I am trying to copy old 8mm cine film to digital using a projector
I have been through hoops of trial and error and have settled on videoing the actual film itself using a close focus lens looking directly at the film gate (i.e. emulsion side) with the projection lens removed as it gives incredibly sharp results and colour, the camcorder produced HD mp4 file only needs flipping which I can do quickly in my PC video editing program and the resultant video looks excellent even on a 55" OLED TV
I need to closely and very precisely control the 12V DC motor that I have fitted to the projector as it MUST run at a precise speed (of around 2700 RPM via the geared pulleys) to give the required 16 2/3 fps on the projector shaft - which equates to 1000 RPM........ handily, with the 3 blade blanking shutter in the projector this translates to exactly 50Hz and ensures there are no black bars or sync issues with the camcorder
I have a slotted opto switch that I can mount to the projector shaft to detect the 3 shutter blades as they rotate - I did consider using a magnet and hall output but that only gives 16.66Hz whereas the 3 blades will give 50Hz which should allow a tighter control and wont upset the balance of the shutter plate…..
.....and thats about as far as I have got so would appreciate any suggestions and help in controlling the motor (via a MOSFET) and (if possible) an 8 pin 08M2 PICAXE as I have several going spare
The mechanics are sorted but I have little experience in programming
I have been through hoops of trial and error and have settled on videoing the actual film itself using a close focus lens looking directly at the film gate (i.e. emulsion side) with the projection lens removed as it gives incredibly sharp results and colour, the camcorder produced HD mp4 file only needs flipping which I can do quickly in my PC video editing program and the resultant video looks excellent even on a 55" OLED TV
I need to closely and very precisely control the 12V DC motor that I have fitted to the projector as it MUST run at a precise speed (of around 2700 RPM via the geared pulleys) to give the required 16 2/3 fps on the projector shaft - which equates to 1000 RPM........ handily, with the 3 blade blanking shutter in the projector this translates to exactly 50Hz and ensures there are no black bars or sync issues with the camcorder
I have a slotted opto switch that I can mount to the projector shaft to detect the 3 shutter blades as they rotate - I did consider using a magnet and hall output but that only gives 16.66Hz whereas the 3 blades will give 50Hz which should allow a tighter control and wont upset the balance of the shutter plate…..
.....and thats about as far as I have got so would appreciate any suggestions and help in controlling the motor (via a MOSFET) and (if possible) an 8 pin 08M2 PICAXE as I have several going spare
The mechanics are sorted but I have little experience in programming
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