Thanks, Mike.

Yes, I have read Glenn's article. What I'm trying to find out is if the new 32-bit scheme in Vegas 9 obviates the need for some of the color space manipulation Glenn recommends in the article you referenced.

If I'm using Vegas 9's "video" 32-bit colorspace, do I need to add the Computer to Studio RGB (or vice-versa) depending on the output format, or is that all handled automatically now in Vegas 9?

Sorry Brian but I just installed Pro 9 last night and I haven't found the need (yet) to work in 32-bit so you'll have to wait for Glenn to answer your questions.

Mike

I'll have to write a new article for Vegas 9 since things changed. Right now I'm figuring out how it's different.

New article up!
http://www.glennchan.info/articles/vegas/v8color/vegas-9-levels.htm

Hopefully it doesn't have too many mistakes...

The good news is that working with 32-bit in Vegas 9 can be less crazy.

Glenn, I think your articles are confusing because you make no distinction between NTSC and PAL (most of the world). For example, the colour space for PAL DV is RGB 0-255 so "illegal/out-of-range values" are not an issue here.

I do not know if the colour space is the same for HDV, MPEG, AVCHD etc in the US and Europe (rest of the world), but I wish someone can explain possible differences between NTSC- and PAL-land for these formats.

Jøran Toresen
(Norway)

Jøran,

It is my belief that you are currently misinformed about the PAL DV format. While you may have values at 0-255 RGB when dealing with 16-235 Y'CbCr 4:2:0 PAL DV the reasons could be numerous. Including that camcorders can record towards super black and have headroom to shoot over 235 towards super-white. This doesn't mean this is acceptable for broadcast or for release as a consumer product.

RGB would be an interim representation for PAL DV, or a final representation when passed over a SCART/Peritel/Euroconnector in RGB form or decoded by the TV receiver for showing on the display itself. But PAL DV and RGB are separated by at least one layer of processing outside the stated base format of PAL DV.

There are things that are different with PAL, including some which exactly apply to PAL DV in how things differ between PAL/NTSC and PAL/ATSC-HD. Nevertheless, the world is rather a soup of standards and recommendations. Perhaps made worse by attempts to improve and tweak on North American and Japanese formats when they arrive in Europe (etc) later than their cousin formats.:

Probably too many references to be healthy, but I feel that you've had some misguidance and these may go some way to correct those.

Pixel aspect ratio, resolution, cadence etc:
http://en.wikipedia.org/wiki/Standard-definition_television

Timecode and others:
http://www.adamwilt.com/DV-FAQ-editing.html

Option with PAL for 14:9 when broadcasting 4:3 on 16:9 system (popular in the UK and New Zealand if not beyond, could be applied with NTSC/ATSC if widescreen didn't also imply HD which it effectively does in North America):
http://www.cgtantra.com/forums/showthread.php?t=2207

Pedestal (most of which is defined for analog representation of video, rather than sitting inside the PAL DV standard):
http://www.glennchan.info/articles/technical/setup/75IREsetup.html

Chroma matrix:
http://en.wikipedia.org/wiki/Chroma_subsampling

Phosphors in monitoring displays (biased to befit CRT):
http://forums.creativecow.net/archivepost/65/200642

Glenn, I think your articles are confusing because you make no distinction between NTSC and PAL (most of the world). For example, the colour space for PAL DV is RGB 0-255 so "illegal/out-of-range values" are not an issue here.

In this case, whether the format is PAL or NTSC (or from a PAL or NTSC country) doesn't matter.

The colour space for PAL DV is not RGB 0-255. PAL DV uses Y'CbCr color space per Rec. 601, with white level at Y' = 235 and black level at Y' = 16. In Vegas, those Y'CbCr values get decoded to RGB (studio RGB if using the default DV codec), and then later they may be encoded back into Y'CbCr.

"Hopefully it doesn't have too many mistakes..."

I'm somewhat confused by:

"For 32-bit projects, I recommend using the (full range) mode which will disallow a compositing gamma of 1.000 and avoid any wackiness from B above. Optically-correct compositing can be achieved in 2.222 projects by nesting 1.000 projects inside them (see the linear light article for more information)."

I would have thought you meant "video" mode here.
Aside from that excellent and well written.

Now, how do we handle Log DPX to Rec 709?
I *think* I've finally got my head around that but I'd sure like a second opinion.
And thanks for those free PS plugins, I think I'll buy your denoiser as well. How well does it work for grain reduction?

Bob.

Terrific, Glenn! Thanks for the speedy and thorough response.

I primarily work with Cineform 1280x720 files, and sometimes with Vegas DV files. I monitor through an attached DV device to a CRT monitor. My primary output is to Cineform Intermediate, Vegas DV, DVD and mp4.

