VideoHelp Forum
+ Reply to Thread
Results 1 to 9 of 9
Thread
  1. Ran into an odd issue. I have a sound super 8 projector that does not allow variable speed. It only has 18 or 24 frames speed selection. I also have an app on the iphone (iphone 5- kinomatic) that allows you to shoot video in 24, 25, 30, 48, 50, and 60 frames (Progressive).

    Technically projecting a film in 24 and then setting the phone to shoot in 24 should sync them up to remove (or virtually remove) any scrolling black bars or flicker from the difference in frame rates. However this did not work. It was only when I set this app to record at 60 frames did the black bars and flicker literally go away syncing the phone with the projector.

    I was wondering why I had to go to 60 frames in order for them to sync? What am I missing here?
    Quote Quote  
  2. Member DB83's Avatar
    Join Date
    Jul 2007
    Location
    United Kingdom
    Search Comp PM
    Been a long time since I did super8 captures - I used a mirror box and fed a camera feed into the capture device.

    However, as far as I recall, capturing silent film (18 fps) at 25 fps still produced flicker. So not really different to what you were seeing.

    Methinks you are simply confusing a film scanner that captures an entire frame effectively as a still. There will always be some flicker from a movie projector although the human eye can adjust for it.

    Just my thoughts.
    Quote Quote  
  3. Originally Posted by mazinz View Post
    Technically projecting a film in 24 and then setting the phone to shoot in 24 should sync them up to remove (or virtually remove) any scrolling black bars or flicker from the difference in frame rates.
    No, the phase as well as the rate much match. And even if both match, they will slowly drift out of sync unless they are driven off the same clock.
    Quote Quote  
  4. Originally Posted by jagabo View Post
    Originally Posted by mazinz View Post
    Technically projecting a film in 24 and then setting the phone to shoot in 24 should sync them up to remove (or virtually remove) any scrolling black bars or flicker from the difference in frame rates.
    No, the phase as well as the rate much match. And even if both match, they will slowly drift out of sync unless they are driven off the same clock.
    Well that makes some sense, but to set it to 60 to even get a close sync was a bit crazy. If I used my old Hi-8 camera I would get the usual flicker, but never had the thick black scrolling bars that I get when using my iphone. I saw one thread on here where someone encountered the same type of bars and near impossible to remove them.

    on the plus side my longest sound film runs about 20 mins, so I can work with it.
    Quote Quote  
  5. I do film transfers for a living, and started out doing transfers the simple way, namely just photographing the projected film on the screen. To cut to the chase, this doesn't work, and the reason has nothing to do with whether you can vary the speed of your projector, or not. And, it has nothing to do with what fps you can choose on your camcorder. The problem is that the camcorder and the projector will never be at the exact same speed, or at the exact submultiple of the other device's speed. Therefore, you will always get beats (noise bars) and other problems.

    Even worse, you will get massive flicker because the projector shutter closes at least once for each frame (as the film is pulled down to the next frame) and, for most projectors, the shutter closes two more times for each frame in order to increase the flicker rate so that the audience doesn't perceive the flicker and therefore get headaches. The problem is that as the camcorder and projector drift with respect to each others' speeds, one video frame may contain two shutter closures, making the exposure for that frame darker, and the next frame may only have one shutter closure. Worse, some video frames will contain a blend of two adjacent film frames.

    It is a mess.

    The only way to get a decent capture is to use a system which guarantees "frame accurate" transfer, where you get exactly one frame from the film onto one video frame. You can then adjust the speed of video playback to match the original film speed, either by changing the playback speed of the video or, for devices which require fixed frame rates (like DVD or NTSC TV), by adding pulldown frames.
    Quote Quote  
  6. Member
    Join Date
    Aug 2010
    Location
    San Francisco, California
    Search PM
    Yeah, frame-by-frame scanner is the way to go. Another benefit is that you can compile a video to play at the proper camera speed instead of being forced into 24 or 18 fps. Sped-up jerky motion is cute but it's an artifact if it wasn't intended by the photographer. I have used a silent scanner in combination with a sound projector: make a DV recording of the audio with reference shot of the screen, then conform it to the scanned video. The speed is always different and changing, so you have to stretch/squeeze the audio section-by-section.
    Quote Quote  
  7. Lots of good information here.
    Its always a pain in the ass and the equipment I want to do this properly cost a small fortune. I also do not have a dslr (just an iphone) because some of them do have a shutter and frame adjust to truly sync up (seen some examples of it and they were flawless in terms of no flicker or anything of that sort, they also cost a good $3000, so thats that). The 60 framerate I mentioned did have minimal non headache inducing flicker and sometimes it looked properly synced with no flicker, and that was from a handheld test. I can work with flicker on the pc but those black bars that I mentioned previously I could not

    JVRaines,
    I originally used my Hammacher super 8 scanner (will scan the film but not the sound) and a dvd recorder to later record the audio from the projector and yes the audio goes off sync. I know I can take a look at it in Vegas just have not gotten around to it and my ihpone records a better pic than the quality the scanner provides which is why I was curious about the framerate which started this thread. Everything is just an annoying hassle. You get used to it after a while but annoying none the less
    Quote Quote  
  8. Member
    Join Date
    Aug 2010
    Location
    San Francisco, California
    Search PM
    Yeah, too bad Roger's RetroScan has become so expensive (closing in on $5,000 now). It does a great job for the price but the price is still pretty high.
    Quote Quote  
  9. Originally Posted by JVRaines View Post
    Yeah, too bad Roger's RetroScan has become so expensive (closing in on $5,000 now). It does a great job for the price but the price is still pretty high.
    Ahh I remember seeing retro scan a number of years ago. Always out of my price range (timing). On a plus side the one true photo place sort of close by either has one of these machines or something that looked exactly like it, and at least I know if I brought my films to them for another transfer what type of method is being used and how it will look.
    Quote Quote  



Similar Threads

Visit our sponsor! Try DVDFab and backup Blu-rays!