On-lining time, Help me persuade the Avid heads

[Paul Provost]

you should get better results doing the reconform via sdi, especially with gfx. i think you will get a much sharper picture than trying to uprez the dv footage in the sequence, as long as you have the drive space. media manager is a nightmare by the way. try searching posts here and in fcp forums.
you might want to try leaving everything in dv and outputting via sdi using decklinks dv bridge feature “blackmagic dv – ntsc” easy setup
directly to digibeta. this yeilds pretty amazing results

[Lexerton]

Thanks Paul

I was hoping you wouldn’t say that! I’d love to save the time by not reconforming. Is the media manager really that bad? https://www.kenstone.net/fcp_homepage/basic_onlining_jordan.html suggests that whilst inelegant it does actually work.

I still don’t quite understand why SDI reconform would be better than using the original firewire footage – after all its just cloning the DVCam, right?

If I uprez it to 10bit for effects and colour correction all the processing will be done in 10bit space but surely you can’t make DVCam footage better either way? Or is there a perceptible difference?

Ta

Lex

[Chris Tomberlin]

[lexerton] “Is the media manager really that bad?” YES!

[lexerton] “I still don’t quite understand why SDI reconform would be better than using the original firewire footage – after all its just cloning the DVCam, right?”

I’ve done many tests with this and can confidently say that you well get much better results loading stuff back in via SDI to 10-bit uncompressed than going from DV to uncompressed in the computer – ESPECIALLY in terms of color correction. I’ve done many short films for one client exactly this way. Footage originated on a DVX100 (24p miniDV). We offline at DV, but reload everything via SDI to 10bit uncompressed. I’ve compared the results, the SDI route is better. I think probably because the deck is doint a hardware “upres” versus doing it in software. You can do the test yourself. Load something via firewire, then load the same shot via SDI to 10bit. Blow up both shots if you need to, then A/B the two clips. The 10bit WILL look better, especially in the reds.

[lexerton] “If I uprez it to 10bit for effects and colour correction all the processing will be done in 10bit space but surely you can’t make DVCam footage better either way?”

Again, I think the difference here is hardware versus software conversions. Loading it in via SDI to uncompressed won’t make it better than it was originally, but it will definitely give you better results for color correction. Trust me on this one.

Chris Tomberlin
OutPost Pictures

[Sean Oneil]

Gramme Natress did an extensive test on this subject.

The short answer is, it doesn’t matter – provided you apply the 4:1:1 chroma smoothing filter on the DV footage before bumping it up.

[Lexerton]

I’m supposing that this is what it boils down to –

the tech theory which is that there is no theoretical advantage to SDI reconform as per the big N’s theory (I have the PAL version of his chroma smoother and really rate his products)

the subjective test which is a visual perceptive difference.

the main thing is that I’ll have to test the different outputs on a grade 1 monitor and through an SDI scope with my facilities head.

I’d love to prove him wrong but only cause I’d rather not do a conform.

Don’t suppose anyone would dare point me in the direction of a proven on-lining method that by passes the media manager?

Ta

Lex

[Steve Regian]

With the cost of fast SATA hard drives at very low prices, we just capture 10bit uncompressed to start with and work in a 10bit timeline… no rendering.

Then we just use media manager to consolidate our clips and delete our unused stuff.

I highly recommend the Firmtek SATA boxes and, with 4 drives striped raid 0, we find we have plenty of overhead for all our 10 bit SD projects.

[Sean Oneil]

It’s actually quite simple. DV is 4:1:1. When it’s converted to Uncompressed, it becomes 4:2:2 which causes artifacts. There are two ways to do it. The deck can do it (re-capture using SDI), or the Apple DV softare decoder can do it (conforming). The first method automatically smooths out the chroma for you, which can help. The software method does not – which leaves it more “pure”. However, by applying the 4:1:1 chroma smoothing filter, you can achieve virtually the same thing. So the end result is almost identical to what capturing via SDI would give you.

But I always ask people, if quality is so important, why the heck are you shooting on DV in the first place?

Also, I too use and reccomend the Firmtek products.

[Lexerton]

Good point.

Budget, budget, budget. Here in the UK a vast amount of broadcast is being shot with DSR500/570 cameras.

This show is 13 parts, shooting over a year with 80 rolls already done capturing 10bit off the bat is impractical.

I, too have a 4 drive sata raid but with the sonnet tempo 4+4 which I’m very happy with.

I suppose I’ll just have to test the SDI footage next to the DV with the 4:2:0 smoother.

Believe me I would have loved to shoot this on Digibeta but there just isn’t the money.

ta

Lex

[Sean Oneil]

DV50 is the way to go. Or for even less money, there’s HDV which you can just downconvert.