Dark vignette appearing on one side of pics taken with Canon R6 when using studio strobes

[Radison]

I'm having a problem with vignette/banding on one side of my pics when using studio strobes. At first I thought this might be caused by exceeding the shutter speed max resulting in banding from the curtain but the attached samples were all shot at 1/160 which is well within the 1/250 max for my Canon R6 when using studio strobes (Alien Bees). These were shot at 100ISO, 58mm, f6.3 using my Canon 24-70 f2.8 L lens. The strobes are set up either side of me at the same distance on the same power level

This seems to keep happening when I do studio shoots and I would really appreciate any thoughts on how to fix the issue. Thanks a lot!

Vignette is at the bottomVignette is on the leftVignette is on the left

[ebiggs1]

First thought is placement of the strobes. You may have to move one or both to balance the scene. Your back drop may not be perpendicular to the camera so check that.

[ebiggs1]

Do and check the easy stuff first!  😊

[Radison]

Thanks so much for your input EB. I really appreciate it. It's a great point but this has occurred on all my recent studio shoots and the band is always on the left when shooting portrait and then at the bottom when shooting landscape. This is despite having the strobes set up the same way and distance either side of me with the same power and the backdrop perpendicular. So I don't think the strobe balancing or perpendicular backdrop are the issue in this case. Do you have any other suggestions I can explore?

[ebiggs1]

I know of no issues with inconsistent output from Alien Bee strobes but it is a possibility too I guess. Even though you have them spaced exact distance, BG right, try altering that distance to see if it either clears up or gets worse. If it improves or gets worse it could be a faulty strobe. Cameras tend to capture exactly what we tell them to, ... mostly!

I suppose so we need to eliminate the camera being at fault, you need to have Canon do a C&C on it. At the same time explain exactly what you are seeing.

This can be corrected in Lightroom or Photoshop.

[ebiggs1]

However, ...

As you can see it is an easy fix in Photoshop.

[Waddizzle]

Light flicker?  How much ambient lighting is in the photos?  But, it is weird that it always seems to be in the same place, though.

[ebiggs1]

"... it is weird that it always seems to be in the same place, though."

I gave that some thought, too. I am still leaning to the BG not being exactly perpendicular (or flat) to the camera. As you can notice in the last example the bottom edge of the BG isn't straight. It doesn't take much to cause a slight difference in lighting. The vignette is slight anyway so a simple task to correct in PS.

[Radison]

Yes, that would be a good point about the strobes. What makes me think that's probably not the culprit for my issue is that it has occurred at different studios with different strobes. It seems like I might need to get the camera checked out. I do really appreciate you taking time to address my issue.

[Radison]

Yes, I think that's a good workaround until I resolve the cause. Did you use the linear gradient feature on the section with the vignette and reduce the shadow?? Would love to know a quick photoshop fix. Thanks!