Orange bleed at edges of scans! Need help!

@Digitizer I’ll try that and report back. Thanks for the suggestion.
I did try taking a shot of a blank strip of negative. I didn’t notice any vignetting or uneven backlighting of the lightpad.

@runswithsizzers

A. Yeah, I taped over the rest of the lightpad with black electrical tape, only leaving a window big enough for the negative.

B. I work in a mostly dark room. There’s a small amount of ambient light that seeps through between the black-out curtains I have on my window. I can’t imagine it’s enough to cause a reflection though.

I wonder if the lightpad is giving off enough light to illuminate objects around my desk (maybe even my shirt?) in turn causing reflections.
I was thinking about creating some sort of tube or box with non-reflective material to place between the negative and the lens… Good idea or bad idea?

I know it’s not a light leak in my camera as I had the same roll scanned by a lab for comparison.

When working in a room with windows during the daytime, I use an empty oatmeal box painted flat black inside to shield the negative and lens, but in a darkened room I don’t think it’s necessary.

Considering you have eliminated other sources of light and reflections - and further supported by the fact that moving the camera away from the negative seems to help - makes me suspect the camera or lens itself may be causing a reflection (?)

Is there any chrome trim on the front of the camera or lens?

I assume you would not have a “UV” filter on the front of your lens for this application, but if so, that would be a flat surface that might reflect light back down on the negative.

This might be the second step. My first step is to take your camera including lens, adapters etc. and point it at a white wall that is evenly light by daylight. Make sure you don’t cast a shadow, however faint… If this leaves no vignetting, the source might be the remaining setup - or the originals themselves. What does your lab scan give you?

I have the same problem.

My setup:

  • Sony a7r3
  • Tokina 100 2.8 AT-X Pro D Nikon
  • K&F Adapter (Nikon - Nex)
  • Skier Copy Stand / Box



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I also tried photographing negatives in different rooms, but got the same result every time.

This is the result of uneven light distribution across the negative. You can manually improve the results working with the Vignetting sliders under the Lens Corrections panel in Lightroom, but the best results are obtined using Flat Field Correction which is fairly easy to implement as part of the digitizing process. I posted some analysis on my blog.
https://www.cuchara.photography/blog/2019/5/better-negative-scans-using-flat-field-correction-in-lightroom

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Ok, I’ll give that a try. Process of elimination!

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Wow this is the first I’m hearing of Flat Field Correction. Seems like a good option if it’s not possible to get even lighting/exposure otherwise. Your blog post is very informative! I’ll try this today and see how it goes. Thanks!

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Thank you! I will try it too!

As I understand it, the negative carrier must be exactly the size of the negative itself, then the extra light from the lightpad will not illuminate the frame. With Skier negative holders I can easily cover empty areas of light for 6x7, 6x8 & 6x9 films, but with a 6x6 frame size, it is not possible because the two parts of the negative holder rest on each other.

I’ve been trying to get similar effects like you do, but did not get them. I was shooting in a daylight room (no direct sunlight) in a corner besides a window. Backlight was a Kaiser device and exposure was 0.5s, f/8 at 100 ISO, 120 film fixed in a lomo digitaliza device. Ambient light was >5 stops below exposure.

Empty areas do matter for white balance, but did not seem to have further influence.

Hmm weird. That sounds like my setup minus the day-lit room (and I’m using an artograph lightpad). Are you using a modern macro lens?

I took a few shots of a white surface lit by daylight like you suggested. I bumped up the contrast and lowered the exposure in LR. Seems like there’s some pretty noticeable vignetting. Results below –



Could it all be due to this lens?

I played around with vignette correction / Flat Field Correction like @jnstovall suggested and they’re creative solutions but ideally I’d like a clean scan/shot straight from the camera.

Used a Canon EF 100 f/2.8 USM Macro lens on an EOS 5D Mark III for these tests. Check these for tech data:
https://www.dxomark.com/Lenses/Canon/EF100mm-f-2.8-USM-Macro-mounted-on-Canon-EOS-5D-Mark-III---Measurements__795
https://www.opticallimits.com/canon_eos_ff/489-canon_100_28_5d?start=1

I set aperture at f/8 for a tad less vignetting. For sharpness, f/5.6 would have been better, I’ll have to try this for depth of field though.

Using this lens on my EOS M6 will remove all vignetting - but increase noise. Another decision/compromise.

The shots show a pattern each that might be your object’s rather than your lens’s. If the pattern were caused by the lens, you’d have to stick to flatfield correction.

Tested 2 first generation Canon 100mm macros and found that one was sharpest at F4.5 and second copy has same sharpness around F5.0-F9.0. So I’d say it’s no point to trust just reviews as there is difference from copy-to-copy.

It doesn’t matter if the problem is just caused by the lens, or if it is the lighting in the room, or whatever. Flat field correction will eliminate the problem in the digitized negatives. It is very easy to capture a flat field frame before the first film frame, then apply that correction to all frames digitized in that one session. Just start capturing a blank frame at the start or end of each digitizing session to eliminate any artifacts from uneven lighting or lens issues.

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Does the Flat Field Correction frame need to be totally blurred / out of focus? My first test was only slightly out of focus with the black mask still distinguishable and lightroom wasn’t recognizing it as an FFC frame.

Yes. With my scanning workflow, I shot my roll of negatives, then removed the negative carrier from the front of the rail, set the camera to manual focus so that the light source was out of focus and adjusted the exposure (I had to reduce the exposure time since the light source by itself is much brighter), then shot the calibration image. Then in Lightroom, I turned on automatic Lens Corrections and set the white balance on the calibration frame, then ran Flat-Frame Correction before making any adjustments to the scanned negatives. The tool runs quickly and exports the corrected images as DNG raw files which can then be processed normally using NLP.

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I had some success with Flat Field Correction. Seems to solve the problem! However I’d still love to figure out what’s causing it. It really seems like it might be vignetting from the lens so maybe I’ll look for an alternate cheap macro that I can adapt to my X-Pro2. Maybe the Nikon Micro-NIKKOR 55mm f/2.8 Lens?

With FFC:

Without FFC:

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Thank you very much for description! It has improved my scans! Now there’s no need to turn out the lights.