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Serge Gregory

Camera Flicker

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When I received my scanned footage (Kodak 7203) back from Spectra, they indicated "camera flicker." It's inconsistent (not in all shots) but very noticeable towards the end of my edited footage: https://vimeo.com/170814555.

 

The camera is a Bauer C61XL. It has a low-light, 225-degree shutter. When I looked at the problem shots frame-by-frame, it was clear that the exposure was inconsistent. It reminded me of the flicker in an old wind-up Bolex. Can others confirm by looking at the footage that the shutter is the likely problem, rather than something else? Otherwise, the scanned 7203 looks very good.

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Yea it did look pretty good. The flicker is very strange because it's inconsistent. The one thing that seemed strange is the gate wobble, it had LOTS of it, more then it should. Outside of a light leak and light bouncing around between the shutter and lens, I don't know what else can cause that issue since it doesn't seem to be consistent.

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Yea it did look pretty good. The flicker is very strange because it's inconsistent. The one thing that seemed strange is the gate wobble, it had LOTS of it, more then it should. Outside of a light leak and light bouncing around between the shutter and lens, I don't know what else can cause that issue since it doesn't seem to be consistent.

Thanks for your response, Tyler. I guess I attribute the gate wobble to a failing of older cameras like this. I wonder whether the new Kodak camera will be designed to minimize the registration issue common to Super-8 cartridges (short of the Logmar solution). My take away is that although this Bauer has great glass, it's no longer reliable.

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I'm now thinking of replacing my Bauer, but before I do, I'm wondering whether anyone thinks the inconsistent shutter flicker and gate wobble discussed above is something that can be addressed in a CLA or repair. I was thinking of calling the Photo Center in LA, which is recommended by Spectra. Again, the footage can be seen at https://vimeo.com/170814555 .

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The scan looks very clean, but sometimes flicker (and unsteadiness) can be introduced during scanning, so perhaps make sure that it's definitely the camera and not the scan.  Have you analysed the actual film to see if you can spot the fluctuations in exposure?

It might be worth getting the same film scanned by a different place to see if it looks any different. 

 

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I took a look at the film on a light table with a loupe and I couldn't see any exposure fluctuations. It's a bit tough since it's a negative, but when I looked from frame to frame, I couldn't make out any change in the density of the image. So perhaps you're right, the problem may have been with the scan--a bit odd since when Spectra returned the completed order, they noted "camera flicker" as the problem rather than any issue on their end.

I guess the only way to know for sure is to have it re-scanned by someone else or shoot a test roll of reversal, have it developed and take a look to see if there are any exposure fluctuations.

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A quick foll of reversal projected might help. I had a similar mild flicker with a 16mm that was solved with a CLA. Your motor might be fighting friction. 

Checking by eye would be pretty hard. 

Would there be a way of using a table top scanner to bring a few frames into a photo program?

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The shots in question with the 'flicker' appear to be tripod mounted shots. If so, you need to block off the viewfinder eyepiece.   Unless many Super 8mm cameras are held to the eye for filming....extraneous light gets into the viewing tube and can affect exposure, which appears as flicker because the stray incoming light is flickered by the shutter and getting to the film.  Some cameras have a viewfinder light shutter to prevent this, others don't.  I don't recall if your BAUER does or not.  As for the side to side weaving, that could also have occurred in transfer. If not, it can sometimes be due to over or under width film, film not having seated correctly in the gate, thus the variable pressure pad on the one side isn't keeping the film in position. This pad allows the film to maintain guidance along one side of the film gate, and it is designed so it will 'ride' any film width changes, yet maintain that pressure to prevent film weave.  Since many later BAUER cameras are rear film loading, it might be more difficult to examine that pressure pad along the side.  However, you can place a short piece of film into the gate, pushing it into position with a long Q-Tip and see if the pad holds it in position. If not, you'll know the pad has too much slack. It can sometimes be bent slightly to provide the needed pressure against the film side.  This becoming weak though is quite rare.  First, hit each possible variable that could be causing this 'flicker', and via process of elimination you'll find it.

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Martin, thanks for taking the time to offer your suggestions. This model of Bauer doesn't have a switch to block the viewfinder, so it's quite possible that the flicker is from stray light, especially since it is visible only on some shots, not consistently throughout. Most of the shots were taken using a tripod, and the problematical ones might have had strong front lighting on the subject. I did manage to test a short piece of film placed on the gate, and the side guides did hold the film in place. I am having the film re-scanned by a different vendor to rule out any scanning issues. I'm beginning to think that stray light bouncing around is the problem. I read somewhere that it works to tape a toothpaste cap over the viewfinder lens.

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