View Full Version : Choose 720 vs 1080 on export?


Robert Bobson
August 5th, 2008, 08:07 AM
If cineform converts any camera format (1080i, 720p, 1080p?) into it's intermediary format so I can edit them all together, then when I'm finished editing do I get to decide which format to "output" onto videotape?

If so , then I can shoot my fast action motion scenes in 720p, and my beautiful tableaux scenes in 1080i, and then edit everything together and get the best of both worlds?

Ahh, but then I suppose if I export to 1080i, my fast action motion scenes will still show motion distortion. But at least I'd have a choice at the end as to which format serves the majority of my footage best!

Am I correct is these assumptions?

David Taylor
August 5th, 2008, 09:57 AM
Yes, you can edit footage from multiple cameras, but you need to be careful when mixing 720p and 1080i. Generally we feel interlace should be banned - there is little "good" that comes from interlace.

If you're mixing progressive and interlaced footage, you'll *probably* want to deinterlace your 1080i footage to progressive and edit your project at 720p. We (and others) provide a deinterlace algorithm in HD Link. But if your 720 footage is 24p, then deinterlacing your 1080 footage and also converting to 24p is a difficult conversion.

If you haven't shot your material yet, you might be better off shooting your 720 material at 30p because it is easy to deinterlace 1080i to match.

Anyway, there are a number of decisions to make depending on your source material and your intended output. And yes, we support all the options, but some choices are better than others.

Robert Bobson
August 6th, 2008, 06:16 AM
If we shoot in DVCPRO HD, and then convert using Prospect HD, is it "best" to output back to DVCPRO HD - or would that just depend on the deck we record back onto?

I have a client who wants HD, and he says he wants "the best", even though most people aren't going to know if it's HDV or HD-SRI or DVCPRO HD or whatever.

This may be a bit off topic, but my client is hung up on 1920 x 1080 as opposed to 1440 x 1080. Isn't 1440 x 1080 with the 1.33 PAR really the current "normal" HD format that's mostly being used. everything gets upconverted and downconverted at the viewers monitor anyway??

David Taylor
August 6th, 2008, 09:06 AM
If we shoot in DVCPRO HD, and then convert using Prospect HD, is it "best" to output back to DVCPRO HD - or would that just depend on the deck we record back onto?

I have a client who wants HD, and he says he wants "the best", even though most people aren't going to know if it's HDV or HD-SRI or DVCPRO HD or whatever.

Robert, "the best" (as measured by visual fidelity) is to keep your finished CineForm project as CineForm files. This will offer you the deepest pixel precision and maintains your editing project as it was cut.

That said, that is not the best solution for all workflows. Each project is different, so "best" is a function of what is needed for the next stage. In terms of visual quality DVCPro HD is definitely not best, as its spatial resolution is either 960x720 (720p mode) or 1280x1080 (1080 mode), and its precision is only 8 bits. Once you've edited your project with Prospect HD you will have spatial resolution and bit precision that exceeds DVCPro HD, so you'll be reducing fidelity by going back to DVCPro HD. But if there is a specific requirement to go back to DVCPro HD or a deck in general, then my discussion about resolution and bit depth is irrelevant. So it really is project dependent.

This may be a bit off topic, but my client is hung up on 1920 x 1080 as opposed to 1440 x 1080. Isn't 1440 x 1080 with the 1.33 PAR really the current "normal" HD format that's mostly being used. everything gets upconverted and downconverted at the viewers monitor anyway??
Well remember, DVCPro HD is not 1920x1080 per the discussion above. However, Prospect HD can convert DVCPro HD to square pixel HD (1280x720 or 1920x1080). Once converted you have a traditional HD workflow. Generally this is best, especially if you're mixing footage from other sources. 1440x1080 is an HDV-specific spatial resolution. I wouldn't call HDV "normal" in a professional sense, but it is highest volume for consumer/prosumers by sheer volume of camera shipments.

David Newman
August 6th, 2008, 09:08 AM
DVCPRO-HD is not the best target format, more heavily compressed compared to your CineForm master, don't use it unless that is what you client wants.

Order of perference:

HDV -- 1440x1080
DVCPRO-HD -- 1280x1080
HDCAM -- 1440x1080
D5 -- 1920x1080 10-bit 4:2:2
HDCAM-SR -- 1920x1080 10-bit 4:4:4
CineForm AVI/MOV file 10-bit 4:2:2 or 12-bit 4:4:4

Pixel aspect ratios shouldn't matter, but 1920x1080 is the most convenient.

Robert Bobson
August 7th, 2008, 05:08 AM
I'm trying to pick a format to do this HD project in - it will air on local tv.

I've heard that tv stations compress the video (and I guess the cable television providers do too?)

So I'm wondering if shooting in 1920 x 1080 is going to provide a higher quality picture to the home viewers than shooting HDV.

The project is an infomercial, not a sweeping narritive epic.

any advice?

also, would a 10 second HDV file and a 10 second full 1920 x 1080 HD file be the same file size after being converted into the intermediairy format by Prospect HD?

I'm worried my work station may not be able to handle the load.

thanks!

Graham Hickling
August 7th, 2008, 07:08 AM
>>would a 10 second HDV file and a 10 second full 1920 x 1080 HD file be the same file size after being converted

You have the option of converting your HDV file to either 1440 x 1080 Cineform with non-square pixels, or 1920 x 1080 Cineform with square ones. The latter will be the same size as the file that will result from conversion of your "full HD" footage; the former will be smaller.