Interesting article on Auto ISO setup

See https://fstoppers.com …ing-448692#comment-thread

One, Ian is unable to make 12800 work for detailed images which I find suspect.

Two, I don't see anywhere that Ian checked his safety shift value, which may also be an ingredient there.

He may teach photography but doesn't know technology, how to research Canon articles, or maybe even how to truly use his gear, IMO, but rather just the basic items.

We get other articles on fstoppers that like auto ISO but again I don't care too much for their articles.
https://fstoppers.com …ange-way-you-shoot-368384

We also have Canon explaining this but again Ian doesn't bother doing the research?
https://support.usa.ca​non.com …page=content&id​=ART136820

At least most of the people in the comments seem to know how it works.

After all, he's using Av mode, which implies I set the aperture, the camera modifies the time until exposure is correct. Which is exactly what it does.

What this person seems to fail to understand is that the setting he has found, maximum exposure time, is related to Auto ISO, and Auto ISO only. It's just the limit you set for when the camera stops extending the time, and instead starts increasing the ISO, when it gets darker.
Once you run out of ISO settings (and the camera does respect your setting there), it will return to increasing the time.

Safety shift for Av will only give an effect if you also run out of time settings. That is, if the max ISO you allowed, combined with 30 seconds, still isn't enough for your selected aperture, then it will start opening the aperture too, if there are more stops available. Otherwise, it will indicate underexposure and the images will be darker.

Safety shift can be set to ISO as well, and this would presumably stop the shutter time shift that Ian is seeing. If Ian has read the manual or researched Canon online documentation, he would have seen that the camera will operate the best it can in auto-ISO given the constraints to control it, but at some point the camera takes over and tries to change what it can to still get a shot.

I am not sure what Ian is shooting, even as a test, but in real life either he will get a grossly underexposed shot with his parameters or he will get a very blurry image, in either case, nothing is salvageable. There are healthy expectations with gear and the firmware, and then there are taking things really to the extremes to punch holes in the camera execution.

LOL at the Sony people that say "mine works that way, it won't go below minimum shutter", but then they never say what happens to their images when they restrict the camera that way, and Canon's implementation "wants" to try to at least get the shot for you.

I only use auto ISO in M. This way I control the aperture and minimum shutter, and let ISO float along with EC that I set. I cannot remember the last time I used Tv or Av modes to think of it. I am sure it is useful in Tv and Av modes, but quite frankly, I feel that I would have a hard time watching two values try to fluctuate to compensate for the scene, and decided a long time ago to manage 2 of the 3, and leave the 3rd to the camera. It works so very well this way, I rarely have a missed exposure by over 1 stop, and those that are within one stop are due to my metering mode selection, I feel.

I set up and similarly shoot with auto ISO in AV mode. it works very well

I set ISO parameters in camera and let it land where it wants to land. 12800 is very clean on the 5D4 and 1Dx2. So everything stops at 12800 in my settings

I guess I need to check, but I'd bet he has safety shift on. But then you do have to question the whole autoISO in Av thing.

I too have only used autoISO in M.

So if you set a min SS with safety shift off, does it still go below that min SS?

I mainly use manual ISO, but do set to auto when I know I'm in situations with quickly changing light situations. I don't find issues with auto ISO and Av: I'm used to looking at settings in the viewfinder. No matter what settings the camera choses, I still look at aperture, shutter, and ISO when I'm metering....not really sure why the author is surprised that he insists on a lower ISO limit and set aperture....that the shutter will have to get slower for 0EV.

One of the comments mentioned a car analogy along the lines of imagine if you had an automatic car and you manually selected 3rd but instead, the car decided to use 4th.

Well, that's exactly the way my car operates. If the engine revs are too high the car won't go into that gear, likewise, if you've manually selected 2nd and the car slows too much it will automatically drop down to 1st.

The manufacturer has built in overrides to ensure the car still operates effectively.

If you want to push the drive train, go manual.