topic Re: 1D X Mk II not changing exposure in bursts when in One Shot AF mode in EOS DSLR & Mirrorless Cameras

1D X Mk II not changing exposure in bursts when in One Shot AF mode

dbltapp — Thu, 17 Oct 2019 18:29:58 GMT

When I set aperture priority, AI servo, and High Speed continuous drive and shoot bursts, the shutter speed changes as the camera is pointed to differently lit subjects. Every frame is properly exposed.

However, when autofocus is changed to One Shot, and I shoot bursts of the same subjects, there is no change in shutter speed - it remains at the value it was for the first shot of the burst.

I'm guessing that shouldn't occur. It seems that exposure lock is happening in that situation.

So is that due to a setting I inadvertently set (I hope)?

Does the camera need a reset (clearing all camera settings didn't work)?

Is this a known issue?

Suggestions?

Thanks,

Michael

Re: 1D X Mk II not changing exposure in bursts when in One Shot AF mode

wq9nsc — Thu, 17 Oct 2019 18:55:36 GMT

I don't think I fully understand your situation, with one shot AF mode are you panning to the different subjects while continuing the burst? If so and you are in evaluative metering mode then the exposure is set when focus is achieved when you depress the shutter release half way and stays there for the burst. If you go to a different metering mode, it will meter at the time of exposure instead of staying locked.

Rodger

Re: 1D X Mk II not changing exposure in bursts when in One Shot AF mode

dbltapp — Thu, 17 Oct 2019 19:36:31 GMT

The canon folks tell me that each burst image should be re-metered even in one shot AF mode, and want the camera to be sent in to be fixed.

I found this in the manual:

“AE lock: Auto: Applied in One-Shot AF mode with evaluative metering when focus is achieved

Manual: With AE lock button”

What isn't clear is whether the AE lock is supposed to remain when shooting bursts. Came across this situation while burst shooting a bunch of stationary flaming matches. Usually shoot bursts in AI servo for moving subjects, but used one shot because AF didn't need to change.

Now I'm not sure if this is a problem or a feature...

Re: 1D X Mk II not changing exposure in bursts when in One Shot AF mode

wq9nsc — Thu, 17 Oct 2019 20:18:57 GMT

Take a look at the footnote on the bottom of P. 239 of the manual. Are you using evaluative metering mode?

I tried to copy and paste it here but apparently Canon has some protections applied to the PDF version of the manual making copy difficult.

Rodger

Re: 1D X Mk II not changing exposure in bursts when in One Shot AF mode

kvbarkley — Thu, 17 Oct 2019 23:21:52 GMT

I just use a screenshot.

Re: 1D X Mk II not changing exposure in bursts when in One Shot AF mode

Waddizzle — Fri, 18 Oct 2019 00:11:44 GMT

I do not use One Shot AF with Continuous Drive mode. If I am using One Shot AF, then I use Single Shot drive mode. If I am using AI Servo AF, then I always use Continuous Drive mode. I suggest that you stick with AI Servo mode to achieve what you want.

If you want the camera to lock focus on every frame in Continuous Drive mode, then set Image Priority to full tilt Focus Priority. This will force the camera to wait until it locks focus before if fires the shutter again, but because you are in AI Servo mode it will also meter for a new exposure on every frame. This behavior is identical to One Shot AF.

Focus Priority has two settings, 1st Image and 2nd Image. The 1st Image Priority setting sets the behavior for the first frame in a burst of frame captures. The 2nd Image Priority setting sets the behavior for all of the subsequent frames after the first frame.

I normally set both 1st and 2nd Image Priority settings to full focus priority. At the opposite end of the scale is shutter priority, which does not wait for a focus lock. Using shutter priority yields the fastest frame rates. But, what is the point of high frame rates when the images are OOF? I would rather have a burst of frames that are in focus, instead of near focus.

Besides, Canon's super telephoto L lenses can focus so quickly that any hit you might take in your frame rate is well worth the uptick in your keeper rate.

Some people may want to set the 1st Image Priority to Shutter Priority, which causes the camera to "jump start" itself into Continuous Drive. I have found this approach to be highly effective when I pre-focus on an area where I know the action will be taking place. By the time the cameras hits the 2nd Frame, it has locked onto a subject and tracks it.

Of course, if you are using only one AF point, then you will only have focus tracking at the one AF point that you have selected. If you enable multiple AF points, then the Case Settings become meaningful, and the Image Priority settings take on a greater significance on your final results.

