Ian Brennan

Hi there, I actually combined two different approaches. I struggled getting a good resolution using any sort of Macro lens directly off the gate. I tried (like others) to use USB microscopes but couldn't get them close enough to be useful. So, I went back to basics, used the projector lens to project onto a magnifying glass. then put the camera behind that. With the lens I had it meant I needed lots of space to spread out. Now, it's worth reviewing what the rotor and the gate do on a projector. They do 2 things, they removes flicker by increasing the "flashing" rate of the image and it hides when the film is pulled through the gate. The movement happens behind one of the "fins" of the rotor. Otherwise you'd see a blur. So, removing the rotor from the gate exposes the blur. If we video that image (either using the magnifying glass or directly off the gate) and we film at 2-3 times the gate rate, we can use that blur to indicate when the cine frame is moving, and if there's no difference between video frames, then we're seeing the stationary part of the rotation.

Footage here - skip half way through to see the completed film

@Pol, great piece on your development. I see you use a stepper motor... would you be able to say what type it is and how you drove it? I can see the reed switch etc. I've also been working with the same projector - very easy to crack open. I have three, one I stripped down completely, one I've partially stripped and a 2000 to show film with. 2016 is the year to get back into the build... I've tried a different approach that some may find useful. I removed the interlace shutter, used used a different approach, letting the original motor run as slow as I could. Then used a front-mounted lens (like a magnifying glass) and project the image onto that (i.e. using the projector lens as it was designed). If you do that, you get an inverted image that's big enough to capture with a normal camera. Now, if you use your camera in HD video mode, you can capture the film as it runs. The trick is that without the interlace, the video captures the stationary image and the image in transit.... and you can detect the transition between the two by post-processing the video stream. I describe it here.... http://forum.doom9.org/showthread.php?t=168830 and show an example. My next stage is to probably capture it off the gate directly, using a stepper motor to drive the mechanism rather than the original motor..