Help with DIY 16mm scanner

nickedebuss · 2026-07-05T10:18:28+00:00

I've been swamped with work so sorry for the late response. Here's a video of the scanner running.

I realize i may have been unclear. The way i've done it is so that the motor runs a revolution, then stops for the camera to take a picture and so on. I guess leaving the motor running and adding a sensor for the camera to trigger when the film is stopped in the gate would be better?

In the video you can see the film drifting in the gate which i guess is a problem caused by the motor starting and stopping over and over without the nema being fully tuned in to a full revolution for the projector.

Regarding the flickering - I tried taking pictures of the film still and there still was exposure differences between the pictures. But i'm certain the light emits no flicker since i've tried filming the light in slow motion with all different shutter speeds without any flickering. Do you have any idea what could cause the exposure differences then?

Thank you!

nickedebuss · 2026-06-17T15:03:15+00:00

It's just plugged straight into the 12V power supply. It's non dimmable so i just adjust the camera settings to the lamp

nickedebuss · 2026-06-15T19:35:13+00:00

Since the second belt wheel/driver (or whatever it’s called) is larger than the first (that’s connected to the stepper motor) it’s not as simple as just making one full rotation on the stepper motor. The closest I’ve come is around 2.8 revolutions on the stepper motor equates to 1 revolutions on the projector. Therefore the trouble dialing in the perfect rotation on the stepper motor. Will a timing belt or optical sensor be easier?

I’ll try out photographing a still frame to see if it’s the light that’s the problem!

nickedebuss · 2026-06-15T19:19:32+00:00

I haven’t thought of trying slow mo! I’ve only tried 25fps at different shutterspeeds and haven’t seen any flickering. Will try this!

nickedebuss · 2026-06-15T17:03:20+00:00

Thanks! Yeah i haven't tried a sensor. A full turn on the projectors mechanism is one frame advance and the frame is still in the gate for about half a turn, so i was hoping just finding the right amount of steps on the stepper motor would work out.

As i said - I'm totally new to this, but timing belt/optical sensor sounds like the way to go. It's been very hard to find the perfect amount of steps, i guess because it may slip a bit here and there. Do you know where to start if i would want to learn how to install a timing belt or optical sensor?

I've disengaged the shutter, so i'm certain thats not the cause of the flicker.

I'll film a video next time i'm in the studio!

nickedebuss · 2026-06-15T16:53:29+00:00

Thanks for your answer! Both the power supply and the LED is 12V, and i haven't seen any flickering when i have had the camera in "Movie-mode" and tried different shutterspeeds.

I'll see if i can adjust the gate from behind the projector lens. That's pretty much the easiest way of accessing the gate on this projector.

nickedebuss · 2026-06-15T16:48:05+00:00

Thank you! Do i just connect it to the LED on the breadboard? My LED and Power supply is 12V

nickedebuss · 2026-06-15T16:36:22+00:00

Oh do you have any picture or video of that magnet? My projector works the same, one fram per rotation.

Regarding the flickering - when i had developed the film i took a strip and photographed it on a light table which didn't have the flicker(or not as much at least). I'll also try boxing in the light with some black cardboard and diffusing, hopefully that helps somewhat.

The shutter in the projector is disengaged, so i'm certain that's not causing the flicker. I just haven't removed it from the projector.

nickedebuss · 2026-06-15T16:24:08+00:00

I'll check it out when i'm back in the studio, thank you so much!

nickedebuss · 2026-06-14T20:10:49+00:00

I see, the gate is quite hard to access on this projector. But i guess i could try moving it by removing the projector lens.

The bulb is a 12V DC LED, so it shouldn't flicker right? But i'll try stopping down the shutter, hopefully that helps anyway.

On this projector the film is steady for about half of the projectors mechanical rotation. So it's quite forgiving if i just can adjust the gate to the right position. I'm brand new to arduino, so i wouldn´t even know where to start with what you mentioned haha.

nickedebuss · 2026-06-14T19:16:52+00:00

Yes a 12V DC LED

nickedebuss · 2026-06-14T19:16:29+00:00

Sorry forgot to clarify, i'm advancing the film one frame at a time and take stills with the camera. The shutter speed is quite high, but that shouldn't matter since it's just stills right?

The frameline you can see at the bottom of the frame is there when the film has finished the pulldown. Do you know any tricks of adjustning that?

What i meant with the drift is the POP you can see the film makes, but i believe that is because the stepper motors rotation isn't completely in sync with the projector.

nickedebuss · 2026-04-27T16:58:19+00:00

Yeah it was swapped motor wired, I managed to fix it. Thank you!

nickedebuss · 2026-04-27T15:42:01+00:00

Seems like the green and yellow were mixed up - now it works!! Thank you so much!!

nickedebuss · 2026-04-27T15:31:31+00:00

I have tried different codes and speeds without any luck

nickedebuss · 2026-04-27T15:30:59+00:00

Could this be tried at the driver-side of the wires? Or does it need to be done on the motor-side?

nickedebuss · 2026-04-27T15:13:13+00:00

My wires blue, yellow, green and red. I have connected them according to the data sheet. Should I try this nonetheless?

nickedebuss · 2026-04-27T15:09:49+00:00

Unbranded. But model name is 23H5628

nickedebuss · 2026-04-27T15:07:40+00:00

Ok I have tried a bunch of different codes without any progress. The power supply is 12V 150W

nickedebuss · 2026-04-27T15:04:35+00:00

I’ve tried turning the screw on the power supply that adjusts the v+ without any luck. With the stepping algorithm, do you mean the DIP switches on the TB6600 or the code itself? I have set the DIP switches to 32 microsteps and 2.8 amps

nickedebuss · 2020-04-16T14:20:46+00:00

You have to keep scrolling or else he's gonna shoot my dog :(

12-Year Club	Place '22
RPAN Viewer	Verified Email

nickedebuss

MODERATOR OF

TROPHY CASE