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Homemade Telecine

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  • Great work David and thank you for the samples. I have some 35mm negative strips and will try to stitch them together.
    I ran some preliminary tests yesterday and everything worked ok but more testing is required.
    The FW currently supports only one format and I will complete the tests with that and then add multiple formats.
    Which LED did you use for the above images?


    • The LED I'm using is the same one I've had for years, just a battery powered small array of leds diffused thru 1/8" white plastic. It's not bright enough for movie capture, some of those exposures are close to 1 second.

      I need to begin assembling the film transport and that will take a while. It's better you have the parts in advance of when you're ready for them.


      • Thanks David. I can start the assembly as soon as I get the parts. Still testing the tuning part. It does have some issues and will take a few days to sort it out. Had a thought about the 35mm negatives. Would it be possible to splice them and put them on a 35mm movie reel?


        • Well, it is certainly possible. There are a couple of things to be aware of.

          BTW, I once worked a movie theater. I would break down the old movie and then splice together the new one. Movies came on abt 5-20 minute reels. We had an automated system, all reels were spliced together and laid horizontaly on a platter/turntable. I had an editing table and the film was placed on the splcer based on the perforations, just as 8mm film. There was a spool of splicing tape that now reminds me of a roll of packing tape. The editor would cut the 2 films, the tape and perforate it.

          As I look at 35 negatives I have in hand, they are not evenly cut at the frame line. To get the spacing correct there might need to be some blank leader added otherwise automated capture framing might change.

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          Also the splicing tape would possibly cover part of the image, but the strips might be spliced only along the perforations.

          Maybe something like that is already being done by commercial scanners?

          There are reels used for 35mm microfilm, I have one.
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          They use a 16mm spindle, though it's longer. That would hold a lot of negatives!

          I think you were happy with the LED you bought. I need to see how I will mount it. Should run off the Wolverine power supply?


          • Looks like quite a bit of work to assemble the reel of 35mm negatives.
            Unlike the 35mm movies the splicing with the negatives can have blank images in between the two clips. So with some clear lead and some sort of alignment jig the two clips can be connected so that the frame sync is not lost. Still lots of work.
            The LED that I am using has adequate brightness but it needs a large heatsink. Will send you the picture tomorrow.
            Currently I am using a 2 Amp dc adapter but believe the Wolverine adapter should also work --- will check.


            • I found a 35mm editing block with pins on Thingyverse. The designer built it to edit motion picture film. I have modified it and tried to find a way to build it to keep the frame spacing when I realised I have been using random strips. With some exceptions, I have negatives in their original envelopes that also held the prints.

              There should be no need to measure spacing if the strips are reassembled by the frame numbers. Wished I thought of that earlier!!!

              Of'course spacing will matter when joining different envelopes.


              • Yes, and I have lots of envelopes so will still need the splicing jig.


                • Received your package David. Will look at it tomorrow.
                  Got the firmware finally working for a single format. Will do more testing tomorrow to make sure it is solid and then try to add other formats.
                  The LED chip that I used crapped out on me. It started flickering like a lightbulb that is about ready to burn out. Luckily, the package contains 10 of them. Hopefully the replacement will last longer. Maybe the substrate overheated at one point before I added a heftier heatsink, not sure but will keep an eye on it (no pun intended).
                  Forgot to mention, tested the Wolverine DC adapter and seems to work OK.
                  Last edited by Stan Jelavic; February 04, 2022, 09:36 PM.


                  • Thank you for the 3D parts David. Tried them today and here are some observations:
                    - The bolts for the roller pulleys are too short in my installation. Will stop by Home Depot tomorrow to see if they have longer bolts.
                    - In my installation the reel assembly sits too high and will require shortening of the mounting hardware. Not a big deal but wanted to mention it.
                    - The reel hub is a bit tight and requires some force to snap it onto the existing spindle. It is still workable however.
                    Other that that everything else seems to be ok.
                    Will provide an update tomorrow.


                    • That is interesting. The reel hubs were at first too tight on my machine, so I opened them up a little. I left it just a little snug so it could not fall off by gravity.

                      Another fit problem is in the negative splicer. The original designer left a slot to cut the 35mm film, inside a 2mm margin between the 36x24 frames is where the cut should be.

                      I thought he was cutting movie film and that's why the margin did not line up with the cutting slot. I grabbed a couple of negative envelopes to see where the cut should fall relative to the perforations. It was just a little off-center. After so much measuring and printing, I searched online for picures of 35mm negatives. There are only half a dozen out there, but they all have the margin centered between the perfs.

                      So I dug up more of my negatives, and the margin is centered sometimes. Looks like it varies by camera.

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                      I do have a solution, but more on the splicer later.


                      • That could be an issue and frequent adjustments may have to be made during scanning. Will check my negatives.


                        • Assembled your 3D parts David.
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                          Will test it tomorrow. The unit is now capable of R8,S8 and 16mm scan. For 16 mm the 16mm gate has to be swapped for the 8mm and the reel posts have to be changed to 16mm, a simple mod.


                          • Great pictures. I've been starring at them for 15 minutes!

                            It's exciting to be able to see everything so clearly.

                            Good luck on the testing.


                            • Thank you David,
                              The LED chip is not connected in the picture. It goes to the bottom right of the controller board close to the DC adapter plug. It does not have a connector at this point but will figure something out to make the disassembly a bit easier.
                              I modified the FW for 4 film formats.
                              The formats can be whatever the user choses since each one has its own tuning.
                              The FW selects the format at power up. It checks the status of the REW and S8/R8 switches to create 4 format combinations.
                              The format cannot be changed while the board is powered up. You have to power the board down, set the switches and then back up.
                              After that the S8/R8 switch does not have any effect and the rewind switch can be used as a rewind if run sw off and as a tuning control if the run sw is on.


                              • It sounds simple enough to operate. The horizontal layout is nostalgic, reminds me of a tape recorder!

                                I thought the orange block might be the heat sink for the led. Just something you had on hand?