Canon R7 wi/RF 100-500 keeps changing shutter speed while in Manual

[mikellherrick]

I've been noticing that while shooting (often in low light) my R7 will automatically change my shutter speed to 1/125 even though I have manually selected 1/400 typically. ISO is always on Auto and aperture at widest allowed for conditions.  Is that normal?  Is it because the camera thinks I can't get a good shot shooting that fast?  If I move my frame around a bit...or reset the manual speed back to 1/400...it will usually allow me to use that speed.  It is annoying because I'm also shooting in continuous mode (mechanical) and find I'm getting overexposed or blurred images when this happens. 

[mikellherrick]

It was already set to OFF...so I will try setting it to ISO to see if that works.  I might be confused about the reference to new aperture though...I don't change my aperture...and it doesn't change while I'm shooting.  It's my shutter speed that changes...and always to 1/125th...no matter what speed I manually select.  So far none of the suggestions have helped...I'm still experiencing this ...occasionally. 

[Waddizzle]

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@mikellherrick wrote:

It was already set to OFF...so I will try setting it to ISO to see if that works.  I might be confused about the reference to new aperture though...I don't change my aperture...and it doesn't change while I'm shooting.  It's my shutter speed that changes...and always to 1/125th...no matter what speed I manually select.  So far none of the suggestions have helped...I'm still experiencing this ...occasionally. 

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Are you using a flash?

[mikellherrick]

No...I don't use a flash.

[p4pictures]

This is a bit of a long shot but do you have one of the camera buttons configured to override the selected shutter speed? This can be done by Register / recall shooting functions to a custom button. The register / recall shooting functions setting allows your choice of predetermined settings to be applied while the button to which it is assigned is pressed. 

I use this myself, assigning the AF-ON button with the recall/register shooting functions on my cameras when shooting motorsports to switch my shutter speed from whatever I'm using to a slower speed like 1/125 or 1/80 for panning with a competitor instead of freezing the action.

[mikellherrick]

I haven't configured any of the camera buttons. I believe they are all set to the original settings because I haven't tried to use any custom configurations. 

[Waddizzle]

I suggest that you reset the camera to its’ factory defaults.  Reset the Custom Controls menu, too. Remove any accessories, except for a mount adapter.  Do not use remote shooting control.

[mikellherrick]

I've been considering whether or not to do this as I can't remember all the tweaks and setting changes I may have made since I got this camera to get it to the place I am happy with for the type of shooting I do.  It seems like a last-ditch solution.  However, I may have to try this after my experience today.  I had all manual settings - 1/1000 speed, auto ISO and 7.1f aperture...aimed at a flock of birds perched in bright sun.  When they took flight, I quickly followed and used my usual auto focus to zoom in and began, in continuous mode, shooting the flying flock against a bright sky...without making any setting adjustments.  The camera changed my speed to 1/125th AGAIN!  I was left with a series of terribly overexposed and blurry images.  I stopped shooting and readjusted focus when the flock came into view again...and was able to continue shooting at 1/1000th without any problem.  It's just so random and inexplicable...and frustrating.  Desperation might make me reset everything to factory defaults and start over. 

[p4pictures]

Before a reset, it's a painful step, but take a snap on your phone of every menu you can find, and if there's a menu that has submenus go down them too.

Then write to Canon and ask them to add the ability to save the camera configuration to a card like they did for EOS R5. I've already asked them to do this for EOS R6 Mark II, EOS 7D Mark II, EOS 5D Mark IV and EOS R6 over the last few years. It's simply crazy that we have cameras with so many options and settings that there's no way to back them up.

[mikellherrick]

I was on the verge of a reset...and I did take a picture of some of the settings menus already...I knew that would be helpful...but I haven't pulled the trigger yet.  I updated firmware because I was behind a couple of versions...thought that might help...but not likely.  I'm sure I'm just going to reset when I have a bit of time to do all the adjustments.  Right now it's a minor annoyance but I can't let it continue.  We'll see if a reset does the trick. 

[Waddizzle]

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@mikellherrick wrote:

I was on the verge of a reset...and I did take a picture of some of the settings menus already...I knew that would be helpful...but I haven't pulled the trigger yet.  I updated firmware because I was behind a couple of versions...thought that might help...but not likely.  I'm sure I'm just going to reset when I have a bit of time to do all the adjustments.  Right now it's a minor annoyance but I can't let it continue.  We'll see if a reset does the trick. 

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Save your current settings as a custom shooting mode.