topic Re: Live view/Exp. Sim exposure changes when autofocusing, even in manual. in EOS DSLR & Mirrorless Cameras

EOS R6 Mark II Live view/Exp. Sim exposure changes when autofocusing, even in manual.

Chisato — Thu, 12 Dec 2024 15:26:58 GMT

I just bought myself a brand new Canon EOS R6 Mark II with the RF 24-105 f4-7.1 kit lens. It's been absolutely phenomenal. However, I have been experiencing a little idiosyncrasy with the EVF/LCD Exp. Sim.

Essentially, when half-pressing the shutter button to meter and lock AF in One-Shot AF, the screen will occasionally become brighter. I have read reports of something similar like occurring on various other forums. However, in those aforementioned instances, it seems like the increased brightness is only temporary to help the AF find its mark before the Exp. Sim returns to normal.

In my case, the increased brightness is constant until the shutter button is released or a picture is taken. This does not affect the final picture (as it does not reflect the increased brightness), and it makes it very hard to accurately judge the exposure before taking the picture. Even the histogram is affected, sliding slightly over to the right.

This occurs in pretty much all shooting modes including Manual. The firmware has been updated to 1.5.0. I suspect it's the exposure being temporarily adjusted to assist the autofocus but not returning to an accurate live view after. I just want to know if this is an issue that warrants fixing, if it's a common thing among Canon cameras/lenses (or maybe just this particular lens), or if it's a setting that's causing this to happen.

I managed to make a video of the increase in exposure when holding down the shutter button halfway and releasing multiple times to better illustrate what's going on. The camera is currently in Manual Mode (without Auto ISO) with Single Point AF and Evaluative Metering.

If not the AF, could something else be causing it? I don't think it's an issue with the metering either, as the metering shouldn't affect the exposure in Manual. Any and all help would be appreciated!

Re: Live view/Exp. Sim exposure changes when autofocusing, even in manual.

Waddizzle — Sun, 08 Dec 2024 16:35:07 GMT

Welcome.

I noticed that the center AF point seems to be flashing. I tried to watch your video a couple of times to try to see if the exposure was locked, or if it was changing, too. It’s too small to read anything.

I also noticed that you are shooting indoors with artificial lighting. Do you have Light Flickering Compensation enabled?

Re: Live view/Exp. Sim exposure changes when autofocusing, even in manual.

Chisato — Sun, 08 Dec 2024 17:03:54 GMT

Thank you so much for your reply! In the video, I'm half-pressing and releasing the shutter button multiple times to show off the effect. Anti-flicker shooting is off. Is there anything else I could do to help rule out any causes?

Re: Live view/Exp. Sim exposure changes when autofocusing, even in manual.

FloridaDrafter — Sun, 08 Dec 2024 18:25:21 GMT

Hello, Chisato, and welcome to the forum!

I've had the R6 II for a few years, I also have the R6, R5 and recently the R5 II. All of them do what you've described on occasion, particularly when I'm shooting in low light. Since it's only occasionally and doesn't effect the final image, I just live with it. I'll add that my experience is through the EVF, I don't use LV.

I'm not sure why they behave this way and I've tried various settings, including metering modes. I shoot primarily nature and a lot of that is under tree canopy, so it's challenging to adjust for the differing light on the fly 🙂

Newton

Re: Live view/Exp. Sim exposure changes when autofocusing, even in manual.

Waddizzle — Sun, 08 Dec 2024 18:27:39 GMT

“ I'm half-pressing and releasing the shutter button multiple times to show off the effect. ”

I believe that is normal behavior because you keep pressing and releasing the shutter. In other words, you are turning it off and on again and again.

Re: Live view/Exp. Sim exposure changes when autofocusing, even in manual.

stevet1 — Sun, 08 Dec 2024 19:55:53 GMT

I thought I had read one time that your camera uses the widest aperture it can for the focal length you have set. to aid in focusing, but your picture is actually taken with the aperture you have set.

Steve Thomas

Re: Live view/Exp. Sim exposure changes when autofocusing, even in manual.

Chisato — Mon, 09 Dec 2024 02:50:11 GMT

Yup. That's what I read too. However, it's supposed to return to the correct exposure after the AF locks on, but it doesn't on mine.

Re: Live view/Exp. Sim exposure changes when autofocusing, even in manual.

Chisato — Mon, 09 Dec 2024 02:55:12 GMT

That's definiely reassuring! As I mainly take still-life and portrait photos in an indoor setting, it gets very confusing to account for that change in brightness.

Re: Live view/Exp. Sim exposure changes when autofocusing, even in manual.

Chisato — Mon, 09 Dec 2024 02:58:18 GMT

So, it's normal for the exposure to change when half-pressing the shutter button even in manual mode?

Re: Live view/Exp. Sim exposure changes when autofocusing, even in manual.

Waddizzle — Mon, 09 Dec 2024 12:36:24 GMT

Don’t forget. Every time you press the shutter it is [not] just refocusing. It’s also re-metering, taking a new light reading, the entire scene in the field of view. If light flicker is disabled, then it can come back with a different light measurement every time you press the shutter.

Re: Live view/Exp. Sim exposure changes when autofocusing, even in manual.

FloridaDrafter — Mon, 09 Dec 2024 05:45:22 GMT

@stevet1 wrote:

I thought I had read one time that your camera uses the widest aperture it can for the focal length you have set. to aid in focusing, but your picture is actually taken with the aperture you have set.

That's true, Steve, but in my case (I'm not sure about the OP), my aperture is almost always wide open because of the low light I am sometimes forced to shoot in. In some of those low light situations, like under trees, in thick brush, and late evening, my MILC's will sometimes brighten, like the aperture has opened to focus (even though it's already wide open) but it never returns to the correct exposure simulation once I lock focus/metering. I use the RF 100-500 which at 500mm is f/7.1, so it's a dark lens to start with. As mentioned, it's not a common occurrence, but it happens enough 🙂

Newton