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Wolverine MM Pro problem with Super-8 please help

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  • #16
    Hi Kamel, I had a brief try with the Goko RM5000 idea but didn't get very far. I tried it with the existing bulb, which is pretty low output for this project (been unable to find a more powerful LED replacement). I placed some white paper over the mirror but I couldn't even get a recognisable picture at all. It would probably have been better in total darkness maybe but I kind of felt it wasn't worth pursuing without a much brighter light source. I have now decided to use the 'down the lens' method that was featured on here a while back:

    https://8mmforum.film-tech.com/cgi-b...c;f=1;t=009763

    I did a little 'test of the concept' using my Eumig with it's existing lens (but not turning the selector knob fully forward, so that the lamp is not illuminated - there's enough light in this position to test it) just to see for myself and was amazed at how well it worked (apart from the vignetting and hotspot). I am now sorting out a 16mm lens to use so that I can copy the full frame almost 'off the gate'.
    Last edited by Gary Sayers; April 11, 2021, 08:41 AM.

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    • #17

      hello Gary,
      I had already tried this method lens to direct film) with a modified workprinter but too many camcorder alignment problems.
      I had tested in 4K the results were magnificent but the quality was not uniform on the frame due to the complicated alignment of the capture camera.
      I gave up to go back to Wolverine and then to Stan Jelavic's Hawkey which really improved the catches.
      But there remains the big problem of jitter on this type of device and the long capture time.
      My dream is to digitize in 4K for maximum quality for our precious memories.
      What would be good would be to be able to integrate a small fixed card camera in the goko 5000 but I have never tried.

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      • #18
        Hi Kamel, have you checked the transport mechanism of the Goko? Is it solid enough and how is the jitter? If the mechanics are good enough the rest of it should be doable i.e. the lens, the camera and the cam mounting. What was the 4K cam that you used? How was the flicker?

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        • #19

          hello Stan,
          I had used the Sony FDR-AX53 (carl zeiss 20x optical camcorder), with a Raynox 250 macro lens ..
          My tests were done on a modified workprinter XP. (Not tried on the Goko RM5000).

          There is no jitter or flicker on the Goko but it is a prism which rotates the image of the film, returned to a small mirror then to a frosted screen.
          The image is very dim and unusable... maybe replace with a Led.
          Hence the idea of ​​fixing a small camera board type BUC02 inside so as not to have the problems of flatness and good alignment.
          There are still ideas for a real-time scan (the Goko RM5000 works in 18/24 or 25 quartz images per second).

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          • #20
            Kamel, I've just tried, out of curiosity, the Goko again in total darkness and although a reasonable picture can be seen, it's still too dim to be of any practical use with it's current bulb. A replacement LED should do the trick if one is available.

            My initial idea of simply pointing a camcorder at the mirror area is also a bit of a no no due to alignment problems. I guess your idea of installing a small camera inside would be the way to go but that's getting beyond my skills.

            Also, the illusion of marks and scratching that is produced by the prism is just so annoying. No amount of cleaning on the prism gets rid of it completely (at least on my machine).

            I will call it a day on this idea.

            I will be interested to see how you progress with the idea (if you keep going with it) and good luck with your efforts on it.

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            • #21
              Thanks Kamel. Wow that is a pretty expensive camcoder. One quick test would be to try the camcoder with the Goko screen and see if it can be synchronized. If so possibly look at direct projection and some type of mechanical mounting to the Goko hardware.
              Another possibility as you suggested is to scrap most of the Goko and use the transport with one of the TIS cams. Would have to figure out how to sync the cam. Possibly timer mode.

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              • #22
                I do remember that the BBC once used a telecine using a prism, called the Polygon telecine. It did sometime blend frames at 25 fps. However it was best when transferring silent films that could be at any frame rate to video (with a lot of frame blending) without flicker or jerky motion). So th eGoko idea has a commercial precedent.

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                • #23
                  After trying to improve the image quality of an editor/viewer, I think it should not be your first choice as a telecine.

                  A puny light source and at least 3 mirrors and a rear screen are between the film and your camera. They should all be front surfaced mirrors to prevent ghosting, but they're not because it's just a viewer. The frosted screen can have hot spots, depending on the viewing angle.

                  Why not reverse the whole process?

                  Shine a light thru the screen and (after removing the lamp housing) shoot down on to the film?

                  Of course there is still that prism, a rotating glass cube that is briefly parallel with little distortion. A cheap shutter.

                  Click image for larger version

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                  • #24
                    I do not have the viewer David so at the 10000 foot level I am thinking get rid of all the optics and use the transport only if it is good enough quality.

