Hello everyone,
I built this machine 4 years ago with the help of you fine folks and converted a dozen 200' reels of my families old 8mm film. I just found another 2 400' reels whichI somehow missed, however, the machine vision camera I had used has crapped out since I last used it so I bought a new one and have it installed and working again. It's much faster than the old one and I'm able to capture at 6fps now vs 3 for the old one. I was happy with the performance of the old setup but while I was tuning the new camera white balance without any film in the machine, I noticed that some of the frames were darker, seems every 3rd or 4th frame was noticeably darker. It wasn't an issue while I was capturing as I think the camera exposure masked the effect, but being a perfectionist, I would like to figure this out.
My machine is driven by an Arduino ucontroller and triggers the cameras electronic shutter and LED light. There is a magnet and hall effect sensor for the trigger mechanism, the shutter wheel on the projector has 3 openings. I guess I gave you more info than needed but what I need to understand is how the old projector was designed to work, ie, why 3 holes on the shutter wheel, 5 on some projectors, why not just one for when the film is stationary in the gate? My projector shares the shutter wheel with the cam drive for the claw so eliminating it is not an option. I'm thinking I may be able to elongate the openings significantly to allow more "open" time for the capture without compromising the structure of the wheel. I'm trying to just capture one frame at a time, exposure is about 10-15mS.
I look forward to getting some some fresh ideas from you, I'll be working on it again tomorrow with a fresh brain, it all may make sense to me in the morning but thought I would ask. Here is a video of my machine shortly before finishing it 4 years ago and a sample of the finished, processed film, 1970.
Thanks all.
Paul
https://drive.google.com/file/d/1KWH...ew?usp=sharing
I built this machine 4 years ago with the help of you fine folks and converted a dozen 200' reels of my families old 8mm film. I just found another 2 400' reels whichI somehow missed, however, the machine vision camera I had used has crapped out since I last used it so I bought a new one and have it installed and working again. It's much faster than the old one and I'm able to capture at 6fps now vs 3 for the old one. I was happy with the performance of the old setup but while I was tuning the new camera white balance without any film in the machine, I noticed that some of the frames were darker, seems every 3rd or 4th frame was noticeably darker. It wasn't an issue while I was capturing as I think the camera exposure masked the effect, but being a perfectionist, I would like to figure this out.
My machine is driven by an Arduino ucontroller and triggers the cameras electronic shutter and LED light. There is a magnet and hall effect sensor for the trigger mechanism, the shutter wheel on the projector has 3 openings. I guess I gave you more info than needed but what I need to understand is how the old projector was designed to work, ie, why 3 holes on the shutter wheel, 5 on some projectors, why not just one for when the film is stationary in the gate? My projector shares the shutter wheel with the cam drive for the claw so eliminating it is not an option. I'm thinking I may be able to elongate the openings significantly to allow more "open" time for the capture without compromising the structure of the wheel. I'm trying to just capture one frame at a time, exposure is about 10-15mS.
I look forward to getting some some fresh ideas from you, I'll be working on it again tomorrow with a fresh brain, it all may make sense to me in the morning but thought I would ask. Here is a video of my machine shortly before finishing it 4 years ago and a sample of the finished, processed film, 1970.
Thanks all.
Paul
https://drive.google.com/file/d/1KWH...ew?usp=sharing
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