Re: 1D X Mk II not changing exposure in bursts when in One Shot AF mode

ebiggs1 — Fri, 18 Oct 2019 15:56:52 GMT

If I understand your situation correctly I think it is working normally.

"when autofocus is changed to One Shot", is doing what it does. If you are in doubt reset it and try again.

Re: 1D X Mk II not changing exposure in bursts when in One Shot AF mode

Waddizzle — Fri, 18 Oct 2019 17:51:49 GMT

@ebiggs1 wrote:
If I understand your situation correctly I think it is working normally.

"when autofocus is changed to One Shot", is doing what it does. If you are in doubt reset it and try again.

It is operating "correctly." The problem is that behavior is not the desired behavior.

When you are in One Shot Mode, the exposure will stay locked in until you fully release the shutter. In Continuous Drive Mode, One Shot AF will refocus each shot but not meter each shot. Metering is locked until you release the Shutter Button.

If you use AI Servo, with Image Priority set to full Focus Priority, then the camera will both refocus and remeter the scene, which is the desired behavior.

Re: 1D X Mk II not changing exposure in bursts when in One Shot AF mode

dbltapp — Fri, 18 Oct 2019 19:39:03 GMT

I sort of think the same way. Yet the canon techs tell me otherwise. Recently asked them if they'd actually tried to replicate my issue with a real camera rather than just assuming how it's supposed to function. We'll see...

Re: 1D X Mk II not changing exposure in bursts when in One Shot AF mode

kvbarkley — Fri, 18 Oct 2019 19:48:04 GMT

Usually when on the phone they do.

Re: 1D X Mk II not changing exposure in bursts when in One Shot AF mode

ebiggs1 — Fri, 18 Oct 2019 20:10:21 GMT

"Yet the canon techs tell me otherwise."

Did they say how you used it was not how it was supposed to work because I think it is working as it should. If you need it to do something else you need to change some settings.

Re: 1D X Mk II not changing exposure in bursts when in One Shot AF mode

dbltapp — Fri, 18 Oct 2019 22:05:34 GMT

It does what I need it to do by using AI servo instead of One Shot. The issue about it re-metering in burst mode is sort of just academic.

Re: 1D X Mk II not changing exposure in bursts when in One Shot AF mode

Waddizzle — Sat, 19 Oct 2019 05:57:09 GMT

@dbltapp wrote:
I sort of think the same way. Yet the canon techs tell me otherwise. Recently asked them if they'd actually tried to replicate my issue with a real camera rather than just assuming how it's supposed to function. We'll see...

Sometimes techs can be wrong. They're human.

After some searching, I have found the documentation that confirms the behavior that I described. Which was, in One Shot mode the exposure will lock, and stay locked until you release the shutter. In other words, when you use One Shot, the exposure will stay locked for as long as you keep the shutter fully pressed in Continuous Drive mode.

This behavior is described in the blue box at the bottom of the page.

You can learn something every day. Apparently, the exposure lock behavior is dependent upon your metering mode. If you use Evaluative Metering, which I do 99.999% of the time for action photography, then exposure will lock once you perform the initial [focus] lock.

For the other metering modes, [apparently] the exposure does not lock. The camera will meter the exposure for each new frame when you are using Continuous Drive mode. You can learn something new every day.

If you want do not want an exposure lock with Evaluative Metering when you are using One Shot AF with Continuous Drive mode, then follow the approach that I suggested above. Even though the AF mode is AI Servo, you can force the camera to wait until it achieves a focus lock before firing the shutter, just like One Shot AF. But, it meters each [new] frame because it is in AI Servo mode, unlike One Shot AF.

Re: 1D X Mk II not changing exposure in bursts when in One Shot AF mode

Waddizzle — Fri, 18 Oct 2019 22:42:31 GMT

@kvbarkley wrote:
Usually when on the phone they do.

You're probably correct. I have had to only call in once, and they quickly gave me a Case number. I have tested this behavior before. But I never realized that it could be Metering Mode dependent.

It is not a strenuous test to figure out, but you have to recognize what to test for. You have to recognize the boundary conditions of the problem, and work from there. Most people tend test a solution, instead of measuring the problem.

Re: 1D X Mk II not changing exposure in bursts when in One Shot AF mode

dbltapp — Sat, 19 Oct 2019 14:15:46 GMT

You seem to have the winning solution!

CanonCommunity one, canon techs zero.

Thanks,

Michael

CASE CLOSED