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#1 Justin Donoghue

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Posted 06 October 2009 - 01:47 PM

Hi
I'm hoping I'm not repeating a previous post on here but I have what appears to be a frame rate problem with my super 8 footage I got transfered recently to mini-dv. I filmed the footage at 25fps (I'm sure of this) and indicated this to the people who tranfered it however the footage seems to me to be running slightly slower than it should. I notice this particularly on the footage of people walking...they don't seem to be walking in real time. I'm wondering was this footage mistakenly transfered @ 18fps? The AVI I've captured from the mini-dv tape is PAL 9I'm in Europe) and showing as 25fps but I assume that's not relevant as if it was mistakenly transfered @ 18fps it would still be seen as a PAL 25fps transfer because "filler" would be applied. Any opinions welcomed. I hope there is not a problem with my camera but it has only recently been serviced and the footage itself I'm very pleased with in terms of exposure and quality.
Thanks!
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#2 Chris Rowe

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Posted 06 October 2009 - 02:24 PM

I do not know how noticeable the difference between 24 and 25 is but maybe they thought it was 24fps when they transferred.

this is just a non-serious thought, but maybe a lot of viewing 18 or something has produced a certain vertigo where now real time appears slower than actual. like driving on the highway for a while and then driving on side roads a little fast because you're used to moving at a higher speed. it does seem very possible that transfer could be incorrect though.
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#3 Colum O Dwyer

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Posted 06 October 2009 - 03:19 PM

I do not know how noticeable the difference between 24 and 25 is but maybe they thought it was 24fps when they transferred.

this is just a non-serious thought, but maybe a lot of viewing 18 or something has produced a certain vertigo where now real time appears slower than actual. like driving on the highway for a while and then driving on side roads a little fast because you're used to moving at a higher speed. it does seem very possible that transfer could be incorrect though.


When I shot my 1st Super-8 about a year ago I noticed something similar.

I figured that because the camera wasn't crystal-synced (& few Super-8 cameras are from my understanding) the frame rate was simply inconsistent and the action seemed to happen at inconsistant speeds after being transferred at 25fps.
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#4 Justin Donoghue

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Posted 06 October 2009 - 03:43 PM

When I shot my 1st Super-8 about a year ago I noticed something similar.

I figured that because the camera wasn't crystal-synced (& few Super-8 cameras are from my understanding) the frame rate was simply inconsistent and the action seemed to happen at inconsistant speeds after being transferred at 25fps.


I would have thought that each frame would be captured individually by the telecine process so it didn't matter what fps the camera was running at (within reason)? Once each frame is captured they are all added together and in this case it seems added at 18fps to give a slowed down effect to what was originally shot at 25fps.
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#5 Tom Jensen

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Posted 06 October 2009 - 03:51 PM

The standard frame rate for super 8 is 18fps. You transfer it at 18fps to get real time. If you shot at 25fps and transfer it at 18fps then the transfer rate is slower than it should be. If you didn't specify the frame rate you shot it at and the transfer frame rate you desired, I can see where they assume it is a straight transfer at 18fps.
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#6 Justin Donoghue

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Posted 06 October 2009 - 04:03 PM

The standard frame rate for super 8 is 18fps. You transfer it at 18fps to get real time. If you shot at 25fps and transfer it at 18fps then the transfer rate is slower than it should be. If you didn't specify the frame rate you shot it at and the transfer frame rate you desired, I can see where they assume it is a straight transfer at 18fps.


Yes I thought as much. I specified that they should transfer @25fps but it looks like they've transfered @18fps hence the slowness.
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#7 Matthew W. Phillips

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Posted 06 October 2009 - 04:18 PM

They must have ignored your request to transfer @ 25fps. If they would have transfered it at 24fps, it is doubtful that you would see that much of a slow down. I don't think it was the camera motor either. Although camera motors vary unless synced, they won't generally vary enough to appear as slow motion. For it to appear as slow motion, your camera motor would actually have to have a frequency spike to cause it to film more frames per second (than 25) and then transferring at a lower speed...this is most doubtful. I would defintely say that this was transferred at <25fps.

Was this a RANK house? I ask because there are some cheap transfer houses that use "real-time" transfers and those only tend to work around the 15 3/4 fps range. There are other rates that they work but they never work flicker free at 24 or 25fps. These are the houses that use real-time workprinters or Goko telecine systems, or even as generic as projecting on a wall and filming it with a camcorder. You can usually tell these places by the fact that they say "No Negative film transfers."
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#8 Justin Donoghue

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Posted 06 October 2009 - 05:16 PM

They must have ignored your request to transfer @ 25fps. If they would have transfered it at 24fps, it is doubtful that you would see that much of a slow down. I don't think it was the camera motor either. Although camera motors vary unless synced, they won't generally vary enough to appear as slow motion. For it to appear as slow motion, your camera motor would actually have to have a frequency spike to cause it to film more frames per second (than 25) and then transferring at a lower speed...this is most doubtful. I would defintely say that this was transferred at <25fps.

Was this a RANK house? I ask because there are some cheap transfer houses that use "real-time" transfers and those only tend to work around the 15 3/4 fps range. There are other rates that they work but they never work flicker free at 24 or 25fps. These are the houses that use real-time workprinters or Goko telecine systems, or even as generic as projecting on a wall and filming it with a camcorder. You can usually tell these places by the fact that they say "No Negative film transfers."


I used the widescreen centre in London. They do negative transfers aswell although it doesn't specify whether they do real time or frame by frame transfers or what system they use, just that it's "professional grade" (grain of salt required perhaps). I should probably just get on to them and see what their opinion is. Thanks for all the feedback.
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#9 Kevin Thomas

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Posted 06 October 2009 - 05:18 PM

Hi
I'm hoping I'm not repeating a previous post on here but I have what appears to be a frame rate problem with my super 8 footage I got transfered recently to mini-dv. I filmed the footage at 25fps (I'm sure of this) and indicated this to the people who tranfered it however the footage seems to me to be running slightly slower than it should. I notice this particularly on the footage of people walking...they don't seem to be walking in real time. I'm wondering was this footage mistakenly transfered @ 18fps? The AVI I've captured from the mini-dv tape is PAL 9I'm in Europe) and showing as 25fps but I assume that's not relevant as if it was mistakenly transfered @ 18fps it would still be seen as a PAL 25fps transfer because "filler" would be applied. Any opinions welcomed. I hope there is not a problem with my camera but it has only recently been serviced and the footage itself I'm very pleased with in terms of exposure and quality.
Thanks!


Hi Justin,

I would suggest you contact the company with your concerns especially as you are pleased with the other aspects of the transfer. If you have used them before I'm sure they will not want to lose your custom, if you are a new one they will be hoping for more. Besides it is not a bad idea to build some sort of relationship with a key supplier of services.
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#10 John Sprung

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Posted 06 October 2009 - 05:22 PM

Can you single-frame thru the video? If so, pick a section with some fairly rapid movement, and see if you get two fields from each film frame. If you get more fields, or blur-betweens, then they've done something other than a straight 25 fps to 25fps transfer.

What's the total run time of the video compared with the total run time of the film? If the video runs considerably longer, then they slowed it down.




-- J.S.
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#11 Kevin Thomas

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Posted 06 October 2009 - 05:28 PM

A final thought.

It's been a long day but can't you work out the frame rate by the duration of the footage?
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