Homemade Telecine

[Stan Jelavic]

Thanks David. The drift is minimal. Ran 1000 frames without any noticeable drift. The shake is there but no drift. The deshaker will take care of the drift also but you do not want too much of it because will result is large crop of the edges.
Yes, planning to try the pinch roller. Would like to try your rubber bands if you could send me the info on where you got them.
For R8 film the gate has to be wide enough. Since the gate has to be widened up anyways for the sprocket hole then might as well make it wide enough for both formats. The MSP430 can be programmed for both formats and can be controlled by a switch.
A note on two different sprocket wheels needed -- I will try the rubber pinch rollers. If that works then no need for two different wheels.
The image quality was not the intent of the test. I did not even bother to check if everything is in focus.
The LED assembly needs some improvement. There is still some light scattered from the side of the LED hole that results in some minor scratches being visible on the left side of theimage.

[Stan Jelavic]

Was thinking of getting these rollers. Any other ideas?
https://www.fruugo.us/recorder-parts...RoCpe4QAvD_BwE

The final assembly would look something like this.
https://forums.kinograph.cc/t/my-rpi...mms-design/639

[David Brown]

Awesome find Stan.

I was never able to find NEW recorder pinch wheels in previous searches. Guess you can't buy just one!

4 motors on the "Kinograph"? I didn't read the text, just the picture. I would agree with the 2 motors, one on each side of the camera.His capture seems free of drift. I wonder if some of the shakiness we see isn't recorded by the camera?


OK, here is the Amazon link to what I bought for the capstan.

https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

Since 200 come in the package and I only used 1, I tossed a handful in the mail for you. Up to you if you want these sooner or later.

The one I'm using on the Hawkeye's capstan has not lost any traction yet. The spares are kept in a sandwich bag.

I have been looking at these below for possible use as a pinch rollers. I don't know what to expect with the coating.

https://www.amazon.com/dp/B01HD5KKOA...v_ov_lig_dp_it


I thought about applying some kind of rubber tape like this with unknown materials or diameters.

https://www.amazon.com/dp/B08PK7JDZY...v_ov_lig_dp_it


So is the final diameter an important consideration?

Feel free to correct me on this.

Using 1.8 degrees of rotation for 1 step and a target of 0.1667" of travel that becomes a radius of 5.3" roller in the calculator. Divided by 10 to get to a more practical diameter means 10 steps to hit 0.1667" of movement. To include 8mm a common multiple could be used.


How important do you think this is? Does the optical sensor play a bigger role here?

Projectors are using a metal rod tied to a flywheel and a rubber pinch wheel on the other side of the film. That's done in tape recorders but for film seems like both should be rubber.
Maybe the motor's shaft could be used with 1 rubber pinch wheel?
A coupler might be need to avoid the flat.

https://www.amazon.com/Printer-Coupl...+motor+coupler &qid=1633368965&sr=8-2

[Stan Jelavic]

Hi David, the Kinograph picture is a very rough idea and I am looking at using only one stepper with a pinch roller. The other roller in the transport would be only passive rollers like in Wolverine. The gate tension in that case has to be setup properly. Possibly use adjustable tension spring loaded gate.
Thanks for the links and the samples that you sent. May be able to use them at some point. For now I am thinking of getting a set of rollers from the link I sent out and see how well they work. The size is not that important in my opinion since the stepper is 1.8 degrees/step but also it has 128 microsteps ultimately we have (1.8/128) degrees/microstep. That is why I was able to fine tune the current setup with virtually zero drift over 1000 frames.

[David Brown]

My search was for a Super8 projector in hopes of using both R8 and S8. R8 has a smaller aperture so S8 would handle both.

Not true. I had only to look closer at the specs.




There are no dimensions from the frame to edge of film opposite the perforations on R8.
The image above is visually accurate and the margins look different. So even though the S8 frame is larger, it crops the R8 image on one side.

These pictures below were shot using a S8 camera gate. Even if the gate is flipped, there is more image loss.



I dismantled an old S8 camera for the gate. I will now try to widen that camera's gate. If that fails, back to Ebay!

So yes, I had to order a S8 cartridge to get a pressure plate!

