It’s not required, but it’s very helpful if you can provide a link to the original RAW or TIFF negative before conversion. If you don’t want to share this file publicly, you can also email it to me at nate@natephotographic.com Conversion Help - Google Drive
Many but not all of my exposures from this roll show this issue. I don’t think it’s on the physical negative because the issue didn’t appear after full-frame re-scanning. I can’t / don’t know how to tell whether the issue is present on the digital negative. Maybe the lower sprocket holes in the raw file are the problem? I cropped them out before conversion, but it doesn’t seem to make a difference.
I think this will be interference between your camera shutter and the frequency of the LED light panel since there are only 8 sprocket holes across a 35mm frame. Check the shutter speed used for those that don’t have this banding or try switching to the mechanical shutter if you are using electronic (silent). However I am surprised that the bands are vertical as I presume that your camera has a vertical shutter which would produce horizontal banding.
That’s brilliant Harry, thanks for responding. I thought the same thing about there being too few sprocket holes to have caused the banding. I’ll reach out to the folks at Negative Supply to find out what the frequency of the LED light source is. My shutter speed was 1/5 of a second, perhaps 1/4 would work better.
Have you encountered this problem before? Is there anywhere you’d suggest reading more about it?
I think that you can discount the sprocket holes but it doesn’t quite make sense because the bands are vertical. Perhaps it has something to do with the panel itself so NS might be able to help, or hopefully someone else with either your Canon or that panel will chip in. If you google ‘Canon R8 LED banding’ or even ‘Canon R5 LED banding’ you will see various posts about LED stage lighting etc, but then the banding is horizontal, the Canons do seem to suffer from it more than others though.
Can you see any kind of relationship between the actual shutter speed and the severity of the banding? In theory it will occur when the shutter speed is a precise fraction/multiple of the frequency of the LED panel. Are you using the ‘silent’ shutter? Any clues that you can give will help others to solve this.
I haven’t encountered it but I’m using a Fuji with a shutter speed of around 1/125 sec frowith a CS-Lite, it doesn’t mean that I won’t though. I have encountered banding outside from giant LED screens with my Fuji using the mechanical shutter. I did change the shutter spped as much as condotions would allow but it didn’t make much difference. Mind you it’s hardly likely that NS have designed their expensive panel in a way that would trigger this.
I’ve done some experimenting. Dusting off my light source, sliding the lens’s focus range tab, and turning off stabilization did not independently make a difference. Throughout this process and testing, I have not been using a silent shutter.
I took six shots of one of the negatives that had prominently shown the issue. Three shots of the negative without its borders and three shots with the borders. Each set of three was shot at 1/2 sec, 1/4 second, and 1/5 second shutter speed.
Shooting at 1/2 second seems to have alleviated the issue. 1/4 second shows banding, and 1/5 second looks the worst. Shooting with borders helps a small amount, but shutter speed matters the most by far. I think this gives merit to your interference idea.
I arrived at 1/2 second by adhering to point #7 in this article:
I’m not sure whether the position of the negative on the histogram is relevant or just a coincidence though.
That’s really interesting, and just the sort of methodical testing that is required to try to get to the bottom of this. It is definitely looking like interference with the panel frequency and your camera but I don’t really understand why this should be so, and why the stripes are vertical. I found another thread on here where the last comment from ‘XPan’ seems relevant:
Note that ‘XPan’ is using a highly recommended Kaiser SlimLite Plano 2453 which many on here use, it’s similar to your NS panel in that is is relatively dim so requires longish exposures, but it seems that he couldn’t use it with his Canon EOS R because of interference patterns.
I imagine that you might be using a negative holder where the panel is integral but if it was me I’d be really interested to know what happens if the panel is turned through 90º with respect to the negative (i.e. does the orientation of the ‘stripes’ change with it?) but that may not be possible to do easily.
I’m not sure if the interference disappeared completely at 1/2 sec but if so then it is does mean that you’re limited to 1 stop steps when setting the exposure assuming that you want to keep the aperture the same, you could live with that though I suppose.
I did read that your camera only has an electronic first curtain shutter, could this be something to do with it I wonder?
If it is some kind of mismatch between certain EOS R cameras and the NS panel then I suspect that NS will know about it and so may be able to help.
I can rotate the LED panel freely. Next time I scan negatives, I’ll pull one of the problematic frames from this roll and test.
Negative Supply also asked about whether my camera uses an electronic shutter. Unfortunately they didn’t supply a frequency for the LED panel or comment further.
I rotated the panel. Interestingly, bands appeared in the same orientation as before.
NS also suggested I check my anti-flicker settings. The R8’s anti-flicker, HF or not, is disabled by default. When I tried using the HF flicker auto-detection with the camera oriented towards the panel, no flickering was detected.
Unfortunately I can’t try shooting with anti-flicker enabled. For some reason only shutter speeds of 1/50 or higher are allowed.
Well thanks for trying anyway, I’m floundering a bit here now. It’s pretty clear that if the panel caused this effect with a cross-section of cameras then we’d hear about it on here but I suspect that your combination of that panel and the Canon R8 is not common on here at least. There is a ‘Negative Lab Pro Users’ Facebook forum where it might be worth asking the same question, ‘Digitizing film with a digital camera’ and ‘Digital Film Scan Tools’ are two other relevant FB forums. They’re ‘Private’ but it’s not a problem to join.
Negative Supply followed up with me, and I received a replacement panel to test this week. I’ve just scanned the same frames with the same settings as before, and the color banding is gone. I’ll report back if the issue recurs, but at this point I think it’s safe to say that I had a faulty panel. I’ll offer to send it back to NS for failure analysis. Hats off to them for sending a replacement even when I was unsure of the source of the problem.
