I just finished a project that was shot in HD. I need to pass it off to a colleague who will be doing some color corrdctions and maybe qdding some affects. What the best way for me to submit it to him and receive it back so that therews no loss in quality. Should I simply expoert to a mini dv that he can upload to his NLE and then have him do the same when he gives it back to me?

When you say export to MiniDV, I assume you mean as HDV. That will certainly result in image quality degradation. HDV is MPEG-2 at 24Mbps - fine for final delivery of HD content to viewers, but not exactly high quality encoding for use as an intermediate file when editing. It's barely adequate for HD acquisition - and the days of HDV being used as a professional video acquisition format are probably numbered. AVCHD compression image quality blows away HDV, at the same bitrate, and when mainstream CPU power can handle AVCHD with ease, and software support is robust, that should be the knockout punch for HDV.

If you want absolutely no loss of image quality whatsoever, then you need to send the source uncompressed or encoded with a lossless codec, but to do so would involve huge files. For a project of any size at all, you would have to send it on at least a large hard drive (or multiple hard drives if it's a big project).

Usually, the most practical solution is to send the source encoded with a "visually lossless" codec. What that means is that a "lossy" compression method is used, but not compressing so hard as to degrade the image as perceived by the human eye, even after multiple generations of re-compression. The resulting files are much smaller than with uncompressed files, or files generated using lossless compression, but much bigger than HDV files.

You really need to talk with your colleague, and find out what formats he can work with, before you can determine the best way to send your source to him. It's really pointless to try making a decision without knowing what formats he can handle.

You didn't even mention what platform you are working on, PC or Mac, nor what platform your colleague works on, so offering suggestions at this point would be like target shooting while blindfolded. How far away is your colleague? Accross the street, or on the other side of the planet, or somewhere in-between?

Robert:

The final product is 1.5 hours long. He is local so I could certanly hand deliver my project. When I say "export to tape", I mean simply using the "print to tape" feature. The hd product is stored in my NLE (Pinnacale) it will be delivered to someone that is using final cut. Once he makes the changes, he will give the prject back to me where aI will once again upload it tp Pinnacle. I was under the impression that if we both simply use the "print to tape" feature, that there would be no loss in quality. Is this correct? I should also mention that the final product will be printed to a dvd even though the footage is hd. I am working on a pc and he is working on a mac.

"Print to tape" is going to encode the file as HDV (it's the only format that is standard for putting HD video on a MiniDV tape), which again, is MPEG-2 at 24Mbps. If the output, after your editing, were to be saved losslessly, it would fill a whole bunch of tapes. Uncompressed HD video runs into the gigabits per second, not megabits per second.

Seeing as you are on a PC and your friend is on a Mac, that can make things a bit difficult. HDV may actually be the most practical way to transfer the footage between the two of you. Somehow, I've got doubts that you both have Cineform's codec installed on your systems! Is your friend using FCP or express?

RObert he has the Final Cut Studio. He says he has all the options that come with it. Seems strange that print to tpae doesnt give me the exact same quailty that was used when my hd camera captured the footage in the first place.

<walks with cane and sits in rocker>

Back in the old days, there was this thing called 'generation loss'. Any time you dubbed from tape to tape, you could expect some loss. Not bad at all with 1", not real bad with BetacamSP, pretty horrible with 3/4" or god forbid VHS. The one thing you could do is make your first move to a higher quality format--acquire on, say, Hi8 and dub to Beta or 1" for editing. You'll keep more of your original quality.

Digitial is kinda the same way. Ya got yr acquisition codecs and yr production codecs. The acquistion codecs are lossy. Take a real high quality source (from the camera) and stuff it onto tape or a memory card. You lose a pretty good deal of information in the bargain. But you also retain a heck of a lot too.

Yes, modern computers ARE capable of editing long GOP MPEG (HDV) or AVC but every time you decompress and recompress, you are going to take a quality hit. How much depends on exactly what you are doing and what you are doing it with (all codecs, even of the same type, are not created equal).

By using Cineform (or other Digital Intermediate codec), its like moving to a higher quality tape format. You get to manipulate the data much more before noticable quality loss.

"Get to the point, old man!"

If you are talking about color correction, I assume this project means something to you (financially or otherwise). Dumping to HDV would kinda be like shooting BetaSP, editing 1" and then going to back to BetaSP for color correction. Will it work? Sure. Will the quality be acceptable? Maybe.

Finding a high quality format that you can both use would be a much better way to go.

Andy, thanks for the input. Although helpful, i'm still not sure of the best way to hanlde the situation. I will go over to the cineform website to see if that helps. Thanks for your input.

If you both installed Cineform's codec (it's available on both PC and Mac platforms now), you'd have an excellent way to transfer the footage without inducing any visually perceived image quality degradation, as you assuredly would get from re-compressing at least a couple times with MPEG-2 (HDV) encoding, which at 24Mbps is considerably lossy.

