Flare? you mean light leak?
Scratching?.... Clean all the surfaces the film will come in contact with using denatured alcohol. The 2 very thin rollers should be free n the tabs slightly above the film gate height... they tend to get flattened over the years.
Check the frame mask that all screws are tight and for debre that may scratch the film as well.
Another overlooked sourc of scratches is taking the film off it;s backing and loading the reels... not always the camera's fault.
thanks Paul I will try cleaning the thin rollers as well. Looking at the back it seems like they are the only possible source of the scratch - nothing else really comes in contact with the emulsion.
The scratch is consistent across many many rolls with this back, and never showed up on another back I was using, so I am confident it is the back and not user error.
The flare thing shall remain a mystery - if you're curious here is the original thread with pictures:
you mean that little pointy thing at the very corner?.. that's common for most backs.. I have the same thing in ALL my backs.. not to worry.. that's not a problem and has no fix.
In post #11 that pic has a light leak n that is either the mask screws, darkslide baffle, or foam needs replacing. Is teh foam gummy? take off the mask n check the darkslide bafflle to be sure it;s clean n not worn.. then when installing the mask again be sure to carefully snug the screws.
OH remember the image is reversed n upside down in your back (dull side to the lens) when trying to locate the leak. Orient the neg properly n the leak should be right there.