I've got some size 620 film negatives of star fields that I'd like to scan and make prints of. Can someone tell me where one frame ends and the next one starts, since the images appear to blend together? (I no longer have the notes of which fields. ) I've added red and yellow lines to a sample of the negatives (attached). Do either set of colored lines delineate a frame? If so, which, if not, what does?
With adequate exposure, the density built upon the negative should be visible upon examination on a light table or other light source, but with very brief exposures can be difficult. If you can scan the entire strip and look for the gaps between frames that would be my only advice. In your image it is hard to tell stars from splotches of dust.
Tried looking under bright light and magnifier for frame breaks, no luck. The circa 1958 Argus 75mm fl camera I used had a red plastic disk on the back of the camera where you lined up the paper backing on the 620 film that had the frame # on it. This paper was discarded before development of the emulsion, but I'm sure the numbers on the developed negatives themselves must somehow correlate to the frame exposed.
Looking at what you posted I would say the red line is roughly the center of the frame. One thing you could do when taking your photos would be to flash a frame(Waste it) then you would have a starting place.