You indeed do get the same "quality" (or lack thereof), exporting back to tape, as you got when the camera took that first whack at knocking down the quality of the virgin (uncompressed) images coming from the imaging chips. That's the problem!

Andy's sort of analogy is a good one. HDV basically is the VHS of hi-def, in the digital realm. First generation might be okay for viewing, but dub it a few times (keep clobbering it with HDV compression over and over) and you wind up with oatmeal for a picture.

I wouldn't lump HDV and AVCHD together though. 24Mbps AVCHD offers a considerable advantage, in preserving image quality, over 24Mbps HDV. It's quite visually apparent. I just got a HMC40 a couple months ago. The HMC40 may struggle more in dim lighting, but with adequate lighting, the improvement in compression performance (image quality per recorded bit), compared to my FX1 or XH-A1, is unmistakable.

I wouldn't lump HDV and AVCHD together though.

They are both acqusition codecs--not designed to be edited. Yes, at the same bit rate, AVC is much higher quality and it will work great as a delivery codec but it really shouldn't be used as a production codec.

Can I still use Cineform even though the initial project is completed. I was under the impression that you had to capture the project with Cineform. Is this not correct? I should also say that there are only a few scenes that he will be color correcting. Also maybe a little rotoscoping.

Converting to Cineform, to send to your friend, and if he uses Cineform to re-encode after color correction, will prevent further visual degradation.

They are both acqusition codecs--not designed to be edited. Yes, at the same bit rate, AVC is much higher quality and it will work great as a delivery codec but it really shouldn't be used as a production codec.

With a good encoder, if you crank the settings for quality (really wide motion search, huge GOPS, lots of reference frames, etc. - which will bog down even a high power computer) AVC at 24Mbps will survive a few generations of encoding just far and away better than HDV.

What makes AVC (or MPEG-2 at high bitrates) less than ideal as a production codec, is speed, far more than quality, issues. Crank up the bitrate and encoding settings, and you can get visually lossless encoding, but it's not practical for editing purposes, since playback on the timline will be sluggish at best (unless you build some gazillion core super computer) and you'll be spending most the day waiting on renders.

Cineform and Canopus HQ are ideal, because the quality is great, and performance is fast, although the intermediate files are much larger.

Why can't you just export the files as QuickTime files and transfer it via DVD, or for less compression use a portable hard drive? Is the loss that great. What is the project. Does it warrant 1:1 compression?

After doing some testing over the weekend, it seems that I can simply export my project as an MPEG2 file, and then he can export it the same way after working on it. I was not able to notice any visable difference with this approach. There does not seem to be that same type of compression when creating a MPEG-2 file as oposed to buring an actual dvd. Is this indeed a lossless process? Gordan, I guess I could export that same MPEG2 file to a hard drive as oposed to a dvd, but i'm not sure how much of a difference it will be as it relates to clarity. Anyone have any addittional thoughts on all of this?

You can crunch video with MPEG2 soft or hard. Lots of options available; lots of parameters to tweak. And even then, all mpeg codecs are not created equal.

But you need to learn about GOPs and bitrates. Whatever preset you are using is probably going to be set at long-GOP (anything greater than I-frame) and a bitrate suitable for DVD. Dunno what options yr software has or how customizable the output options are. And sorry, my knowledge is more general than specific as to what bitrate would be advisable.

As to visual loss, you want to stay far away from it. You want to retain as much quality as you possibly can (see post on generation loss). By definition, MPEG is a lossy codec. I'd classify Cineform/Canopus HQ/Prores as less-lossy. See Codec - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Codec#Compression_quality)

Also, since you're goal is color correction, the codec color space is very important. Generic (DVD) MPEG is a limited color format. Greater color encoding is part of the MPEG spec but may not be available with the codec you are using.

How about this: export a short section with your MPEG2 settings and the same with, say, uncompressed if it is an option. Bring it to the mac, mess with it and then bring it back to your pc. And then go ahead and downconvert and burn to a DVD and see what the final result is. Really no substitute for trial and error.

After doing some testing over the weekend, it seems that I can simply export my project as an MPEG2 file, and then he can export it the same way after working on it. I was not able to notice any visable difference with this approach. There does not seem to be that same type of compression when creating a MPEG-2 file as oposed to buring an actual dvd. Is this indeed a lossless process? Gordan, I guess I could export that same MPEG2 file to a hard drive as oposed to a dvd, but i'm not sure how much of a difference it will be as it relates to clarity. Anyone have any addittional thoughts on all of this?

MPEG-2 is "lossy" compression, but if you crank the bitrate high enough, you can get "visually lossless" quality. Go to 50Mbps (long GOP) or 150Mbps (I-frame only), and you really should be fine.

Since both of you are FCP users why not copy a scratch disc and your video file project onto an external HDD and send it off to your friend? You can also export it in ProRes 422, which has to be done anyway to use Color in FCS.

Neither is using FCP. One's on a PC with Pinnacle and the other is on a Mac with Final Cut Studio. Maybe Final Cut Studio is a suite of apps that includes FCP? I dunno. Haven't touched a Mac in decades.