Canon should create an Aperture + Shutter Priority Mode

[An drew]

The new 30D allows the ISO sensitivity to vary at 1/3 stops increment. In the past, with film as well as DSLR, the ISO is fixed (not auto mode) while we vary aperture or shutter speed to control the amount of light. Now that ISO can be changed electronically at 1/3 increments, there should be a mode to allow us to fix both the Aperture and Shutter Speed and the camera to automatically vary the ISO instead.

Such a mode would allow us achieve the dual objectives of using Aperture Priority as well as Shutter Priority. For example, we can fix the aperture at a particular f-stop that produces optimal (lens-specific) or purpose-specific results, as well as at a shutter speed that we need for the type of photography, eg. action or sports. We can then use software to remove the grains if high ISO was used.

As usual, setting in custom function can be changed to allow a safety shift.

What are your opinions?

[di0nysus]

gd idea!

[nightwolf75]

they did.

its call Manual mode....

[niki]

yea..i tot is manual? P&S camera also have have.. ...

[An drew]

Originally Posted by nightwolf75 they did. its call Manual mode....

Originally Posted by niki yea..i tot is manual? P&S camera also have have.. ...

In manual mode, the ISO does not vary by itself.

To avoid confusion, perhaps it should be called "Dual Priority" Mode.

Media sensitivity (ISO, ASA, etc) is the third variable in capturing light. With technology, we can vary it automatically.

Just like when we go from full manual to aperture priority and shutter priority with electronics for film. For film, the media sensitivity is fixed (although it can be pushed), but with digital technology, we can vary the sensitivity.

[tanjk]

Originally Posted by niki yea..i tot is manual? P&S camera also have have.. ...

He meant you set Av and Tv and the camera will set the ISO automagically to achieve correct exposure. And I think this is a good idea. Come on Canon!

Currently, M mode doesn't set the ISO mah.....

Regards,
JK

[jeremyftk]

Well... Perhaps you should consider going back to P&S if you want auto ISO... Quite frankly, I don't see a need for such a feature.

[kelccm]

I don't think letting the camera adjust the iso is flexible at all. From iso100 to 3200 is only about 5 stops(if I'm not wrong), and if you happen to set a small aperture with fast shutter speed in low light or vice versa, you'll find that the iso reading will be blinking most of the time, and will achieve under/overexposure easily.

With aperture priority or shutter priority, you'll get a much wider range to play with.

I would rather fix my ISO according to the lighting conditions or shooting conditions.

[Caspere]

I said the same thing on

http://forums.clubsnap.org/showthread.php?t=183494

Originally Posted by Caspere Part 3 .......... On ISO Steps Oh, the feature of allowing ISO adjustable in 1/3 stop steps instead of the 20D in 1 stop steps. In real world, I never have found a need to go in-between the standard ISO steps. {Banter:: I think its time Canon allow users to fix Aperture and shutter speed, and the body decide which ISO to use! Stepless ISO for exposure! And at the same time, allow a Custom Function Aperture/Shutter override in the event of hitting either the over/under on either scale for a perfect exposure.} .................. to be continued...

Actually Canon is already using the ISO shifting part on the FULLY PROGRAM (green) mode. Read the manual for more details.

SO I am very sure they can update the firmware for a C(ustom) mode if available just like the 5D.

[b18]

Originally Posted by An drew Such a mode would allow us achieve the dual objectives of using Aperture Priority as well as Shutter Priority. For example, we can fix the aperture at a particular f-stop that produces optimal (lens-specific) or purpose-specific results, as well as at a shutter speed that we need for the type of photography, eg. action or sports. We can then use software to remove the grains if high ISO was used. As usual, setting in custom function can be changed to allow a safety shift. What are your opinions?

and called .. ISO priority mode ?
The benefit of digital ... you can factor a new variable in .. sensor sensitivity

[An drew]

Originally Posted by jeremyftk See the world through the eye of an L lens... Simply amazing!

The performance of many primes or L lenses vary tremendously as the aperture varies, especially those with maximum apertures of f1.2, f1.4, f1.8, including the longer lenses at f2.8. At such wide apertures, a 1/3 stop can make a lot of difference to sharpness.

After spending so much money on L lenses, you would want to optimize the benefits in terms of sharpness, bokeh, etc at near-wide apertures. In a particular shooting situation, you will still want to control the shutter speed, be it fast or slow to achieve a desired effect. Such a mode will free you up to concentrate on the composition creatively or in focusing on capturing the action.

P&S?

[An drew]

Originally Posted by Caspere I said the same thing on http://forums.clubsnap.org/showthread.php?t=183494 Actually Canon is already using the ISO shifting part on the FULLY PROGRAM (green) mode. Read the manual for more details. SO I am very sure they can update the firmware for a C(ustom) mode if available just like the 5D.

