Canon R5 Expo. Simulation issue


Travel Guide
20 Nov 2023
Image Editing
The R5 manual is terse and not very helpful about the settings for Exposure Simulation (Red 7). The choices are Enable/During/Disable. When to use which?

When shooting with flash and Expo. Simulation set to Enable, the viewfinder functions fine but irritatingly blacks out a second or two after an exposure, often right when you want to take another shot.

Going to During or Disable eliminates that problem. Is that the right solution when using flash?

I think there are some manual off-camera flash units that present a black viewfinder unless the setting is a particular one - but I don't know which, and the manual doesn't say.

I can't find explanations on the Web on how to use these settings. Does anyone know?
From what I understand, when Exposure Simulation = Enable, if shooting with a fill-in flash, then the R5 only previews the ambient part of the exposure and not the combined Ambient/Flash.

I just fitted a Canon Speedlite EL-1 in the hot shoe of the R5 with an RF 100mm F2.8L and with Exposure Simulation = Enable, I only experienced a sub-second fleeting blackout, very similar to what the Reflex Mirror flip-up looks like in a DSLR.

The EL-1 also kept up with Low Speed Continuous during a burst and again, no blackout. just the sub-second fleeting blackout, very similar to what the Reflex Mirror flip-up looks like in a DSLR. I was in Mechanical Shutter Mode.

The behaviour might be different with a non-Canon flash?

Nina Bailey writes:
"When shooting with a dedicated Canon Speedlite, it appears that the system automatically detects the flash is being used and switches to showing you a good view of the subject rather than previewing the exposure, even if exposure simulation is left enabled."

Not sure if that helps?

I have this issue as well. The way I understand it, the camera can't simulate the exposure correctly when using flash. As Dennis wrote, the camera only previews the ambient part, so when shooting macro, the viewfinder usually goes (nearly) black.
I simply turn off exposure simulation when shooting macro, where the flash is usually the main light source.
I use a Canon flash, and have the darkness issue. I just turn it off for indoor flash photography. I have it saved to one of my custom settings (C3). Most of my shooting is outdoors, so the default is on.
Thanks for the posts. They make sense.

I did some tests and some reading and now think I have a (shaky) understanding of how it works.

It's pretty obvious that exposure simulation is supposed to show the exposure that the camera will capture, if there is no flash.

With flash it gets a lot more complicated. The camera can't or doesn't want to calculate the flash exposure. With ExpSim set to Enable, my R5 shows a "Standard" brightness in the viewfinder. It is a nice brightness for composing but does not reflect the flash setting at all. This Standard brightness is on for only 8 sec or so. After that it goes to simulation. A half-press of the shutter button gets it back to a Standard mode.

After taking the pic, the viewfinder has a Standard brightness for 2 sec, after which it goes to a simulated viewfinder. It might look like a blackout, but it is a simulated view (usually dark) of what the sensor is seeing now. Focus is lost. A half-press of the shutter button gets everything working again, but it has cost me a couple seconds.

It is best to go into the menu and set ExpSim to Disable when using flash. The viewfinder then always shows the view in Standard brightness. There is no image review after the shot.

My R7 works about the same except Exposure Simulation is called Display Simulation, and the Disable option is not visible in the menu unless you scroll down.
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It is best to go into the menu and set ExpSim to Disable when using flash. The viewfinder then always shows the view in Standard brightness.
That's what I do and I've added disabling exposure simulation to the MyMenu so I can access it quickly. I wish they would allow configuring a button for it.

I guess the camera just cannot know how a flash will be used (direct, bounced, diffusors, etc.). I do agree that the viewfinder showing a standard brightness and then going dark after a couple of seconds is annoying. They could have made it dark right from the start and just shown an icon indicating that exposure simulation is on and a flash is on the camera.
I just checked my R5 and found that I have “Viewfinder review” set to “Disable” so I don’t have the image review popping up when shooting.

Shoot menu - Shoot 7
Image Review
In the “Image review” menu there are two options.
“Review Duration” and “Viewfinder review”.

The default for the “Viewfinder review” is “Disable”, which means that when shooting continuous sequences, the image review does not display when shooting.

My mistake - after the exposure, the VF does not show the image but goes to 2 sec of Standard view. (Fixed my earlier post.)
On my R5-600EX combo I get blackout if I turn the flash off or if flash recycle time is slow, ie flash is not ready to go off. At those moments the camera shows the set exposure without flash. When the flash is able it shows the(expected) exposure with flash.
The camera can never preview the flash exposure, as it has no way of knowing how the light from the flash will hit the subject prior to actually firing the flash.
If it brightens the scene that's just to a level where you can see it. Flash exposure may be different.

I did a test today, when I had the flash on the R3. Indeed there's no difference in the viewfinder's preview regardless of whether the flash exposure is set to neutral, -3 or +3. As expected.
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