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Making a video transfer from 16mm A&B rolls
I need to make a videotape from a 16mm film, working from the edited A and B rolls of camera original. (Here is a bit of explanation: The A-roll of a film includes the odd-numbered shots separated by lengths of opaque leader which exactly correspond to the length of the shots on the B-roll; the B-roll includes the even-numbered shots separated by lengths of black leader that exactly correspond to the length of the shots on the A-roll. A print is made by running the A-roll through a printer in contact with a length of raw print stock, which is then rewound, synchronized with the start mark, and run through a second time in contact with the B-roll. Then the print is developed.)
I know that telecine machines create a 29.97fps NTSC tape from the 24fps film by distributing the film’s frames over the tape’s fields in a pattern of alternating 2s and 3s (2:3:2:3). The video house use the A&B rolls to produce two video files, one from the A-roll and one from the B-roll, which I can combine in FCP. The problem is that a given shot in this case may well start with a frame that is made up of one field and image and one field of black. I have no good idea of how to deal with this. Is there a way of separating fields in FCP? I realize that I can deinterlace these problem frames, but chance might give me a deinterlaced frame that is all black. But I’m not sure whether the deinterlacing is a good idea since I won’t be able to re-interlace the shot using a field from the last frame of the outgoing shot.
Another strategy I’ve thought of is to ask the video house to give me two 24p files. In that case there will be a one-to-one correspondence between film and video frames. But I need to be able to make (among other things) an interlaced tape and DVD. Will FCP allow me to copy the finished 24p sequence and paste it into a 29.97i sequence? Will the image quality be compromised?
Finally, I would prefer to work from a DVD100 file as my original so that I can produce versions in both HD and SD DVD. Any pitfalls here?
I’d be grateful for any help.
ALFRED GUZZETTI
Alfred Guzzetti
Mac Pro Quad 2.66GHz 4GB RAM
Intensity Pro card
OS 10.4.9
FCP 6.0 -
7 Replies
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[Alfred Guzzetti] “But I need to be able to make (among other things) an interlaced tape and DVD.”
Tape isn’t a problem since FCP can insert extra fields on playback. For DVD you will need a Standards Conversion plugins by Graeme Nattress.
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Alfred
I used to work on a tv show that would bring me conformed 16mm A and B rolls transfered to Videotape. Then they would bring in opticals that were supposed to be frame per frame as the original. this was before any 3:2 aware transfer technology, so I had to make freeze fields and all that to get it to work. what a pain!
long story short? get the 24 fps files! (23.97) and work at 24 until ready to export, then you can add the nexessary pulldown for 30 fps
did you say you were going to DVD? try a test at making a dvd at 24.
hope this helps
“I like video because its so fast!”
Bob Flood
Greer & Associates, Inc. -
Bob,
The video house did a short test for me at 23.98P using AIC at 1920X1080. This is OK but when I drop it into an HDV 29.97 1080i sequence (as I’ll have to sooner or later in order to get a tape output), the motion is unacceptably jerky because FCP deals with the time-base difference by simply duplicating every 4th frame, even though the playback is set for 2:3:2:3 pulldown. I don’t see an obvious way around this. I may have to settle for a 29.97 transfer and fix the cuts that look bad one at a time.
ALFRED
Alfred Guzzetti
Mac Pro Quad 2.66GHz 4GB RAM
Intensity Pro card
OS 10.4.9
FCP 6.0 -
Alfred
What happens if you keep your sequence at 23.98 and export a native quicktime also at that setting, but then use compressor or cinema tools to add the pulldown? when it comes to any format conversion, compressor usually does a better job than an fcp quicktime conversion.
IF even after you try the above workflow you stil see the repeated fourth frame, double check that everything is indeed 23.98 the transfer, your sequences, and so on, as well as, just for giggles, making sure you are seeing both fields in your monitor. and not a single field, which may only be the 4th
hope this helps
“I like video because its so fast!”
Bob Flood
Greer & Associates, Inc. -
Thanks, Bob. I tried what you suggested, using Compressor. Every 4th frame is still duplicated. The original checks out at 23.98 and the conversion at 29.97. I’m looking at everything on a video monitor as well as the computer monitor; so I’m pretty sure I’m seeing both fields.
Alfred
Alfred Guzzetti
Mac Pro Quad 2.66GHz 4GB RAM
Intensity Pro card
OS 10.4.9
FCP 6.0 -
hey alfred
I know this is frustrating especially because both FCP and Compressor are supposed to do this.
the only way, and I am only thinking out loud here, that you should get this 4th frame repetition is if something is off speed or something is broken
are you running FCP 6.0? or 6.0.3? try upgrading if you havent already
did you trash your preferences?
what happens if you bring the files into compressor directly, and convert them from HDV to DVCPROHD, ProRes, or even Uncompressed but dont change the frame rate, so at least you are dealing with full frame material and not long gop HDV.
I can tell that you seem to be very thorough about all this stuff but, just cuz we are all human, double check everything.
The only other thing i can suggest is to repost your queston rephrased so its get noticed. something like “29.97 to 23.98 doenst pull down correctly”
also, notice that , at the top of the forum, Ron and Walter have started to put together an FAQ. If you open the discussion thread you will find a lot of contributed links. maybe one of those links can help.
good luck, and let us know what happens
“I like video because its so fast!”
Bob Flood
Greer & Associates, Inc. -
Bob,
Thanks for your kind and helpful advice.
I tried again with Compressor, this time going into all the little sub-menus and choosing the “best” settings. The earlier problem may have been that I didn’t set “field dominance” for the 29.97i file. This time I did and the results were fine, pretty much like a test that the video house produced in DVC100 at 29.97i. Processing this material in Compressor took a VERY long time, about one minute for each second of the original file!
ALFRED
Alfred Guzzetti
Mac Pro Quad 2.66GHz 4GB RAM
Intensity Pro card
OS 10.4.9
FCP 6.0
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