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Old 08-27-2007, 12:31 PM   #2
cybertrix
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Join Date: May 2007
Location: Australia
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Hi Sarashlm,

1. There are a few things to consider.

Firstly, the editor who rendered you the "offline": Did they capture the video via SDI in the first place? If so, you may be able to get a relatively high quality (or even untouched) render straight out of Final Cut. I've worked as a colorist in a few situations where the editor has worked with at full broadcast spec for the whole project and rendered out an uncompressed QuickTime for me. I'm not sure, but it could be better quality to run an SDI cable from the Mac to the PC. (due to the QuickTime importer and how it handles YUV vs. RGB... or if it does anything stupid like feed Edius an RGB source - I don't know enough about the QuickTime importer in Edius. At least from DVCPRO HD it seems to look very solid in Edius Broadcast.)

If the offline is in DV (quite likely), then you will need to build a project from an EDL (or AAF?) and capture off the master tapes. I've had a few problems doing this in the past from FCP, and have ended up manually lining up quite a few shots; but EDL compatibility may have improved. If you need to do this, a clever trick is to render the offline from the Mac (to DV format) and put it on the top track in Edius. Then drop a "Difference" keyer onto it and you can turn this track on and off to make sure your online matches your offline. The result (when you play back) should be a black image for the whole film and any differences will show up as "wobbling" outlines.

What format is the film on? DigitalBeta? DVCPRO HD? HDCAM? HDCAM SR? If it is on DVCPRO HD or 50, I'd recommend capture using Firewire to get a DVCPRO based project at CODEC level. (you will need the broadcast version of Edius for this)


2. I have always left audio for my Sound Engineer to deliver. I seem to remember we just used a DAT, but that was Dolby Surround (from Stereo) and not 5.1. The audio was lined up to my TIFF files at the film printing facility. Although I did drop in an AIFF just to preview that the audio matched up. (hopefully someone else can help here for 5.1)


3. You may be able to laser print your film from TIFF rather than DPX. I don't think Procoder 3 supports DPX output, but Edius outputs TIFF 8bit (though Still exporter) and I have used this format to print to film from Edius.

Keep in mind that what you are trying to do from Edius is something quite advanced and usually reserved for a specialist. There are A LOT of tweaks that a professional can make in order to get a better quality print such as setting clever curves, crushing blacks in certain ways, etc.

For instance, you are outputting (probably) from a CIR 601 YUV source or similar HD space... and DPX is an RGB based format using 10bit Log channels. This is quite a conversion! Even when converting to RGB based TIFF, you can end up (potentially) with muddy or washed out blacks on your print if the printing / laser facility was expecting the blacks to be at RGB level 0 (where the YUV level equates to level 16). Plus banding can potentially become more apparent if you convert your color space too many times.

Now, my method (with some tweaking at the printing house) produced a clean print with DVCPRO HD as the source material.

This is how my workflow went:

I graded the video totally ignoring broadcast safe and pushed the levels from the DVCPRO HD P2 rushes so blacks were 0 and whites were hot at just under 255. Now before anyone shoots me for the quantization I've "already" introduced, I must point out that we were pushing the levels around dramatically in the grade anyway, so it made more sense to do the expansion at this point rather then fit it all in CCIR then do an expansion post YUV>RGB conversion. We were using Edius to grade purely because it's fast and real-time - but then again, we all know that don't we?!

After the grade was looking clean (or as clean as you get from DVCPRO) I exported to 8bit TIFF. This is where I was a little unsure - because YUV > RGB produces quite a few quantization errors as far as I know (which can lead to banding and noise to be slightly more noticeable)... Maybe Canopus can make us a 16bit TIFF exporter in the next release :-D I considered going to a YUV uncompressed file and using After Effects to try and export 16bit TIFF files - but our budget didn't stretch. Our client didn't even want to pay for HD at the start!!

Now, when I exported, I did NOT use the aspect correction to convert my resolution back to 1920 x 1080. The machine my film was being "lasered" with was already going to perform a resize and slight crop (apparently). It could work with anamorphic files of various ratios, so I left my TIFF files at the DVCPRO HD standard size. It is better in my experience not to perform multiple resizes.

I opened a few of the TIFF files to check the quality, and considered running a batch smart sharpen on them, but refrained as I didn't want the edges to look too messy. I was told the grain softens the image and adds it's "own quality" anyway.

Once I handed over my harddrive of TIFF files, the operator / tech loaded them into a program and made a few minor adjustments to the overall curves, etc, and showed me some stills on a top end HD monitor. It looked amazing - but you expect that! (there was no sound at this point - the DAT arrived separately) Then that was it. I went home.

The 5 prints of the 30 sec TVC were delivered directly to the agency and I was able to watch one at a local screening a few weeks later. It certainly held up to the previews and looked a LOT better than the obviously SD prints. The blacks were solid and it didn't look too much like video, there was no noticeable artifacting and although the highlights / mids still looked slightly video-like in a few shots, I was quite amazed at the result.

So hopefully this will help you. Most facilities will have a machine that is able to output DPX from whatever format you provide - so I would stick with TIFF which I can tell you works ok. Most important thing is to talk to your printing facility!!! Ask them what formats they can work with. There is little point to spending hours trying to convert 1000's of frames into DPX if the facility can do a better quality job for you.

You may also be able to output your final film back to a tape and give them that. Then they can do all your YUV > 10bit RGB LOG conversion for you.

best of luck,

Chris
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