ISO Question

Normally, I set my ISO manually and make necessary adjustments as conditions call for it.

I have not tried the Auto - Range feature on my 5DIII where you set the minimum and maximum, and let the camera decide.

I'm inclined NOT to use it, but curious if anyone else has tried it with any success.

If so, has it helped? Do you like it?

It works astonishingly well. I always use it when in Av without a flash. You'll still need to adjust EC in most cases, however.

It work well in Av mode.
That said, I rarely use Auto ISO. Just prefer to set it myself. Also, half the time I am in M mode and Auto ISO doesn't cut it.

nicksan wrote in post #16433469
It work well in Av mode.
That said, I rarely use Auto ISO. Just prefer to set it myself. Also, half the time I am in M mode and Auto ISO doesn't cut it.

Yes, but just wait until the 5D3 gets EC with auto ISO!

I use Auto ISO in Av mode 95% of the time now. With the ability to set the minimum shutter speed, I don't see why you wouldn't use it. It has saved a few shots here in there when lighting changes dramatically and I don't notice my needle.

You should definitely play around with it, if you shoot in Av or Tv. While its somewhat usable in M mode, it works better in those program modes.

can't give my camera any way to do anything on its own so I always shoot in manual.
Once you shoot a lot, you can just switch settings on the fly without looking,while you are shooting.
I rather have a shot at ISO 100 and 1/160s than ISO 1000 at 1/800s

dmitrim wrote in post #16433897
I rather have a shot at ISO 100 and 1/160s than ISO 1000 at 1/800s

Which is precisely what Auto ISO does

I found it annoying for post processing, every image is different. I shoot manual, much much easier for post processing.

Trent Gillespie wrote in post #16433900
Which is precisely what Auto ISO does

now think about it again...
next time you roll your eyes, make sure you can back it up

puggle wrote in post #16432720
Normally, I set my ISO manually and make necessary adjustments as conditions call for it.

I have not tried the Auto - Range feature on my 5DIII where you set the minimum and maximum, and let the camera decide.

I'm inclined NOT to use it, but curious if anyone else has tried it with any success.

If so, has it helped? Do you like it?

I've started to use it with my 5D3 this past year for events where lighting changes varies frequently (think cousin's outdoor resort wedding from late afternoon to evening in Cancun). That worked splendidly. There are some high ISO shots that needed noise reduction, but I can batch process those in Lightroom.

I just got the 5D2... not sure how well Auto ISO works on that.

dmitrim wrote in post #16434725
now think about it again...
next time you roll your eyes, make sure you can back it up

I'm pretty sure that auto ISO tries to keep the ISO as low as possible until the required shutter speed drops below the set limit. Then the ISO goes up one stop. Is this not correct?

dmitrim wrote in post #16434725
now think about it again...
next time you roll your eyes, make sure you can back it up

Auto ISO works in Manual exposure mode as well. It selects the lowest ISO possible, while retaining an adequate exposure.

Quite agree, shoot manual, then batch processing is so much quicker

frugivore wrote in post #16435527
I'm pretty sure that auto ISO tries to keep the ISO as low as possible until the required shutter speed drops below the set limit. Then the ISO goes up one stop. Is this not correct?

It may well be correct, but dmitrim said that he always shoots in manual. As soon as you set auto ISO you are no longer shooting in manual, you are in an auto mode that will adjust exposure as it sees fit, and can be altering it based on a change in the tone of a background or subject, whilst the actual exposure wanted has NOT changed.

Therefore, no, auto ISO does NOT do the same as shooting manual.

Trent Gillespie wrote in post #16435539
Auto ISO works in Manual exposure mode as well. It selects the lowest ISO possible, while retaining an adequate exposure.

No, it doesn't.

Yes, you can set the auto ISO with the mode set to "M", but it is then no longer manual, as the camera is altering the exposure. Shooting "manual" means setting all three components yourself and shutting the camera out of the decision making process. "M with auto ISO" is another auto mode like Av or Tv, that just happens to use the "M" setting to access it. It is not "manual".

To go back to the OPs question. I don't like auto ISO, but I accept that it does have uses. I never use it on my 40D (which I believe has it in a more primitive form) and have used it twice on my 5DIII in over a year of ownership. Both times I used it I was shooting in a theatre and stage lighting was altering exposure significantly from shot to shot, so manual was not an option. I wanted the camera to handle exposure for me, but needed the aperture fully wide and wanted to set my minimum shutter speed myself. So I set the aperture wide open, shutter speed where needed from shot to shot (slower for stationary actors, faster for dance routines) and let the camera adjust ISO to cope with the stage lighting.

That allowed me to keep ISO as low as possible, and it was really useful in that situation. In other situations though, I am happier in manual, or using Av or Tv with EC, depending on the requirements.

As with all such features, auto ISO is a tool in the toolbox, it may or may not be one that you want / need to use much, but it does have its uses and can perform a function that cannot be achieved another way.

By the way... what some people might find useful is that, in the menu settings, you can select your preferred maximum ISO value. For example, if you know that you can tolerate ISO 1600, but hate the look of 3200, you can tell your auto ISO never to go beyond 1600. I know this is available on the 7D and 5D3. I just got the 5D2 and I haven't looked for it in the menu settings yet. Not sure about other bodies.