How to influence ISO vs shutter speed choices (auto ISO)?

[Lee R]

If I was shooting a body that didn’t have a third dial wheel to assign ISO and had to press a button to go into a menu to change ISO, I would probably use auto ISO. I was thinking that rear dial turned on Nikon as it has been a number of years since I’ve shot Nikon and I forgot about this lack of a third dial wheel limitation. Once you get used to having the rear dial wheel set for ISO like you can on a Sony body it is second nature and practically instantaneous to make adjustments to shutter speed, aperture and ISO to get a good exposure no matter the circumstances or changing lighting conditions no matter how fast things change. 95% of the time I’m shooting wide open (set it and leave it), I know the shutter speed I need based on the focal length of the lens and whether I’m shooting something stationary or moving to get a sharp shot (set what I need and leave it) and in full manual the ONLY setting I’m having to change and can do so practically instantaneously is changing ISO with my thumb spinning the rear dial which is set to ISO. This allows you to shoot in any type of circumstance and only have to worry about changing ISO. Bought as simple and fast as it gets and the exposure is always consistent……..always consistent. If I start getting past the “clean ISO” range of a camera which these days is very very high I might have to mess with changing aperture or shutter speed but this rarely occurs. But if you don’t have that third dial like on a Sony I can see where auto ISO would be useful. Still wouldn’t trust it, but a necessary evil of sorts.

I can literally do exactly the same thing on my Z8, no menu diving required. Set the aperture/shutter, click ISO on top with forefinger and the rear dial spins ISO.

The top ISO button is just a toggle to switch the rear wheel from shutter to ISO and vice versa. It's extremely fast. There is no menu to go into for this. There is no menu's needed to turn auto ISO on or off or to adjust the auto iso range. All of this is quick and easy via the buttons on the camera without touching a menu.

 

[TomRC]

I can literally do exactly the same thing on my Z8, no menu diving required. Set the aperture/shutter, click ISO on top with forefinger and the rear dial spins ISO.

The top ISO button is just a toggle to switch the rear wheel from shutter to ISO and vice versa. It's extremely fast. There is no menu to go into for this. There is no menu's needed to turn auto ISO on or off or to adjust the auto iso range. All of this is quick and easy via the buttons on the camera without touching a menu.

I was thinking you could just been out of the Nikon ecosphere some years now. Always liked Nikon!

I trust my cameras to carry out a lot of complicated stuff but when it comes to the exposure triangle I only trust me, myself and I to get it right and this can all be done in an instant via full manual mode if you set your camera up right no matter how fast lighting or other circumstances change and you know the results will always be consitent.

 

[PhotoLover]

If I was shooting a body that didn’t have a third dial wheel to assign ISO and had to press a button to go into a menu to change ISO, I would probably use auto ISO. I was thinking that rear dial turned on Nikon as it has been a number of years since I’ve shot Nikon and I forgot about this lack of a third dial wheel limitation. Once you get used to having the rear dial wheel set for ISO like you can on a Sony body it is second nature and practically instantaneous to make adjustments to shutter speed, aperture and ISO to get a good exposure no matter the circumstances or changing lighting conditions no matter how fast things change. 95% of the time I’m shooting wide open (set it and leave it), I know the shutter speed I need based on the focal length of the lens and whether I’m shooting something stationary or moving to get a sharp shot (set what I need and leave it) and in full manual the ONLY setting I’m having to change and can do so practically instantaneously is changing ISO with my thumb spinning the rear dial which is set to ISO. This allows you to shoot in any type of circumstance and only have to worry about changing ISO. Bought as simple and fast as it gets and the exposure is always consistent……..always consistent. If I start getting past the “clean ISO” range of a camera which these days is very very high I might have to mess with changing aperture or shutter speed but this rarely occurs. But if you don’t have that third dial like on a Sony I can see where auto ISO would be useful. Still wouldn’t trust it, but a necessary evil of sorts.

No, my comment which you deleted part of, was unclear or you misread it; you hold down the ISO button and (the way I have my camera set up) the rear dial then changes ISO. It's quite fast. Needing to use a menu is not the problem.

The root of my disagreement is the assertion that manual + auto ISO is not a pretty good way to manage the exposure triangle. I think it is.

For example suppose I'm taking a picture of a critter in shade. It's not in flight, but neither is it motionless plus I have a long lens on the camera. Alas, I have less light than I want. I will often use the technique (suggested by the site owner) of taking a shot at say shutter speed 400, shutter speed 320, shutter speed 250 trying to get a sharp shot with the lowest ISO. In full manual, I would need to change two settings for each shot. In manual + auto ISO, I'm dialing down the shutter speed while watching the ISO also go down.

Or I switch from a perched bird to incoming BIF. All I have to do is bump the shutter speed ... one setting, versus changing shutter and ISO. I can change one setting faster than two.

