FCP offline edit system for Viper/SRW1 project
by derthadams
on
Sep 20, 2007 at 8:32:37 pm
I'm about to shoot a feature film overseas on the Viper, recording to HDCAM-SR 10 bit 4:4:4 in SQ mode (440 Mbps).
The director wants to do the offline edit in FCP in standard def and is asking my advice on workflow. He hasn't purchased the computer or video card yet, so our options are pretty open at this point.
His plan is to ingest directly from the SRW1, using the standard def SDI output on the deck to generate a downconversion on the fly, connecting to the computer via the Blackmagic Decklink SD card.
I know that a lot of productions do a tape-to-tape downconversion first instead of doing it on the fly, but evidently we won't have access to any sort of professional SD-format deck to make actual downconverted tapes. He wants to generate dailies by making DVDs from the FCP clips.
My concerns are:
-What happens to the timecode when using the downconverted signal from the SD-SDI output of the SRW-1? (since the video is changing time bases)
-What operations are necessary in FCP/Cinema Tools to accurately remove the pulldown inserted by the SRW-1? (is it a 3:2 pattern, like a telecine?)
-After pulldown removal in FCP, will the timecode on the new 23.98fps clips match the timecode on the original 23.98fps HDCAM-SR material, so that the exported EDL will be correct in the conform?
I know from my limited post experience that this is potential minefield territory. It would seem to be much simpler to edit in compressed HD using the HD-SDI output from the SRW-1 and an HD video card (at least then there wouldn't be pulldown/timecode issues), but we don't really need HD resolution since it's an offline, and the director wants to save money.
Re: FCP offline edit system for Viper/SRW1 project by Mads Nybo Jorgensen on Sep 20, 2007 at 9:56:23 pm
[derthadams]"and the director wants to save money"
RUN, BABY RUN!!!
Your Director is an idiot, and when he realizes that, he will blame you for not getting him the right advice! In the end you loose, and you then you loose - one more time, you will not win this quest. If you don't have the work-flow sussed, don't do it.
BTW: low budget? overseas? shoot 25fps, down-convert to DV-CAM on set and capture in via fire-wire (second hand DV-CAM PAL deck is cheaper than black magic with hard-disk array). Any other way, get a spade and start digging - 6 foot should do the job nicely ;-)
All the Best
Mads
London, UK
Mac Million Ltd. - HD Production & Editing
Blog: http://blog.myspace.com/bigflopproductions
Re: FCP offline edit system for Viper/SRW1 project by derthadams on Sep 20, 2007 at 10:59:17 pm
Your suggestion to use 25fps capture/PAL downconversion is useful, as it seems like it would allow the use of standard def without changing the frame rate or timecode.
I was under the impression, though, that HD 23.98p-originated shows sometimes use NTSC downconversions for offline editing. How do shows using that workflow manage the timecode differences between the 23.98p original and the 59.94i downconversion?
Re: FCP offline edit system for Viper/SRW1 project by Mads Nybo Jorgensen on Sep 20, 2007 at 11:40:00 pm
[derthadams]"it would allow the use of standard def without changing the frame rate or timecode."
- Absolutely key to a low-cost work-flow. As a DOP, you can shoot what ever time-code you like (Not advisable, straight forward running TC is best. If you do use time-of-day, make sure to put a new tape in the camera in the morning...) If the director asks; it is very common for Low-Cost European features to shoot 25fps, even if it is transferred to film for a 24fps projection.
With the 23.98 you can do a pull-down to NTSC - but you need to know what you're doing. And if its not done correctly, it is going to cost a lot of money.
All the Best
Mads
London, UK
Mac Million Ltd. - HD Production & Editing
Blog: http://blog.myspace.com/bigflopproductions
Re: FCP offline edit system for Viper/SRW1 project by Tim Kolb on Sep 22, 2007 at 3:44:51 am
[Mads Nybo Jorgensen]"With the 23.98 you can do a pull-down to NTSC - but you need to know what you're doing. And if its not done correctly, it is going to cost a lot of money."
Yup...I'm involved with a project peripherally right now with this exact issue.
Re: FCP offline edit system for Viper/SRW1 project by Mike Most on Sep 21, 2007 at 5:39:29 pm
Instead of an SD card, why not get an HD card and ingest using something like DVCProHD? That will avoid the need to change the frame rate or the timecode, and will yield 23.98 fps clips that match the original. The additional storage required will be more than DV25, but less than double. And it will save you a lot of conversion headaches, as Final Cut still doesn't support standard 3:2 removal very well (which is probably why very few people seem to cut in 24fps on Final Cut, even though they should).
One thing I would suggest, though, it that ingesting from what is essentially camera equipment is a dubious practice. The SRW1 is designed to be a field recorder, not an edit system ingest deck. Make sure whomever is in charge of this knows what they're doing.
Re: FCP offline edit system for Viper/SRW1 project by derthadams on Sep 21, 2007 at 6:28:36 pm
Thanks for your response. We're considering using an HD card to avoid the conversion problems you mentioned.
