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CNC Machinist learning with medium format camera build


New member
Thanks so much, that confirms my suspicions. I did take measures to kill internal reflections as best I could, but its far from perfect. I currently have this black microfoam stuff applied to the inside walls. There are thin but noticeable gaps in different areas that I'm guessing would be enough to case the reflections. It's marketed for use inside telescope tubes. Problem is its a huge pain to work with because of how sticky the self adhesive is and how thin it is (impossible to place exactly where you want). Right now I'm considering removing the microfoam and replacing it with a coating of "Black 3.0" paint which boasts 99% light absorption.

Seeing as you were in effectively the same boat as me, what did you end up doing to kill reflections on your CNC machined adapter? I would guess that whatever worked for you will be just as fine for my application.


I actually glued a black velvet cloth in my tube. Velvet is great at absorbing light. It does however shed. I think it is more affective than paint though because I think paint generally is reflective. But I didn't know about the black 3.0 paint at the time. Would probably have been easier.


Active member
I think those bluish streaks are exposed by leaking light. It looks the light is coming at the side of the camera or the film magazine, because the film part outside the image area is also exposed. As You said it is very weak. Did You check the film magazine for leakages? There are seals that can be too old to serve perfectly.
My guess is the seal of the darkslide. The seal is made of velvet or same kind of soft material. Maybe it's worn out. When you remove the darkslide from the magazine to take a picture, it leaves a narrow opening for the light to shine in. You can check it with a flash light in a dark room.

Those "smileys" look like mechanical damages happening when developing the film. If that's the reason, signs of folding (bending?) the film are still visible in the negatives.

Btw. Reflections in the camera body can happen simultaneously with light leakages!
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