Is ISO a primary control

I think something has slowly happened in digital photography which we haven't really noticed - that ISO has emerged as a primary camera control.

In the days of film you were more or less stuck with the ISO of the film in your camera. You could 'push' it a couple of stops (ie underexpose and change the way you developed it) but that was about it.

Now we seem to have a permanent third option to add to aperture and shutter speed. So should cameras be redesigned to make it much easier to change ISO in manual mode? And will we think of it as cheating and taking away from the skill of the photographer if we leave our cameras on auto-ISO?

These are the things I think about when driving to work.

Yes these days it definitely is.

Shutter speed & aperture both have effects on the image displayed (DOF & movement) ISO can then be the tool to get the exposure right!
Unfortunately it's not one I think of adjusting often enough - shutter & aperture are habits from film days, but ISO needs me to think (& then dig into the menus).

I've frequently been caught out by auto-iso. If I look at a scene (or view a shot) and decide I need exposure compensation - the ISO drops to 200.
Most commonly this is in low light work, where a quick Ap shot comes out under exposed (perhaps from a street light to close to the centre) - tweak exposure compensation 1 stop & take again - suddenly shutter speed is 8 times as long & useless. The shots wasted & I have to dive into the menus, (hoping the subject hasn't gone before I'm finished) then take it again.

Mike

I agree entirely. The industry is slowly waking up to the modern age, and Pentax is in the front here with the TAv and Sv modes. The high ISO capabilities and high pixel counts really ought to start freeing us from the traditional issues of speed and need for large apertures (other than for dof control). I often use TAv when photographing the kids as I want to ensure that speed stays above 250 (they run around a lot), whilst I stay between 3.5-11. Let the camera adjust ISO, no problem!

I also use the DA40 as a very compact walk-around, knowing that I can happily crop by 50% and get a good telephoto of 80mm for most of my shots which will be viewed on computer screen/6x4. Same reason I haven't spent money on a good 200+ when I can crop the 50-135mm.

Tony

I have ISO readily available via the Fn menu on the K20D bodies. And I use it a lot.

I don't feel the need for a separate dial though, but maybe that's just habit. If there were such a dial, would it improve things?

Even though it doesn't seem to be a problem, as digital imaging changes photography we should look at everything again.

Yes it has and that is why I have it set on the front dial of my K20D when in Av mode (which I use 95% of the time). I am less bothered by the shutter speed for most of the images I take especially as I am not tripod-averse so I will adjust the ISO to allow me to use the aperture I wish.

K.

For ages I didn't know about controlling ISO in M mode by holding the OK button and turning the front dial (on a K20D). Once I learnt that trick (is it in the manual? I never found it) it greatly simplified things and allows quick control of all 3 variables.

On the K7 all modes except Green, TAV, Movie, Just press the ISO button and twiddle the rear dial hey presto the ISO changes. CHEERS Vic.
PS See page 90 in operating manual. Vic.

And Pentax have had the forsight to include modes which fully utilise ISO

And yes I also have my front dial set for ISO on the 10&20D, might give Tims trick a try though.

I think ISO has always been a primary control, but we had little control over it.

Aperture, shutter speed, and ISO are the only variables affecting exposure.

In the digital age we can expose each frame as we wish, unlike the days of film where you had to expose a whole roll using (more or less) one ISO setting dictated by the roll you had in the camera at the time.

On my K10/20D's which I use in Av mode most of the time, I have ISO on the front eDial. Suits me sir.

Kris also has it there, so am i the only one that has EV compensation on the front wheel?
I used that a lot more with Av to properly expose a photo because ISO has no effect on that in Av and you can access the ISO the same as in any other mode by pressing the OK button.

I don't think we should be snooty about Auto-ISO. ISO doesn't bring anything to the party, unlike aperture and shutter speed. ISO just facilitates.

Auto ISO gives a lower threshold to your shutter speeds, at which point the camera will begin to raise ISO rather than go for long exposures. This is usually convenient when shooting hand held, when you don't really want to dive into the menu (or even spin the front wheel) to get the shot. And these days there is much less image degradation at higher ISO to worry about.

I agree that ISO, whilst always part of the 'holy trinity', has become a primary control in the digital age as unlike the film days we now have the freedom to change it quickly and at will on a per-shot basis.

On the K10 and K20 I used OK button + front wheel in Hyperprogram mode to adjust quickly, whereas with the K-x I feel forced more into film ways, ignoring ISO adjustments unless absolutely necessary. I have found one wheel and a bit of menu diving to be increasingly frustrating this last year or so.

No experience of the K7/5 body as yet, just hope there's a similar quick and easy ISO change as the K10/20 when the inevitable lure of the upgrade happens

digitalCG. See my earlier comment on K7. CHEERS Vic.

It's got nothing to do with me

Cheers Vic - I like the 'old' way of doing things as my thumb is by the OK button anyway for shifting focus points, but had guessed the ISO button plus a wheel (configurable?) would probably do it.

Guess I meant to say 'an equally efficient way' of changing ISO. This would take some getting used to but am prepared to try if someone will just lend me their K-5