Can any HD card be used to capture in the DVCPRO HD codec on the fly, or do some require you to capture uncompressed, then compress in software?
We were considering using a Power Mac G5 with the Blackmagic Decklink HD Extreme. We would definitely need to transcode on the fly, to eliminate the need for huge disk arrays.
In DVCPRO HD 720p24, can you capture to standard un-RAIDed SATA drives, as in DV?
Re: FCP offline edit system for Viper/SRW1 project by Mike Most on Sep 21, 2007 at 11:31:31 pm
Either the Kona or the Blackmagic cards allow you to capture to DVCProHD in real time. Both have 1080p/24 presets, there is no reason to cross convert to 720 (you would actually need a Kona 3 to do that).
As for capture, you could do that on anything from a large array all the way down to a Firewire drive, although I would recommend at least a Firewire 800 drive. Arrays, even small ones like the portable GRaids, are a bit more reliable, but we've captured many, many hours of 1080p/24 DVCProHD on single Firewire 400 drives without any real problems.
Re: FCP offline edit system for Viper/SRW1 project by derthadams on Sep 25, 2007 at 3:31:54 am
Thanks for your suggestions, Mads and Mike - I've recommended that we purchase our own system and do the offline in compressed HD, but the director is now thinking about using the offline system that our equipment vendor has used for another Viper feature production.
The vendor is an HD production house in India (where we're shooting) that has a Viper, SRW1 (but no SRW5000), Baselight suite, and laser film recorder. Evidently on their last feature, they recorded the Viper at 24fps to the SRW1, downconverted to PAL, and somehow offlined in PAL at 24fps on a FCP system. I haven't heard any details yet on how exactly this was done.
I'm trying to make sense of this - I know that PAL is sometimes run at 24fps for standards conversion purposes ("slow PAL"), but I don't know how this would be implemented in a FCP project.
I'm guessing that they're playing back the 24fps HDCAM-SR tapes at 25fps out of the SRW1, then ingesting this into FCP through the standard def SDI out. I was under the impression, though, that the SRW1 didn't convert TC on the downconversion output.
Seems like with PAL offline, you'd want to shoot at 25fps (as Mads originally suggested). I don't really like the idea of a 4% slowdown on the final output, though.
Is this workflow that they're proposing commonly done in PAL countries? (acquire 24p HD, offline at 24p in PAL)
Re: FCP offline edit system for Viper/SRW1 project by derthadams on Sep 25, 2007 at 7:38:02 am
Sorry, disregard my last post. I've found out that they're using a Blackmagic Decklink HD Pro card connected to the HD-SDI output of the SRW1, and transcoding on the fly to the DV-PAL compression setting (to save storage space) while maintaining a 24fps timebase.
Re: FCP offline edit system for Viper/SRW1 project by Mads Nybo Jorgensen on Sep 25, 2007 at 8:50:35 am
Hey Derth.
[derthadams]"Sorry, disregard my last post. I've found out that they're using a Blackmagic Decklink HD Pro card connected to the HD-SDI output of the SRW1, and transcoding on the fly to the DV-PAL compression setting (to save storage space) while maintaining a 24fps timebase."
Are you sure that you don't want to be 23.97fps..?
And if you're low-budget, I would still strongly recommend that you shoot 25fps.
All the Best
Mads
London, UK
Mac Million Ltd. - HD Production & Editing
Blog: http://blog.myspace.com/bigflopproductions
Re: FCP offline edit system for Viper/SRW1 project by derthadams on Sep 25, 2007 at 6:06:58 pm
I don't think we're going to have any NTSC in our post pipeline - wouldn't that be the only reason to shoot 23.976? We'll be making NTSC deliverables (as well as PAL ones), but can't those be made from a straight 24fps digital master (slow down to 23.976, introduce pulldown frames)?
I'm going to check and see if all of our post audio (composer, ADR, sound editor, mixer) can work off of 24p Quicktimes. If they're expecting PAL videotapes, then I can see where shooting 25fps could make more sense.
Evidently this vendor has done a whole feature at straight 24fps before, and I've heard that it can be done if post audio has the latest ProTools, etc.
I'm not taking anything for granted, though. We want to establish all these details while we're still in preproduction, because I know it can cause endless headaches if they aren't done just so.
Re: FCP offline edit system for Viper/SRW1 project by Mads Nybo Jorgensen on Sep 26, 2007 at 12:59:03 am
Dear Derth.
[derthadams]"Evidently this vendor has done a whole feature at straight 24fps before, and I've heard that it can be done if post audio has the latest ProTools, etc."
Have this vendor only done one feature before?
And have you locked them to a budget/buy-out?
If so, go for it!
If not, good luck.
All the Best
Mads
London, UK
Mac Million Ltd. - HD Production & Editing
Blog: http://blog.myspace.com/bigflopproductions
