Shooting Manual With Auto ISO...A Discussion

gryphon1911

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Central Ohio, USA
Name
Andrew
My shooting habits are generally that I shoot 90% of the time in aperture priority and 10% in manual - which is generally when I am shooting with off camera lighting.

In aperture priority, I tend to use the exposure comp dial as a makeshift way of shooting "manual" with auto ISO.

I would like to hear from others who shoot manual, but with ISO set to auto. I plan on starting to shoot this way to experiment on my own, so have that covered.

It's just the more I think about it, and as good as all the digital cameras I have are in IQ between ISO 100 and 6400....it just seems to make more sense to give myself more creative freedom by having 2 exposure settings at my control instead of just 1 in aperture priority mode.

What are your thoughts regarding shooting this way? Did you previously shoot full manual with manual selection of the ISO or did you used to shoot aperture priority?

Again, just trying to get a feel for what others think about this or any stumbling blocks that might be run into while shooting this way.

I plan on starting to shoot this way today for my personal/fun shooting and see where it leads.

Much appreciation for those who choose to participate.
 
Aperture priority used to be my favorite too. However, currently I prefer shooting manual with auto ISO. As you say, cameras have become so good in handling higher ISO values that the ISO value almost does not matter. I "switched back" to aperture priority a couple of times but was not always happy with the choices of the camera so I switched back.

I also shoot fully manual, but manual S/A with auto-iso is my preference.

I used ISO6400 max with the Fuji. I've set max ISO to 12.8K on my D750 because I was amazed by the results of the camera at those levels.

The only stumble block was my mindset because I thought I could never respond quickly enough. It turns out to be fairly easy to "predict" required shutter speed and aperture.

Obviously I make mistakes but manual S/A with auto-ISO gives me more control than aperture only. I make more errors with aperture priority (eg "frozen" blades of a chopper)
 
It depends on what the camera lets you do. More and more new cameras / firmware updates allow you to shoot in Aperture priority with auto-ISO with settings for both minimum/max ISO AND minimum shutter speed. With that logic, you're really controlling both aperture and shutter speed - the camera is actually changing shutter speed as needed, but only according to the very specific instructions you give it. For example, lets say you're shooting action and want to maintain a minimum shutter speed of 1/500. You can then set the camera with a max ISO of 3200 or 6400 or whatever you're comfortable with as a maximum ISO, and a minimum shutter speed of 1/500. Then you set your aperture and shoot. The camera will maintain the lowest ISO it can while maintaining your minimum shutter speed of 1/500. In really bright light, it will maintain base ISO and will increase the shutter speed as much as needed for proper exposure. As the light decreases, it will increase the ISO as high as needed (up to your designated maximum) to maintain your minimum shutter speed. If there's too little light to maintain your minimum shutter speed even at your highest allowed ISO, ONLY THEN will the minimum shutter speed start to drop below your designated minimum shutter speed as needed. This is exactly the same logic and progression I've used when setting these parameters manually. To me, this is the best possible setup for auto-ISO except in the case where you purposely want a slow shutter speed to induce motion blur or something - at which point THEN you can easily switch to manual or shutter priority mode.

Using Manual mode with auto-ISO allows you to use the same logic but it's far more labor intensive. It's really not very different than shooting in Aperture priority with manual ISO. Shooting in either of these modes (Manual with auto ISO or Aperture priority with manual ISO) requires that you set your primary parameter (let's say it's aperture) and then adjust the secondary parameter, but while constantly monitoring the third (automatic) parameter to make sure it's within a reasonable range. In aperture priority and manual ISO, you set the ISO, but you're constantly monitoring the shutter speed to make sure it's not getting too high or low, and adjusting the ISO manually as you need to. In manual mode with auto ISO, you set the shutter speed but have to constantly monitor the ISO to make sure it's not getting too high or low, and adjusting the shutter speed as you need to.

Using Aperture Priority with auto-ISO and designating a minimum shutter speed will do the same thing, but it's balancing the second and third controls the same way you would, but doing it for you. For example, using manual mode with auto ISO on a bright day, you may not have any problem staying at base ISO in your chosen aperture, but you'd have to be raising and lowering the shutter speed if you haven't set it fast enough for conditions. With auto ISO and a minimum shutter speed, the camera will go as fast as it needs to without you having to do anything, but you know you're also protected if you or your subject is moving through shadows and it needs to drop the shutter speed to your minimum and raise the ISO somewhat. Similarly, as light gets lower, in manual with auto ISO, you'd have to constantly lower the shutter speed as needed to keep the ISO in a reasonable range. In aperture priority with auto ISO and minimum shutter speed, it'll find that balance for you at the point that maintains your minimum shutter speed with the lowest possible ISO.