It helps of course that I'm shooting in RAW mode and that the Nikons (and most modern cameras) are pretty much ISO-invariant. This helps with full manual as well if one does not nail exposure exactly.

Personally I find it almost impossible to get a completely consistent exposure across changing light and target conditions. I often am underexposing (EC up to -2 stops with some birds) to avoid blowing highlights. Sure, if I have a constant environment I can get exposure very close every time. With landscapes I'm pretty darn unhappy if my exposure is not about right (even then with a wide dynamic range scene I might underexposure to preserve highlights).

This is all a long way of saying that sure, full manual can work. But manual + auto ISO is widely used and very very useful. And I believe it faster to use across changing conditions/subject than full manual for most people. It might not be for you. But it's a good, often excellent, solution in many situations.

 

[Unscript]

Back in the day we had to use a spot meter on grass or something kinda close to middle gray, take a shot, check the histogram (chimping), make adjustments and repeat until the histogram looked to be in the ballpark. Today shooting full manual is soooo much easier with mirrorless. Just keep a histogram viewable on the live display at ALL TIMES. The histogram IMO is the most valuable tool in your camera, only go by it and never what the exposure looks like on the live display. The live display is great and use the live display to get a general idea of where you are but verify you don’t have clipped highlights or crushed shadows by looking at the histogram.

I remember the old days when we had to estimate the light and focus with the split prism (sometimes, I miss that). It sure is easier with a mirrorless, but it can be misleading, too, as this little experience showed.

I agree the histogram is a nice tool when the lighting conditions are tight, but I usually have no issue with the EVF. Now that the display shows exactly what the sensor gets, it's easy to estimate any under- or over-exposition, and the quality of the Z6III EVF is outstanding. Though I never had an EVF before for comparison, since my previous was a classic DSLR.

And again, in this case, there was no chance of clipping since the fog made squeezed the dynamic in the middle of the range. The problem was with the weird choice of speed vs ISO, which the histogram wouldn't have shown. There are already quite a few things to check before each shot, so I'd rather not add more to it if I can do without (unless I have all the time in the world). It also blocks a part of the image, so I must switch viewer modes to get to it.

EDIT: I did use it today when taking shots of a snowy landscape facing (or almost) the sun.

But, you need to be able to adjust ISO without having to go into a menu. Very easy on Sony by assigning ISO to the rear dial. Can’t remember if the rear dial looking “thing” on Nikon bodies spins or not but it is best for time sake to adjust ISO by spinning a dial similar to how you adjust shutter speed and aperture. Once you don’t have to go into a menu for ISO you can dial in your exposure in seconds and then you don’t have to make any changes unless lighting changes but I always have my eye on the histogram. Simple, fast, consistent.

There's both a front and back dial, though Nikon has inverted a lot of things, like the rotating direction of the lens and the front/back dials functions. I inverted them back to get the usual aperture at the back of the camera, in front of me, and the speed at the front (which is cumbersome to spin - bad ergonomics, there). The ISO can be changed like with most other cameras by pressing ISO and using one of the dials, and it can be set to manual/auto similarly with the other dial. It's pretty much muscle memory at this point, so no issue.

The only problem was my trying to rely on both auto ISO and "auto" shutter speed, unlike what I used to do so far. Or, rather, not knowing the quirks of how the camera makes its decisions. Which made me curious about how others here were setting up their camera.

 

[Unscript]

That really is the key. No matter what level of exposure automation you use you really do want to keep an eye on:

- ISO
- Shutter Speed
- Aperture
- Any exposure compensation dialed in

You can set the camera up to automate some or all of that but you still want to know where everything is set while shooting. For instance, a lot of us really like Manual with Auto ISO as it lets us set the two primary creative exposure settings (shutter speed to stop or blur action, aperture to control depth of field) and let the camera adjust ISO but when running in that mode it's really important to keep an eye on ISO to make sure it's not a lot higher than it needs to be for the situation. Same is true for other automated modes, if running in Aperture Priority mode we still want to keep an eye on shutter speed (and ISO) to make sure it's reasonable for the situation.

Bottom line is really developing a field workflow where you scan the information in the viewfinder to make sure you know where everything is set and whether it's appropriate for the shot you're trying to capture. Having tools like a real time histogram in the viewfinder can help a ton but you still want to know how the individual exposure parameters are currently set so you can make adjustments as needed when one or more aren't where you want them for the situation.

I like you idea of a workflow. That reminds me of the checklist flows in a plane, which are organized in a consistent way like, left to right, etc. Apply the same to the EVF / display so that it becomes second nature seems like the way to go. It's too easy to focus only on the image itself.

 

[bleirer]

In a sense full manual vs manual plus auto iso plus EC is almost the same thing. Either way you spin one dial and the iso is the only thing that changes. The pro to full manual is the exposure is locked when the scene or light changes unless one spins the dial. The con to full manual is the exposure is locked when the scene or light changes unless one spins a dial.