode, then why didn't Canon allow it in modes where the user can select it them selves?

Wonder if we can make a firmware hack to give us 1/3rd increments :D

[DocFrankenstein]

Because they're cheap bastards... that's why.

[Mark_Cohran]

It is available on the higher end models such as the 1D Mark II - I know I can set ISO manually in 1/3rd increments on mine. The ability to vary it by 1/3rd increments on the 20D seems to be there as evidenced by your observations, so I think Doc has it right.

On the other hand, how much value added is the ability to set ISO in 1/3rd increments? I shot just fine with the 20D. I never stopped and said to myself, "Damn, if I could just set this ISO just a tad bit higher." So, maybe that was Canon's thinking as well. In full auto, the finer variations of ISO probably make it easier for the computer to calculate a more exacting exposure, but most photographers use shutter speed and aperture as their primary means of fine exposure control, and ISO is usually set to the lowest value to achieve those settings given the conditions of light.

Mark

[ScottE]

This may be a really good solution for a problem that many of us never knew we had. I am sure it is a good solution, but I still haven't figured out what problem I have that this will solve for me.

[ghocking]

I find 1/3 stops ISO on the 5D one of its best points.

[DocFrankenstein]

"Damn, if I could just set this ISO just a tad bit higher."
Those pro fotogs with pro bodies are left burdened with such difficult decisions...

I'll stop being sarcastic for now. :D

[tim]

The only advantage I can see is being able to choose values like ISO 1000 or 1200 instead of 1600, but then again when i'm shooting most of the time i'm in such a mad rush I don't have time for such fine grained decisions. To me the 20D system is fine, and possibly an advantage - even though i'm sure the 1 series lets you choose full stops if you want.

[Wilt]

Hey guys, where is the beef??? ISO values are set by international standard, and they are 1/3 EV apart. And Canon 20D can be set via Custom Function 6 to increment either in 1/3 or 1/2 EV increments for shutter speed, aperture, exposure compensation, AEB, etc. READ the MANUAL!

[Jon]

Hey guys, where is the beef??? ISO values are set by international standard, and they are 1/3 EV apart. And Canon 20D can be set via Custom Function 6 to increment either in 1/3 or 1/2 EV increments for shutter speed, aperture, exposure compensation, AEB, etc. READ the MANUAL!
Yes, but even with that CF, your ISO can only be varied in whole steps. I tend to agree with others - it's not really a very useful feature, since you have other ways of fine-tuning exposure, although I can imagine situations where I might want to use it (match a film ISO, chiefly).

[Wilt]

Jon, ISO values are standardized by international agreement at 25, 32, 40, 50, 64, 80, 100, 125, 160, 200, 250, 320, 400, 500, 640, etc. and each one is 1/3 EV apart from each other. To be able to chose in between is to go against and international stardard!

Different is the question of choosing an in-between shutter speed or aperture. Lenses were made a very long time ago with diaphrams that are infinitely variable and no click stops, but markings on the lens...you chose 'about f/4'. With digital rather than analog settings, infinitely variable apertures are more problematic, but photography standardized on 1/3 or 1/2 EV increments years ago. But nothing prevents finer increments on shutter and aperture...my Bronica ETRSi AE-III meter can measure and set 1/12 EV increments for exposure but the ISO dial is per the international standard.

[Atlasman]

Yes, but even with that CF, your ISO can only be varied in whole steps. I tend to agree with others - it's not really a very useful feature, since you have other ways of fine-tuning exposure, although I can imagine situations where I might want to use it (match a film ISO, chiefly).

ISO adjustments would be more useful if you can set them while framing—this means the ISO values need to be displayed in viewfinder.

[elTwitcho]

Jon, ISO values are standardized by international agreement at 25, 32, 40, 50, 64, 80, 100, 125, 160, 200, 250, 320, 400, 500, 640, etc. and each one is 1/3 EV apart from each other. To be able to chose in between is to go against and international stardard!

Different is the question of choosing an in-between shutter speed or aperture. Lenses were made a very long time ago with diaphrams that are infinitely variable and no click stops, but markings on the lens...you chose 'about f/4'. With digital rather than analog settings, infinitely variable apertures are more problematic, but photography standardized on 1/3 or 1/2 EV increments years ago. But nothing prevents finer increments on shutter and aperture...my Bronica ETRSi AE-III meter can measure and set 1/12 EV increments for exposure but the ISO dial is per the international standard.