I've looked at a lot of projectors on YouTube and images trying to see the gate parts. My favorite so far would be a Eumig Mark 8 (S8/R8) the gates just slide in and out as does the pressure plate. Nothing to dismantle! Need to find one selling for parts.

And maybe I will have to print my own gate? I do have practice films.

[Stan Jelavic]

Printing the gate could work out ok. If done right the gate and the pressure plate should not be touching the image area of the film, only the sides which should minimize the chances of scratching.
I am waiting for pinch rollers and once I get them I will do a quick test with my existing prototype rig.
I am also thinking of getting rid of the Wolverine power supply and replacing it with a 128 micro-step controller. Possibly something similar to this one.
amazon.com/EASON-DC20-50V-Subdivision-Controller-MicroStepping/dp/B08RHLDZD5/
That way the only components used from the Wolverine would be the reel components which can be relatively easily replaced with something else. But Wolverine may be willing to sell these and generally their part costs are not that bad.

[David Brown]

Not so bad, opening up the gate. It went pretty fast once I got some tiny files. Must be made of aluminum. I'm waiting on the Super 8 cartridge, about a week from now. If the pressure plate works out, I'll move on.


I have retired the Winait scanner. I'm able to use any parts from that.

[Stan Jelavic]

That worked out very well David. Great idea to use the cartridge. It has a pressure plate and might do the trick.
https://www.youtube.com/watch?v=dsUwhHv5HZI

[David Brown]

Thanks, Stan that is valuable information about the Super 8 cartridge.

Posted in 2019, unexpected. Saves me from buying another cartridge if I were to mess up the first one!

A projector is the first choice over a camera. A thrift store once was the best place to find one. That might not be as easy today as it was 20 years ago.

I bought the Super8 camera for $5. It was a Kodak XL. I thought it was an interesting design, like binoculars. But it' been in a box for years. I never intended to use it, just put it on a shelf.

[Stan Jelavic]

Actually found another stepper controller that runs from 12V. It is also 128 microsteps.
https://www.amazon.com/gp/product/B0...M55UG43X&psc=1
The interface is TTL which can be connected directly to the MSP.

That is a nice looking camera. Reminds me a bit of the SX-70.

[Stan Jelavic]

Found a stepper controller with 256 micro-steps but it is more money.
https://www.pololu.com/product/3141

[David Brown]

256, that's twice the movements. That is 200*256 positions?

I don't know enough about stepper motors and controllers to evaluate the extra cost. The software that comes with the controller looks very detailed, but can it be used with this application?

I watched the software demo and found it fascinating. I have a lot to learn.

The claw is a very precise method. That is if it is designed well. The Wolverine has problems and that could be the gate pressure or it's claw motion and size. I remember the Wolverine claw cam and thought it was clever. I found the same plastic claw cam in the Kodak S8 camera I just tore down.

So about micro steps, this homemade telecine could then be adapted to 16mm, with another gate, or even to a future HawkeyeII? For those like Kamel with damaged perforations or others, if it improved the gate stability over the claw?

Just an illustration to show the motor and rollers mounted outside the housing. I'm not sure it could fit inside.

[Stan Jelavic]

Yes, it is twice the precision, theoretically anyways. I bought the one with 128 steps and believe that it should be enough precision but we will see. Most of the projectors and cameras with a claw use that type of the cam design. It is pretty ingenious. Someone spent lots of hours trying to figure out how to put this together, I am sure. DaVinci, maybe Never mind, silly me.
The Wolverine pinch roller idea is a good one but as you said it it would have to be an external assembly. The Nema17 motor is pretty big, perhaps something smaller may work.

[Stan Jelavic]

[QUOTE=David Brown;n44067]

So about micro steps, this homemade telecine could then be adapted to 16mm, with another gate, or even to a future HawkeyeII? For those like Kamel with damaged perforations or others, if it improved the gate stability over the claw?

Yes it could work with any size film providing the gate is changed and possibly the reel mounts.

[Stan Jelavic]

Received the pinch rollers today. Looking at the ways of installing the idler roller. Possibly use the
2.5mm shaft
https://www.amazon.com/uxcell-Lathe-...dp/B07KY8RJ6J/
and the end stoppers
https://www.amazon.com/Accessories-P...dp/B089YYZ2VX/