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Uncompressed HD


DOsborne

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I've searched high and low and can't seem to find data about how large an uncompressed HD file is. I feel like I've seen something about it in a previous thread but anyways my question is this:

 

Shoot dvcpro hd, edit with FCP, and then move the edited sequence into a new uncompressed timeline to apply and render some mild color correction type stuff and output an uncompressed file for archiving, possible film out, whatever. Does this make sense? How large is an uncompressed HD file?

 

I'd rather not go the route of $2 billion RAID and 300,000 rpm SCSI devices as I'm not editing with uncompressed files that need to be readily played back/scrubbed through, just outputted and saved. I'm looking to buy a new hard drive along the lines of a serial ATA 350-400GB drive with less than 8 ms seek time, is this enough? My "film" is going to be about 25 minutes long and the shooting ratio won't be insanely high.

 

Thank you for your feedback!

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I've searched high and low and can't seem to find data about how large an uncompressed HD file is. I feel like I've seen something about it in a previous thread but anyways my question is this:

 

Shoot dvcpro hd, edit with FCP, and then move the edited sequence into a new uncompressed timeline to apply and render some mild color correction type stuff and output an uncompressed file for archiving, possible film out, whatever. Does this make sense? How large is an uncompressed HD file?

 

I'd rather not go the route of $2 billion RAID and 300,000 rpm SCSI devices as I'm not editing with uncompressed files that need to be readily played back/scrubbed through, just outputted and saved. I'm looking to buy a new hard drive along the lines of a serial ATA 350-400GB drive with less than 8 ms seek time, is this enough? My "film" is going to be about 25 minutes long and the shooting ratio won't be insanely high.

 

Thank you for your feedback!

 

Go to:

 

http://tinyurl.com/a3buv (microsoft.com)

 

and you'll find good definitions of different video sizes. If you scroll down on that page you'll find all the numbers you can eat.

 

Actually, looking at that page now I can see that uncompressed 4:4:4 is not in there, but let's just say that it's a lot. Probably more than you can eat.

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Hi,

 

Uncompressed HD requires anything up to about 200Mbytes/sec; usually, an eight-drive RAID will do it given certain other factors.

 

However, what exactly do you want to do with this HD stream once you have it on a hard disk? If your only interest is in getting it filmed out or taking it to a facility to have it put on HD tape, then you don't need to be able to do it in real time.

 

Phil

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A multidrive RAID is overkill for your use (unless you need the space). A single 400gb drive will hold several hours worth of DVCPro HD, and will give you all the speed you need for editing. If you want to color correct uncompressed, you're better off leaving that to a reputable post house.

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Hi, editing in native HDPRO HD for an offline and bumping up to an uncompressed sequence for online finishing is a good idea as you mention. You could use media manager to export the selects and generate the new uncompressed sequence. A G5 running FCP 5 with lets say a Firewire 800 Raid (Lacie 1 TB big disk or similar) is more than capable of playing back uncompressed 720P material in 8 and 10 bit. This is great since 720P doesn't require an expensive SCSI or Fibre Raid like for 1080. The HDPRO HD 720P codec at 24fps is around 4.8 megabytes. 720P at 24 fps uncompressed is under 80 megabytes. An also interesting note, HDCAM transport records 1440x1080 and HDPRO HD is 960x720, so neither formats record at full HD res to begin with. The HDPRO HD codec at 60 frames is 14.8 megabytes (DV100). Its double of DVCPRO 50 (DV50) at 7.2 megabytes. I wish HDPRO HD had a native 720P 24 frame mode, the transport always records at 60 frames wasting so much data.

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I've searched high and low and can't seem to find data about how large an uncompressed HD file is. I feel like I've seen something about it in a previous thread but anyways my question is this:

 

Shoot dvcpro hd, edit with FCP, and then move the edited sequence into a new uncompressed timeline to apply and render some mild color correction type stuff and output an uncompressed file for archiving, possible film out, whatever. Does this make sense? How large is an uncompressed HD file?

 

I'd rather not go the route of $2 billion RAID and 300,000 rpm SCSI devices as I'm not editing with uncompressed files that need to be readily played back/scrubbed through, just outputted and saved. I'm looking to buy a new hard drive along the lines of a serial ATA 350-400GB drive with less than 8 ms seek time, is this enough? My "film" is going to be about 25 minutes long and the shooting ratio won't be insanely high.

 

Thank you for your feedback!

 

 

An uncompressed 10 bit 1920 x 1080 file, running at 23.98 is 478.05 gig per hour. Other than a 2k scan this is as good as it is going to get. I recommend that you get your film transfered at this res and then you can down res it to DVCPRo HD to edit with. The DVCPro HD as you probably well know, doesn't require a RAID to work with. The uncompressed HD will. As stated before, a eight drive RAID of SATA II running in RAID 5 will do it. RAID 0 ,of course will work, but you have no parity in case of drive failure. SATA II has enought speed with an 8 drive RAID to get uncompressed HD on RAID 5. Hope this helps. Good luck

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It is very helpful to grade with real-time playback because you need to see how your grades work across cuts in the scenes and in-between scenes. Having said that, as long as you're not using a ridiculous amount of compression, your grade decisions should translate from your compressed timeline to your uncompressed conform if you apply the same settings per shot.

