Colour shift within film frame?

[disco2000]

Hello

I just got some a roll of film back shot with my Yashica 35GX and I found that many of the frames have this weird colour shift happening about a third of the way in from the left side of the fram.


It doesn't seem to be happening in every frame, but when it does it's always in the same spot. I wasn't sure if this is a camera issue or a film/developing issue.. Any ideas?

 

[Photo_Smith]

Because the colour differences are in the exact same place I'd probably rule processing inconstancies out because they're rarely that consistent.
That said how do the negs look? is there a density or colour difference within the frame or does it go over the edges?
My guess it is within the frame and that you have a horizontal running shutter like a Canon.
If that is the case then possibly the shutter is sticking at some point during exposure the more cyan parts of the frame are the ones that are denser. By the look the two shots above were shot at 1/60-125 if you shoot at 1/1000sec the band may be smaller.
You may have different springs for lower speeds on some shutter types, I say shutter.
Open the back next time you have no film in the camera see if it sticks.