Exposure Automation - A Rant

Well maybe not a rant. How about a calm cool collected analysis of your typical garden variety evaluative smart meter. You know the kind. They're built into every camera in existence now. They're infallible according to camera reviewers worldwide. Yet somehow they get more infallible with every new camera release.

The metering is so so so accurate in this camera it nails the exposure on every shot. Paraphased generic camera reviewer

I stopped believing this manure way over a decade ago but being the curious type I always do a bit of due diligence on new cameras. Most of the time not right out of the gate but every once in a while when it crosses my mind. Fueled again by an internet conversation on working method and proximity to a set of images I haven't seen in a few months I thought I would attempt a lucid set of guidelines for deciding on your own working method illustrated with a few examples from my Fuji X100S.

You may recall my first road trip to DC was to fiddle with things I usually don't do. One of which was really seeing how I worked with a 35mm FOV given no preconceived notions by getting my go-to 50mm shots out of the way, then shooting the same scene with the 35mm. I am over that. Another thing I mentioned that I fooled with was this allegedly superior auto exposure working method that all the reviewers and new kids somehow believe us faster at what we do. Hey – how can I lay claims to one way of working over another if I don't actually attempt the other way?

Let's layout a typical scenario. At least what I believe is typical:

  • Identify a subject.
  • Set up shot including exposure.
  • Check results - as in chimp.
  • Adjust if required.
  • Work the scene and the subject for variations.
  • Move on to next subject or next scene.

The assumption here is for most work with some sort of intent, there will be more than a single shot of that subject in any given scene. Judging from other people that I have seen I am most likely on the low end of the number of shots per scene rather than the high end. I still shoot more than one. In a lot of cases I shoot a dozen. For the vast majority of your shooting do you only shoot one shot? I am talking about making photographs with intent rather than random camera fiddling. Let's assume you do - if not don't bother reading further.

Okay so let's look at my preferred way of working. Eighty to ninety percent of the time I shoot in manual exposure mode. I take a camera reading in one of 8 different ways depending on my mood or the the way the scene looks or a combination of both. Doesn't really matter how I get my starting point - if shooting strobes I guess. I check it on the back of the camera. Adjust. Check again and then rock and roll until I change the scene or the subject or the lighting. Let's call this set it and forget it mode. During that first DC road trip I decided to use aperture priority auto and evaluative metering and contradict it with exposure comp which seems to be a very popular way of working because it's so so so much faster.

Let's take a look at an extremely small subset of results. Just a few shots. Starting with the one at the top. Same as the test shot I chimped immediately before this. I was surprised truth be told. I expected it to be 2/3 to 1 stop under exposed. Okay let's go. Here the next shot…

Again surprising it's the same and the same as I would have locked in manually. How about the next one…

Okay it changed a hair – I am good with that – NBD. Then again what caused this? That tiny bit of dark on the right? The idiotically small variation in framing? Why darker? That makes no sense. Okay what about the next one?

Here we go – same ol' same ol'. Now we have too dark. WTF? Let me get this strait. If we have no tiny bit of dark on the edge the exposure is fine. If we add a tiny bit then it gets darker but if we have less tiny bit but not none it gets darker still? How about if we add more darker stuff to that right edge?

What? Still dark? I defy you to tell me why we have exposure variance here? I defy Fuji to tell me specifically. Is it mind blowingly bad? No. Is it annoying and inconsistent and could make or break you. Maybe. I have seen variances that are far larger than this with the same idiotically small changes in framing. Do you really really think you can predict those variances or get to know what your evaluative meter will do with certainty? No way. I have seen it properly expose scenes that are mostly white all the way to gross under exposure of a very similar white scene.

So where does that leave you? Chimp every shot to see? What then – argue with the meter via exposure compensation and check again? Wash rinse repeat? Oh yea that really helps us focus on the subject and is so much quicker than just shooting with a locked in set of values. Not in my book. Exposure lock is the answer you say? Locked to what? Lock it before you chimp? Lock it after you chimp and dial in some compensation? Well how do you know what it was compared to now? Oh I see remember it and only lock it in if it agrees with what it was plus your adjustment. Lock it in and add comp later? Got-ya - some cameras are quirky and AE lock literally locks out the compensation adjustments too. Even if the camera doesn't when does that AE lock turn itself off? Varies by camera. Some will turn themselves off when the meter times out, some when you hit the play back button, etc. I just don't see how it saves any time…

Oh I get it. I missed the fact that you could pay attention to the shutter speed/aperture thing in the viewfinder and dial in comp so it always matches what it "should be". Really - how about a better idea. Pay attention to your subject and the light instead and just set it for what it should be until something actually changes. There's shitloads of stuff to pay attention to already. You really really want to play games matching up exposure shot to shot via compensation and paying attention to the numbers in the viewfinder instead of just set it and forget it?

Okay there was a tiny bit of a rant. I hope this illustrates choices that you can make in your working method. There is not a one size fits all. Sure there are situations where you are chasing a subject around and the exposure changes every shot where it might be better to hope and pray on auto exposure. I do that for sure but I have no idea why you would do that if the scene and subject and lighting are not changing shot to shot. I also finally got around to illustrating what I am talking about when I claim that every single camera I have ever used will randomly change exposure based on minisule framing variations when using intelligent metering on auto exposure.


Ps. Killing two birds with one stone, these are JPEG's SOOC from the X100S for the guy that asked what my JPEG's look like. Not my best work but fine for illustrative purposes.

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