 

FCP colour grading is a little course though. It doesn't have anywhere near the fine control that a fully evolved grading system has. So if you have the budget then dgoulder's idea of rendering out uncompressed and getting a professional grade will give you more options.

 

 

David Cox

Baraka Post Production Ltd

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FCP colour grading is a little course though. It doesn't have anywhere near the fine control that a fully evolved grading system has. So if you have the budget then dgoulder's idea of rendering out uncompressed and getting a professional grade will give you more options.

Baraka Post Production Ltd

 

That is exactly what I'm thinking; shoot with the HVX, edit with the files from the p2 card (dvcpro hd), then output an uncompressed file for really the sole puspose as mentioned above by dgoulder and davidcox, to move it (the media) either to a post house color grading facility and/or film out place, and also to put away as a backup file of the completed picture.

 

So I'm NOT editing with 4:4:4 10 bit files, it's just what I want to end up with, if that makes sense. I know that the "uncompressed file" that I'd be producing would never look any better than the DVCPRO codec upon which it was originated but it would be lame to reapply the DVCPRO HD codec again to the final output right?

 

I don't want to expose my dear little project to that codec more than once(in the camera).

 

Thank you to all.

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...it would be lame to reapply the DVCPRO HD codec again to the final output right?

 

Correct - if you colour correct then the compressors effectively have to start over and compress again, because colour correction will upset the compression footprint. If you don't colour correct, I would hope that the material is not compressed again, either because FCP won't recompress it or because the compression algorithm will not see the need to recompress. Both digi-beta and HD-Cam compressors are fairly ?intelligent? this way, in that material compressed once does not get recompressed on each subsequent record, provided the material is unaltered.

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DOsborne,

I actually have gone through this exact workflow. I shot super16mm and had it transferred at Bono labs to DVCPro HD. The video footage therefore being exactly the same as the HVX-200. I did sort of an offline edit in Final Cut with the DVCPro HD footage. I then went into aftereffects and using the origanal master video file i recieved from bono, went though, clip by clip, and color corrected as an 8-Bit Blackmagic uncompressed codec. I took those files into final cut pro and did an "online" with the color corrected. Below are stills from before/after.

The question now of course is, was that extra step worth it? I think so, but the other replies on this topic might have better information.

Steve

 

http://img128.imageshack.us/img128/3188/2abefore6yv.jpg

http://img128.imageshack.us/img128/2623/2aafter3ca.jpg

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  • 2 weeks later...

In what way did you go into aftereffects. Did you export the timeline into a qt or can you open the fcp file in after effects. Sorry if this is a stupid question, I haven't got the chance to work with after effects that much. How did you make it uncompressed in after effects. Also could you do the same thing with combustion.

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  • 3 weeks later...

Bradley,

I haven't looked at this topic in a while, hope i haven't taken too long getting back. The footage that i had transferred at the lab came to me as a single 11 minute quicktime file (i shot 1 roll of 16mm film) that was compressed using DVCprod HD running and 23.98 frames per second. I brought that clip into FCP, and set my sequence settings to accuretly refeclt that clip. I then cut up the clip for editing purposes, and cut the picture together. Once that was done, i went into aftereffects, and imported the origanal quicktime file. Because of the DVCpro HD compression, the file is actually a 1280 x 1080 file, but the compression "expands" it to full 1920 x 1080. So in FCP, my original offline cut sequence was actually set to 1280 x 1080 etc. In after effects, i wanted native 1920 x 1080, (for ease of export to Maya for VFX). I made my composition set to 1920 x 1080, 23.98 fps, square pixels.

 

So what i now had was the full original DVCpro HD file in aftereffects, reading as a 1920 x 1080 clip.

 

I did frame sequence exports to maya to complete the CG, and did all the compositing.

 

Then, i using my FCP offline cut as a reference, i went through that original file in after effects, did the color correction per shot as neccasary, and exported each shot individually. This is the step where the video became "uncompressed." I exported each clip as a Blackmagic Codec 8-bit uncompressed quicktime movie, again running 1920 x 1080. Once i had exported all my shots as individual movie files, i then went into FCP and opened a new sequence to use as my online.

 

This new sequence settings were now 1920 x 1080, square pixels, running 23.98 fps. I conformed the color corrected shots against the offline, and had my finished online master. From there i can down rez to whatever file format, and resolution i please.

 

some notes:

as mentioned above, the DVCpro HD codec is natively 1280 x 1080. The compressor expands this resolution to appear as a true 16 x 9 image. Which is all fine and dandy for watching the footage as a quicktime movie, and for editing in FCP. the reason i went into after effects and changed the resoluction to actually be 1920 x 1080, is because i needed to export image sequences of the live action plates to use in the Maya 3d animation program. Exporting image sequences direct from my offline sequence in FCP resulted in images that had a 1280 x 1080 resolution and were squished. Because those were an image sequence, and did not use the DVCpro HD codec, they would not unsqueeze themselves. Of course i could change settings in maya to fix that...but it caused many problems due my infancy with using maya. being able to have actual 1920x1080 images was, for me, key.

 

hope this helped

cheers

 

Steve

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