If I am reading your chart correctly, I should be able to work in 8-bit for rough-cut editing, then switch to 32-bit (video levels) for color correction and final editing, without having to put any levels filters on to convert Studio RGB to Computer RGB. Is this correct?

If so, this may be enough for me to upgrade, as this would simplify things immensely.

I would have thought you meant "video" mode here.
Good catch!!!

If I am reading your chart correctly, I should be able to work in 8-bit for rough-cut editing, then switch to 32-bit (video levels) for color correction and final editing, without having to put any levels filters on to convert Studio RGB to Computer RGB. Is this correct?
Yes. (In the sense that you see the same levels between 8bit and 32bit/video levels... which makes way more sense than Vegas 8.)

Once you are done editing, you may still need to apply levels for different deliverables as mentioned in the article.
e.g. print to tape --> no change
encode to WMV --> nest your project (or render it out to a file) and apply a levels conversion to that

If so, this may be enough for me to upgrade, as this would simplify things immensely.
Yes! One of my pet peeves with Vegas 8 is gone.

And thanks for those free PS plugins, I think I'll buy your denoiser as well. How well does it work for grain reduction?
It will reduce film grain too... as that is also noise. (Use the profile film button.)

For film grain, usually it looks 'nice' if you leave the luma/B&W channel alone (mostly) and just remove the colorfulness of the grain. e.g. mix in original B&W detail = 0.6, mix in original color detail = 0. *I'm of the stance that grain in B&W stocks is acceptable/desirable as it makes the image 'grittier'... it really depends on taste.

It's possible/probable that there are some really evil grainy pictures that my plugin can't handle well.. in which case you should email me and see what I can do about it or ask for a refund if you're unhappy (I issue them right away).

---
For everybody else who has no idea what Bob and I are talking about, my other site is http://www.colormancer.ca/free/

I ran a simple test (8 bit) with the same HDV clip on two tracks in Vegas 9 aligned vertically. I applied Color Corrector Fx Computer RGB to Studio RGB to one track only. The other track was default (computer RGB) . Using track motion and crop I split the image, one half with Studio RGB and the other half none (computer RGB). I measured the bright areas of the Computer RGB half using AE identifying areas in the 250+.. I rendered the timeline to NTSC DVD WS and burned a DVD. I played the DVD with a old Sony DVD Player and looked at the image on a Sony flat screen CRT Vega. The split line in the image was not readily visible until the midtones and highlights. The highlights were significantly better in the default (computer RGB) and dull with a loss of detail in the Studio RGB half. As far as I could see the DVD player/CRT TV was not degrading the image as much as the applying the Studio RGB fx.

Ed B

I applied Color Corrector Fx Computer RGB to Studio RGB to one track only.
Why would you do that?

HDV is MPEG2-based. So you're going from mpeg-2 to mpeg-2. If you're using the default codecs for HDV and DVD/MPEG-2, the levels will be matched since you're going to and from the same codec. You don't need to do anything in that case.
*Unless you prefer to do something about superwhites. Most cameras record illegal values above white level. Some DVD players and TVs clip them off, others don't. But if you want to deal with the superwhites, computer RGB --> studio RGB is not the thing to do.

I applied Color Corrector Fx Computer RGB to Studio RGB to one track only.
Why would you do that?

I wanted to create a split image with computer RGB on one half and studio RGB on the other so I could compare the images on one DVD.

I admit I am a little confused by your descriptions.:) All the video levels I measure on the timeline are 0 - 255. from HDV and DV cameras.

You recommend Suppose you have DV, HDV, and JPEG images in your timeline. For 8-bit projects, I recommend converting everything to studio RGB levels. If I follow this workflow the DVDs looks flat compared to DVDs made from 0 -255 Computer RGB. That is why I made the split image so you could see the difference , Studio RGB vs Computer RGB, on the same DVD. What am I reading incorrectly?

PS: Yes, I use your procedure to remap the superwhites.

Ed B

In an 8-bit project, DV and HDV footage will decode to studio RGB levels (with default codecs). So leave those media alone.

Missed the obvious :) The HDV and DV video are decoded to studio RGB levels and the luminace histogram show timeline levels 0 - 255 because of superwhites not because the videos were decoded to computer RGB.

Ed B

"the luminace histogram show timeline levels 0 - 255 because of superwhites not because the videos were decoded to computer RGB."

Look at the blacks, much better indication of Studio / Computer than the whites. I've never seen footage from a video camera that decodes as Computer. Most go over 100% by 'accident', today some go to 109% by design, depending on camera setup.

Bob.

Bob,

Thanks for the info. I checked all my cameras and they are also over 100% by 'accident'. :) I checked a few commercial SD DVDs and they have illegal white levels so apparently not everyone is applying a broadcast filter.

Ed