Why does my EOS R5 keep going to auto ISO?

[comolfa2]

Can you help me? I have done some shoots recently with my R5 (with battery grip) in Manual mode and the Lock button engaged. I am using a Godox transmitter for lighting. However, it keeps jumping into Auto ISO. What am I doing wrong https://100001.onl/ ?

[jerry4422cherry]

let’s address the issue with your Canon EOS R5 jumping into Auto ISO even when you’re in Manual mode. Here are a few things to check:

Lock Button: You mentioned that you’re shooting in Manual mode with the Lock button engaged. The Lock button on the EOS R5 is located just to the right and above the mode button. If it’s accidentally engaged, it might prevent you from changing shooting modes or other settings. Make sure the Lock button is not active.
Custom Functions Settings: Sometimes, AARP® Official Site certain custom settings can affect how your camera behaves. Check if you’ve accidentally set any custom functions related to ISO or exposure. Navigate to the Custom Functions menu and review the options there.
Godox Transmitter Compatibility: While Godox products are popular for off-camera lighting, there have been reports of compatibility issues with Canon cameras. Some users have experienced problems with Godox triggers causing the camera to revert to Auto ISO or change flash modes unexpectedly. Ensure that your Godox transmitter is updated to the latest firmware. If possible, try using a different Godox trigger or test with another compatible flash unit to see if the issue persists.
Auto ISO Limit: You mentioned that you’re aware of setting a limit to your Auto ISO. While this is a workaround, it’s good to know that you can manually set an upper limit for Auto ISO in the camera settings. However, it’s understandable that you’d prefer not to rely on this workaround

[shadowsports]

Greetings ,

Under your custom functions menu settings, please look at Safety Shift.

[johnrmoyer]

I hope some of this might be helpful.

There are several places in the camera menus that might cause the ISO setting to change automatically.

https://cam.start.canon/en/C003/manual/html/UG-03_Shooting-1_0070.html#Shooting-1_0070_2 

Note

• The [Minimum] and [Maximum] settings will also function as the minimum and maximum speeds for ISO speed safety shift ().

https://cam.start.canon/en/C003/manual/html/UG-03_Shooting-1_0070.html#Shooting-1_0070_2 

https://cam.start.canon/en/C003/manual/html/UG-08_Custom_0030.html#Custom_0030_1-7

Note

• Safety shift overrides any changes to [ISO speed range] or [Min. shutter spd.] from default settings in [ :  ISO speed settings] if standard exposure cannot be obtained.
• The minimum and maximum limits for the safety shift with the ISO speed are determined by [Auto range] (). However, if the manually set ISO speed exceeds the [Auto range], the safety shift will take effect up or down to the manually set ISO speed.
• Safety shift will take effect as necessary even when flash is used.

Auto lighting optimizer enabled might cause the ISO to change.

Having a flash attached changes some of the behaviors. I do not use a flash often, so others could give a better answer.

I use Fv more than M, and some of the behaviors differ between the 2 modes even when none of the settings are auto in Fv mode.

Some of the interactions among camera settings have changed with firmware updates. The version of firmware in your camera might matter.