Hopefully we can create more awareness on this idea and see it happen one day!

[solarii]

I doubt this mode will be popular or practical.

Most photographers will want control over ISO to control noise. Noise removal routines degrade images quality no matter how good the process. I would never let the camera decide on ISO for me.

[An drew]

Originally Posted by solarii I doubt this mode will be popular or practical. Most photographers will want control over ISO to control noise. Noise removal routines degrade images quality no matter how good the process. I would never let the camera decide on ISO for me.

I guess different people will have different needs and preferences. Some will remain purists. There was a time when I did not even want aperture priority or shutter priority and used an FM2 for many years.

[jeremyftk]

Originally Posted by An drew The performance of many primes or L lenses vary tremendously as the aperture varies, especially those with maximum apertures of f1.2, f1.4, f1.8, including the longer lenses at f2.8. At such wide apertures, a 1/3 stop can make a lot of difference to sharpness. After spending so much money on L lenses, you would want to optimize the benefits in terms of sharpness, bokeh, etc at near-wide apertures. In a particular shooting situation, you will still want to control the shutter speed, be it fast or slow to achieve a desired effect. Such a mode will free you up to concentrate on the composition creatively or in focusing on capturing the action. P&S?

You're not making sense here. And my stand is similar to solarii, that's why I said, if you want such features, go back to P&S. What does my using of L lenses have to do with this?

[ibs]

Auto ISO?

Prolly won't do any good to me, because I always work on lowest ISO setting possible for optimum quality. Furthermore I can recover more details from lower ISO RAWs than those shot on a higher setting.

However, action shooters might find auto ISO useful.. but I'm not really too sure...so let's hear what they have to say.

[Zerstorer]

Originally Posted by ibs Prolly won't do any good to me, because I always work on lowest ISO setting possible for optimum quality. Furthermore I can recover more details from lower ISO RAWs and those shot on a higher setting.

Think of this in another way:

With the shutter speed and aperture set to the desired setting, auto-iso will allow you to take the shot at the lowest iso needed for a proper exposure. This when coupled with good metering techniques will allow you to optimize the image quality of your shots when shooting in bad lighting conditions.

i.e You won't have to consciously fight with changing exposure settings and can just concentrate on the composition. Your ISO will never be a touch too high or too low but just what is needed to get the exposure you set.

I always try to use auto-iso in challenging light, but I'm not using Canon.

[An drew]

Originally Posted by jeremyftk You're not making sense here. And my stand is similar to solarii, that's why I said, if you want such features, go back to P&S. What does my using of L lenses have to do with this?

Agreed. P&S.

Sorry if I gave the impression of referring to your L lenses. I do not know what lenses you own, it is just that many L lenses have wide apertures, which such a Mode, as explained earlier, can help to optimize.

[agape01]

Originally Posted by Zerstorer Think of this in another way: With the shutter speed and aperture set to the desired setting, auto-iso will allow you to take the shot at the lowest iso needed for a proper exposure. This when coupled with good metering techniques will allow you to optimize the image quality of your shots when shooting in bad lighting conditions. i.e You won't have to consciously fight with changing exposure settings and can just concentrate on the composition. Your ISO will never be a touch too high or too low but just what is needed to get the exposure you set. I always try to use auto-iso in challenging light, but I'm not using Canon.

That is true. But most people will not use it.

[solarii]

Originally Posted by Zerstorer Think of this in another way: With the shutter speed and aperture set to the desired setting, auto-iso will allow you to take the shot at the lowest iso needed for a proper exposure. This when coupled with good metering techniques will allow you to optimize the image quality of your shots when shooting in bad lighting conditions. i.e You won't have to consciously fight with changing exposure settings and can just concentrate on the composition. Your ISO will never be a touch too high or too low but just what is needed to get the exposure you set. I always try to use auto-iso in challenging light, but I'm not using Canon.

A valid point. Auto ISO will allow you to optimize image quality by selecting the lowest usable ISO based on the selected Tv/Av.

However, it does give you an additional variable to worry about... you'll have to watch yr ISO, in additional to changing your Tv/Av, esp. in low light environments.

With the current exposure modes available, most photographers will make a creative decision (noise vs. extra stops) when setting ISO, and leave it at that. The main concern would then be balancing Tv/Av values to attain the desired effect. Auto ISO would introduce a third variable that would need to be considered for each frame, which I feel is counter-intuitive.

So you may not be setting the "optimal ISO" is you select it manually. But by fixing the ISO (and hence the amount of noise generated in an image), you'll have 1 less thing to worry about during shooting.