Yes, and the 20D only allows you to chose in full stop increments, as in 50,100,200,400,800,1600... Nobody is asking to set their ISO in less than 1/3 or 1/2 increments here, they're asking why they CAN NOT set their 20D using 1/3 or 1/2 increments because they CAN ONLY change it using full stop increments

[ScottE]

I am asking why I would need less than full stop increments, but I learned photography in the film world where you had to live with one ISO for the full 36 frames, unless you went through an annoying process of respooling a partially completed roll, retreiving the tag end and reloading and advancing to where you left off when you wanted to complete the roll.

Film choice was usually limited to two or three films, for example I carried ISO 50 Velvia and ISO 100 and 400 Provia. If you wanted to push a film, you usually did it in one stop increments to make it easier for the technicians to push the development.
The ability to change ISO settings at any time I want in one stop increments with digital is such a luxury that I can't imagine needing anything more.

[Rob612]

ISO adjustments would be more useful if you can set them while framing—this means the ISO values need to be displayed in viewfinder.

That is what happens with the 5D and the 1DMkIIN :)

[PaulB]

We are at the 'you get what you pay for' point again. If you NEED 1/3rd. stop ISO settings you will have to pay for it. If everything was included on every Canon body then we would have? Let me see now....one FF sensor body! Yes a 1DsMk2. If you couldn't afford to buy that then tough, you couldn't afford to use Canon at all.
Which would you prefer, a range of affordable bodies, one of which may just do most of what you need at a price you can afford and justify or just the one - which does everything but which you have to sell the house, car and kids to buy?

[Wilt]

>> 20D only allows you to chose in full stop increments, as in 50,100,200,400,800,1600... Nobody is asking to set their ISO in less than 1/3 or 1/2 increments here...<<

Sorry for my failure to understand the real question!

[JMHPhotography]

I am asking why I would need less than full stop increments, but I learned photography in the film world where you had to live with one ISO for the full 36 frames, unless you went through an annoying process of respooling a partially completed roll, retreiving the tag end and reloading and advancing to where you left off when you wanted to complete the roll.

Film choice was usually limited to two or three films, for example I carried ISO 50 Velvia and ISO 100 and 400 Provia. If you wanted to push a film, you usually did it in one stop increments to make it easier for the technicians to push the development.
The ability to change ISO settings at any time I want in one stop increments with digital is such a luxury that I can't imagine needing anything more.

Up until recently, I have been shooting film. I know back in the day when you didn't have the power film advance/respool systems... the full manual days. You could listen to the back of the camera for that little sound of the tab releasing the takeup reel and stop there and you wouldn't need to retreive the leader tab. Wasn't that great? lol. My Rebel T2 advances the film all the way out when you first load it, and respools as you shoot. But I wish that I could hit that film rewind without losing that leader tab into the cartridge.

Oh and as for 1/3 stops on ISO, I think that with 1/3 stops on both aperature and shutter, the thinking must have been... who would use it when there is already so much creative control. I'm like this too, but we've reached a time where the more bells and whistles a gadget has the better. Even when some of those bells and whistles would hardly ever get used.

[PaulB]

But I wish that I could hit that film rewind without losing that leader tab into the cartridge.
.
Ah, if only you had a 1 series film body; you can set them to do that!
As for all the bells and whistles, I agree with you - there are more settings in my 1DMk2 than I know what to do with, what with CFs, PFs, parameters, custom white balance, colour spaces..........don't get time to take pictures for fiddling with the camera. Now where's that laptop to set PF99? Or is it CF55? Or...........

I also thought "forkball is just down the road from me in Wakefield" - then I realised; wrong country! Oh, the internet is a wonderful thing.

[JMHPhotography]

Ah, if only you had a 1 series film body; you can set them to do that!
As for all the bells and whistles, I agree with you - there are more settings in my 1DMk2 than I know what to do with, what with CFs, PFs, parameters, custom white balance, colour spaces..........don't get time to take pictures for fiddling with the camera. Now where's that laptop to set PF99? Or is it CF55? Or...........

I also thought "forkball is just down the road from me in Wakefield" - then I realised; wrong country! Oh, the internet is a wonderful thing.

lol.. yeah, there's a big giant pond between us, but hey. God bless the internet and Al Gore for inventing it. :lol:

Yeah, I guess if I wasn't so poor when I bought my Rebel, I could have gotten the 1 series film body... and found that out. I guess the omission from the Rebel and other consumer/prosumer line bodies is because most amatuer or people who use them in a non professional capacity wouldn't have a need to swap out a film mid roll.