Canon R5, light leakage? Brighter exposure on the edge of my photos

[bolofoto]

There seems to be a bright overexposure running along one edge of my photos, seems to be the bottom of the censor maybe. Anyone else experience this? I am using a Canon EF adaptor and a Sigma 35mm lens. 

[bolofoto]

I was using HSS flash. This is not a high speed sync flash issue. That image stripe on the edge is there whether its 1/300 or 1/800 which were most of my shots. The sync issue would be MUCH more prononced and in different location based on shutter speed.

Also, as I mentioned, its not there in mechanical shutter. 

[Waddizzle]

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@bolofoto wrote:

I was using HSS flash. This is not a high speed sync flash issue. That image stripe on the edge is there whether its 1/300 or 1/800 which were most of my shots. The sync issue would be MUCH more prononced and in different location based on shutter speed.

Also, as I mentioned, its not there in mechanical shutter. 

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Exactly.  Use the mechanical shutter.  What's the point of using salient shutter with flashes and strobes popping off?

[shawnphoto]

I have seen this before with the EOS R. Why it happened I never figured out, but randomly some images would have an oddly bright edge similar to this, always on the right/bottom edge. Haven't noticed it on the R5. It could be lens related, you never know. I would try a Canon lens if you have one.