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                    • #25

                      Good day all,

                      the goko was just an idea to have real time scan.
                      but yes Stan, is going to be a bit complicated and I think I will get back to Hawkeye very soon.
                      David your idea of ​​reversing is a very good lead. Test to be done.
                      My problem with Hawkeye is jitter and lack of focus precision.
                      I had bought a small 25mm support slider, but I have not yet found the idea to integrate it into Hawkey. To think

                      Stan, If you decide to make a Torulf Holmström T-scan type telecinema, I will be the first buyer!
                      I am ready to do all the 3D parts but I am not an expert in electronics.
                      But it's still a good idea that can be improved.
                      I would like a Retro8 Moviestuff type telecine, but affordable.


                      Gary, I don't think I will continue my tests too far with the Goko for lack of time.
                      I'll go back to Stan's Hawkey. Otherwise maybe a Telecine from A to Z type T-Scann from Torulf Holmström.
                      I like the idea of ​​transporting the film by clawless capstan

                      it will also be easier to integrate any shooting camera, we are master of the system.
                      I think it will be easy for stan to adapt our TIS camera, and me a very precise focusing system.
                      My dream : 4K S8 Telecine
                      Attached Files
                      Last edited by Kamel Ikhlef; April 13, 2021, 09:19 AM.

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                      • #26
                        What spacer are you using with the BUC02 Kamel. I find the 3/8" spacers to be optimal for the 12mm lens. Going shorter than that will cause focusing issues. How extensive is the jitter? Can it be fixed in Post? Have you looked at my aluminum duct tape fix?
                        Designing a new telecine is a big project unless we make it as simple as possible but still functional. Using the cog wheel transport seems to be the most elegant solution but it can go out of step with the frames often. Several designs are available out there but all of them have some type of monitoring mechanism that realigns the frames.
                        The issue with that is complexity and you end up with something that is not very reliable.
                        I scratched my head a bit and came up with the cog wheel + micro switch approach. The switch roller rides on the cogs and gets activated when close to the cog tip. If the cogs are too small, then another set of cogs can be designed in parallel just for the switch.
                        The MSP430 drives the stepper until the switch is activated. Upon activation the MSP stops the stepper immediately and triggers the camera. It then waits for a preprogrammed time and activates the stepper again.
                        This should be relatively simple to implement. And the added bonus is that it will work much better than Wolverine with the film that has missing perforations. The cost should also be relatively low.
                        Here is a simple sketch of the idea.
                        Click image for larger version

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                        • #27

                          very ingenious as always Stan.
                          I will think about a specific cogwheel. The idea is very good.
                          I am using 20mm printed support and 16mm F5.6 aico lens.
                          I dismantled everything and I will take the opportunity to check everything by following your advice,
                          I will resume the pages of the forum and your last PDf Manual to put back in the Hawkeye adventure.
                          Thank you again for your always useful suggestions.

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                          • #28
                            Thank you Kamel.
                            20mm spacers with the BUC02 and 16mm lens is close to the lens limit. Here is the capture that I did with the same settings. You can see the corners are getting a bit soft.
                            https://photos.app.goo.gl/jWmKGVsEmEgVYdi19
                            My suggestion is to go with a longer spacing. At least a few mm longer.

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                            • #29
                              For the ultimate result I'm thinking about capstan-driven film drive, with optical sensor reading out the perforation. Once it detects the perf edge the motor stops, triggering the camera shutter release, wait for a preset interval letting the camera finish its job, and move to the next frame.

                              This will largely depends on the precision of the sensor itself. Unless there's a way to precisely detect the perforation's edge the trigger will be too erratic, surely resulting in poor image stability.

                              Nah, this would be too complicated for me anyway. I'd better stick to modified projector mechanics method.
                              My current setup will reliably capture 3mp still image sequence around 2-2.5 fps. This seems to good enough to serve my current need so I'm done with that.

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                              • #30
                                Kamel, I suggest that you mount the lens and camera in your "test rig". That should show where the best distance to focus is with less effort than mounting and dismounting the lens in the Hawkeye.


                                Stan, I think a limit switch actuating off a sprocket wheel is simple and possibly more accurate that a light sensor using film perforations. If the perforations are damaged or if the film is exposed beyond the frame, there is jitter.

                                I've seen some 8mm films where that is true. Probably most commercial prints are clear around the perforations. I have seen films digitised with a "Moviestuff" that show jitter due to undamaged perforation irregularities.

                                So with a real capstan, where the film is compressed against a roller that drives another roller with teeth or highspots to run the capture switch, it could work.

                                One problem that comes to mind might come from film that has stretched or shrunk. I don't know how likely that is, but frames would then have unpredictable spacing.

                                An indirect drive, an encoder on the capstan, controlling the switch motor's speed could be fine tuned for spacing. Or just control a trigger switch based on timing from the speed.

                                I like the concept, I'm just thinking out loud!

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