Yellow spots from sprocket holes on scan

Hi there,

I just started scanning my negatives myself. I’m using an Epson V600 and SilverFast for scanning.
Because I like my negatives with a black border around them, I decided to use the Lomography DigitaLIZA as a scanning mask because it lets you scan with sprocket holes.
The problem with this setup is, that I get this yellow spots from the sprocket holes in my scan. See image attached.

When I’m scanning with the Epson scanning mask, these do not appear on the scan, so I guess this is some kind of reflection issue. But I don’t want to give up on the black border. Anybody had a similar problem and managed to solve it?


I often convert my negatives without crop and “Border Buffer” set to 25%.

Sometimes, I simply put the negative on the backlight without any holders in order to exclude effects suspected to be introduced by the holder. Even though holders are usually black, they can still reflect some light that can be visible around the edges.

Thanks for your reply, but that’s not my issue. I do almost the same except, I’m keeping my border smaller and the buffer set to 5%.
My problem is, that when I keept the sprocket holes in the scan, it will put these yellow spots on my scan.

I haven’t thought it through thoroughly, but I suppose that the following happens:

Hypothesis: Exposed sprocket holes let light enter into the film substrate which serves as a (fairly leaky) waveguide that lets light (into the substrate and) exit around the sprocket holes. Said light must be blue-ish in order to invert to yellow…

Subject to be verified with a test that you could run on a piece of film that you can spare: Paint alternating sprocket holes black by inserting the tip of sharpie onto the holes so that the cut surface gets black thus eliminating or reducing stray light.

Alternative hypothesis: the Epson’s light source is considerably larger than the film’s image area, and the film is some small distance away from the scanning element.

So instead of being illuminated solely by light running perpendicular to the film, each sprocket hole is also lit by light coming at it from both sides and from the top and bottom. Some of that oblique light is making it through the sprocket holes and then angling into your scans. It’s the same as how you can see the headlights of an approaching car even if it isn’t coming directly toward you.

I don’t remember exactly what the Epson’s light source looks like, but you might see if you can mask it down to the exact film area and find out of that makes a difference.

We didn’t have this problem so much in darkroom printing because the light source was either right smack on top of the film (diffusion enlarger) or optically focused to be mostly perpendicular to the film (condenser enlarger.) Or when making contact sheets, the light source was farther away, but we kept the film squeezed tightly against the paper, so there was no room for the oblique rays to roam.

First off, I feel for you. This is an exasperating problem to try to solve. In my very early days of camera scanning I saw an issue with 6 x 9 medium format film that had me ready to throw the entire camera collection out the window and take up golf. Medium format film, 6 x 9, I would get rust colored stains radiating in from the tops and bottoms of the long sides of the frames. I was told it was stray light bouncing off the ceiling and lots of other suggestions that made sense but this one was none of those. The fix in this case was to mask the edges of the film, notwithstanding the fact that I had done this probably 30 times before without seeing this effect. Looking through my catalog I nailed it down to a batch of Portra 400 that I purchased in 2017. Two pro packs. Even though I regularly use a mask now, I scan my sprocket rocket as well as 110 films with the edges totally exposed to the backlight. No issues at all.

I totally believe that the light piping thing is real, Leslie Lazenby covered it in one of her blog posts at the FPP and that lady has forgotten more about film then I will ever know in 10 lifetimes. If she says it’s a thing, it’s a thing. Question is how big a thing. That comes down to the film base and manufacturing variation. Estar has wicked problems with it. So bad you will lose the first three exposures on a 35 mm roll of film if you don’t load in the dark. Even the non estar film bases use a weak dye to attenuate lateral transmission of light, in addition to the anti-halation dyes that turn your rinse water such a lovely shade of green or purple or whatever.

That said, this looks more like lens flare. The back light shining up through the sprocket holes is going to be way brighter than the light making it through the film itself. Lenses designed within the last 10 years or so benefit from truly excellent optical coating technology, things that didn’t exist 20 years ago.

The number one rule when scanning film with a digital camera is any light recorded by the camera that didn’t pass through the film first is going to cause you trouble. Reflections. Lens flare. Even subtle cases can make ugly results. You might try experimenting with different aperture settings to see if you can minimize flare or you might try borrowing a different macro lens to compare. Good luck. The problem can be eliminated, my Instagram account is loaded with sprocket rocket examples which would really show the sprocket marks if they were there.

well, the effect - as shown in the first post - came up while scanning with am Epson scanner. I suppose that scanner’s optics are simple things and might well be sensitive to too much light.

So, here’s what I tested in the meantime. I used a mask, which covers the sprocket holes. I do not have these yellow spots on the scan in that case. So I guess, It’s really a reflection from the Epson’s light source. Because of that, I don’t think it has something to do with my camera.

I tried some B&W film as well and scanned it with the sprocket holes an did not have any kind of spots. The film was exposed using the same camera. So far it seems to only affect color film.

What I want to try is to tape the light source so it will only lighten up the image on the 35mm film. But because the DigitaLIZA has no fix point in the scanner, it could get a little difficult.

We’ll see…

So I started doing scans with my Sony A7 and it seems it’s really an issue with the epson scan.
Also I like the quality of my Sony “scans” more, so I guess I’ll stick with that for now. Thank you for your replies.

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