So, on balance, I don't really find using manual mode with auto ISO much different in practice than shooting in aperture priority with manual ISO. Either way, you still have to set two of three parameters based on careful monitoring of the third, automatically adjusted parameter. I used to go back and forth between these two modes with my Ricoh GXR and couldn't find a difference in how I shot. If anything, I preferred aperture priority with manual ISO because shutter speeds had a much wider range of possible values to be adjusted automatically than ISO, so I was better off changing ISO as needed and letting the shutter speed float than vice versa.

The only problem with using Aperture priority with auto ISO and minimum shutter speed, as I've outlined above, is that not all cameras do it, or do it well enough. Samsung and Nikon do it incredibly well, and Sony's newest models (A7R II, RX100 IV, and RX10 II) also adopted this industry standard that Nikon and Samsung have been using, but earlier models didn't offer anything like it and Sony doesn't appear to do firmware updates. Leica's newer models have this feature. Fuji's higher end models offer this now, with the caveat that you can't set the minimum shutter speed faster than 1/500, which might not be enough for some serious action shooting. Ricoh has the same problem to an even greater degree with a fastest minimum shutter speed of 1/250. Canon offers it through an auto ISO feature they call "rate of change", but they offer far less specific control than Sony, Nikon, Fuji, or Samsung. Panasonic doesn't do it at all. Olympus doesn't either, but there's a workaround that allows you to essentially do the same thing up to a max shutter speed of 1/320. I'm not sure about Pentax or Simga.

Auto ISO has become an overwhelmingly powerful tool with today's high ISO and high DR sensors. When paired with a good shutter speed control within the auto-ISO menu, it's revolutionized how a lot of people shoot. Without that feature, however, it's just a matter of choosing your poison in terms of what you'd rather control and what you'd rather the camera controls.

-Ray
 
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Ray,

Some really good thoughts there. I know my Nikon's handle this aperture priority with auto-ISO very well, as do the newer Olympus OMD cameras. As you say, the aperture priority with auto ISO, if implemented intelligently covers the majority of situations.

I've just not really shot in manual with auto ISO and I'm attempting to broaden my horizons a bit shooting with a new way of thinking.

Again, lots of good info in there to digest from everyone.
 
Just to chip in a little...

I *think* I shoot at about the following percentages:

FULL AUTO: 10%
AP PRIORITY: 50%
AP + SHUTTER (Auto ISO): 30%
FULL MANUAL: 10%

It's something like that. I generally care about depth of field, and I also know that if I crank the aperture open, I'm going to get a lower ISO and faster shutter speed, so often that's an easy way to gently nudge the camera in those directions without having to touch a second or third control. If I'm out in daylight and I have the 35 f1.4 on, and I crank it to f2, I know I'm going to have a shutter speed around 1/4000 and an ISO around 320. I find myself going to full Manual when I'm in a room with patchy light, and I want all the shots exposed the same way.
 
Ray,

Some really good thoughts there. I know my Nikon's handle this aperture priority with auto-ISO very well, as do the newer Olympus OMD cameras.
Olympus? Really?? Are they doing it the same way as Nikon? If so, that's great news - they didn't have anything like that with the EM5 or EM1 when I had those. They had a workaround using flash sync speed that would effectively let you do the same thing up to 1/320, but no direct shutter speed control labelled as such under auto-ISO. Have they updated firmware to add that feature to existing cameras, or is it just in the really new stuff like the EM5 mkII?

In any case, nothing wrong with experimenting. I've spent plenty of time using M mode with auto-ISO and I never found any real benefit to it relative to Aperture priority with manual ISO, and never liked it nearly as much as A mode with auto-ISO and good shutter speed control. But a lot of Ricoh users seems to swear by TaV mode, which is essentially the same thing...

-Ray
 
Interesting discussion. Until recently I never used auto iso, mostly because I'm a control freak, but since getting an X-Pro 1, I use it a lot, with C1 and C2 set with different iso parameters and use of the exposure compensation dial to tweek exposure. I shoot almost exclusively manual and aperture priority, mostly out of habit, I suppose, since my first two SLR's were a manual Olympus OM-1 and an aperture priority auto OM-2. With the kind of shooting I mostly do, aperture control is more important to me than shutter speed, though as Ray said, it's nice to be able to dial in parameters within which the camera will choose shutter speed. That I could not do that with the E-M5 is perhaps why I never used auto iso. It's convenient and lets me concentrate on other things.

Once I set the camera on manual, I feel I'm taking charge of it all, so I haven't used auto iso with it, though Ray's observations seem on target to me.

In my sixties now, I feel justified in using conveniences I once spurned. It all goes back to changing my oil one day in my late 50's, being under the truck and get hunks of cholla cactus stuck in the back of my neck. I distinctly remember something like the voice of God resonating in my mind with, "You're too old for this sh-t".

Using auto iso is the photographic version of letting Jiffey Lube change the oil. Then I can concentrate on driving.
 
i shoot in aperture priority/auto iso unless i am in a situation where i must exert direct control over the shutter speed, in which case i shoot fully manual with auto iso if its available. i like to keep things simple.
 
