Jitter on 8mm capture

[griffbo]

Hi,

I've been capturing and converting some old Regular 8 cine film. I'm capturing using a Moviestuff Retro-8 unit and saving each frame as a TIF image.

For most of the captures I'm getting a clean frame but occasionally I get some frames that are showing part of the previous or next frame which, when run, shows jittering of the picture.

I'm not sure whether this has been caused by the original cine camera or is a result of the frame-by-frame capture. I have repeated the same scene capture more than once and it is the same on each which makes me believe it's part of the original film.

If it is part of the original film does anybody have any suggestions to fix this using avisynth. I can't imagine it will be easy as you can't necessarily rely on previous frames to determine stabilisation.

For the majority of the film transfer it is smooth and I have been using John Meyer's script which contains normal stabilisation and this is working well. It's only on extreme cases (as in the clip linked to below) where it obviously can't handle it.

Any help would be appreciated.

https://vimeo.com/666272481

[johnmeyer]

Can you load that section of film into the Retro and watch it as it plays? Since the Retro doesn't use claws and pulldown, a loss of loop is unlikely. However, perhaps there is something going on with the timing of the capture.

Having said that, I have definitely seen film which "lost its loop" in the camera, when the film was exposed, and the jumps were "baked in". I was able to fully restore the jumps by using a macro in Sony Vegas (my NLE) to replace each jump with a duplicate. I then fed that into an AVISynth script which used MVTools2 inside of my version of Mugfunky's "Filldrops" script which detects duplicates and replaces them with a motion-estimated frame. You can see the results here:

https://www.youtube.com/watch?v=uzMFodrGHDs

I kick myself every time I post that because I should have used a clip ten seconds later when the truck drives away. The film still had a few jumps at that point and it is far more impressive to see the fix when the truck is moving. I assure you that the results were just as good.

[griffbo]

I guess the problem I have is that I have continuous dropped frames so replacing the dropped frame with a previous frame won't work.

Here's what I mean based on the clip above. Here are 5 contiguous frames and you can see that they've all dropped:

[johnmeyer]

Once you have more than two frames in a row that are dropped or unsalvageable, you are pretty much out of luck because the gaps are going to be too large to fix. After all, how can anything predict motion more than a few milliseconds into the future?

You can try cutting into short scenes, although that may give you more jump cuts than you want to live with. You can also change the speed of the motion of the good parts in order to make the jump cuts less noticeable.

[stephen22]

I think the occasional framejump is one of the charms of 8mm. Enjoy it! Flaunt it!