Ray,
While I agree with what you write (great write-up, as always) the camera is not capable to assess what scene I am shooting and how stable my position is. E.g. when I made the shot of the chopper (you may recall that one) I used Aperture Priority. The camera did choose a high shutter speed, resulting in frozen blades. In addition, I've set minimum shutter speed at 1/40 for the 35mm lens. Sometimes that is too slow but sometimes (when I can rest my elbows or the camera on something) it is too fast. And that happened more frequently than I expected. So I found manual A and S more flexible, especially with the DSLRs because it's possible to change settings instantly by turning the wheels. But even with the Fuji it was easy to change shutter speed quickly. I can comment on other brands.

W.r.t. stumble blocks, I forgot to mention one thing. When you switch from good/dim light to bright light, you have to 'hardwire' the habit to increase shutter speed as ISO cannot get lower than a certain point. I forgot that a couple of times when I was in a hurry or very excited about a certain photographic opportunity.
 
Ray,
While I agree with what you write (great write-up, as always) the camera is not capable to assess what scene I am shooting and how stable my position is. E.g. when I made the shot of the chopper (you may recall that one) I used Aperture Priority. The camera did choose a high shutter speed, resulting in frozen blades. In addition, I've set minimum shutter speed at 1/40 for the 35mm lens. Sometimes that is too slow but sometimes (when I can rest my elbows or the camera on something) it is too fast. And that happened more frequently than I expected. So I found manual A and S more flexible, especially with the DSLRs because it's possible to change settings instantly by turning the wheels. But even with the Fuji it was easy to change shutter speed quickly. I can comment on other brands.

W.r.t. stumble blocks, I forgot to mention one thing. When you switch from good/dim light to bright light, you have to 'hardwire' the habit to increase shutter speed as ISO cannot get lower than a certain point. I forgot that a couple of times when I was in a hurry or very excited about a certain photographic opportunity.
I agree - the one place using auto-ISO with a minimum shutter speed in "A" mode doesn't work particularly well, and sometimes not well at all, is when you specifically want a slow shutter speed. It's doing everything in it's power to keep you from going below whatever you've set as a minimum shutter speed (and it's often faster than your minimum), so for shots where I want a slower speed for whatever reason (other than not enough light, which the camera will work out on it's own), I just quickly switch over to manual or shutter priority mode for those slower shutter speed shots.

But, honestly, I have never run into any other situation where the "A" mode with auto ISO and minimum shutter speed mode doesn't work as well or better than any other mode with a greater amount of manual control. It's good to be able to change your auto ISO setup quickly for different lenses or different types of shooting, so for that I really prefer Nikon or some other makes with convenient memory settings to store different groups of settings in. I have one setting for street shooting (pretty much always with a prime lens between 20 and 28mm - fast single shutter speed, high max ISO), one for action (presumably with a zoom - high max ISO with fast shutter speed but variable depending on focal length), one for static shooting in low light with stabilized lenses (slow shutter speed but variable based on focal length, so it works with zooms or primes), one for "normal" shooting in good light where best IQ is the goal and getting the shot not that tough ("normal" shutter speed, variable with focal length, but fairly low ISO ceiling). On my DF, I push one fn button that calls up a menu with my list of different named settings, so it's very quick work to switch between them while I'm out shooting... And, of course, switching over to manual or shutter priority for a block of shots, as needed, is also very quick...

-Ray
 
I guess I'm an outlier. I like to shoot in P and dial in some exposure compensation. I use auto iso. I think I really don't do enough portraits to get to excited about shallow DoF, so I'm mostly worried about minimum shutter speed. I know the camera (OMD) has IBIS but I also know what kind of blurriness I see when things go bad and it's always motion blur.
 
Can You explain this in more detail, pretty please?
As close as I can remember, if you were using auto-ISO in A mode, there wasn't any sort of direct shutter speed control, but if you set your flash sync speed to 1/200, that would become your minimum shutter speed, if you set it to 1/300, the same thing, etc... I remember it working about the same way as the current auto-ISO setup on Nikon, Sony, Samsung, Fuji, etc, although I don't recall how it behaved if there was too little light for that minimum shutter speed and the max ISO you've designated. And the biggest issue, for me at least, was that 1/320 was the fastest you could go with that workaround and that's just not fast enough for a lot of uses.

I don't know if any of this is still the case - I haven't owned an m43 body in well over a year now and there have been umpteen firmware updates since then. It would be great if they've actually added a direct minimum shutter speed control in their auto-ISO menu, but I don't know one way or the other...

But that's how I remember it...

-Ray
 
Olympus? Really?? Are they doing it the same way as Nikon? If so, that's great news - they didn't have anything like that with the EM5 or EM1 when I had those. They had a workaround using flash sync speed that would effectively let you do the same thing up to 1/320, but no direct shutter speed control labelled as such under auto-ISO. Have they updated firmware to add that feature to existing cameras, or is it just in the really new stuff like the EM5 mkII?

-Ray
It's not the same. My thoughts must have been on a different camera.
 
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