Which "standard" NTSC color bars should be used?

addavis wrote on 3/7/2004, 12:20 PM
I am trying to calibrate my NTSC monitor and have discovered a wide range of values in recommended color bar images. Specifically the "Pluge" is all over the place. The dark grey rectangle, that is generated in VV4, shows RGB values of 41-41-41; however, it is my understanding that SMPTE NTSC bars have this value at 24-24-24. I have seen a variety of web pages offering their own "standard" bars with this grey at 10-10-10 or 12-12-12 - and other values.

Comments

Jay Gladwell wrote on 3/7/2004, 4:59 PM
Try this:

J--
addavis wrote on 3/7/2004, 7:26 PM
Thanks for the reply and the link. The linked webpage uses 24-24-24 for the dark grey in the Pluge and Vegas uses 41-41-41. I was under the impression that 24-24-24 is correct, but why would Vegas use different values? Of course, it makes a significant difference in the brightness level of the monitor - approx 7.5%.
rmack350 wrote on 3/7/2004, 11:31 PM
When I compare bars from the camera to the smpte bars vegas provides, they both hit the same marks on the waveform and vector scopes. So either they're both right, or they're both wrong.

Rob Mack
farss wrote on 3/8/2004, 12:56 AM
Know i know VERY little about this or NTSC but 7.5% sets off an alarm, might it have something to do with the 7.5 IRE setup?

I seem to recall that when you use the scopes you need to tell them if you're using setup or not.
craftech wrote on 3/8/2004, 4:07 AM
The pluge bars on the SMPTE picture from that website are nearly impossible to work with. You certainly can't print it and have it come out correctly either. You can buy them for use with your camera, but many cameras have the bars built in. The best bet is to buy a DVD to set up the monitor. On those, you will have lots of different tests which will help more than the SMPTE chart. Two examples are:

Avia Guide to Home Theater by Ovation Software
or:
DVD Home Theater Setup Disc (Silver Edition) by Discwasher Digital

Once "properly" calibrated you should probably increase the brightness and contrast somewhat if you plan to sell the videos because all televisions come with the brightness and contrast set incorrectly (according to "standards").
Properly calibrated monitors are much darker than the average TV which is what your clients will watch the videos on. You need to strike a balance. That is why I never recommend spending a lot of money on an expensive monitor and recommend a good TV instead, but that is a really lengthy discussion which has been covered enough times on the forum.

http://mediasoftware.sonypictures.com/Forums/ShowMessage.asp?MessageID=240098&Replies=56&Page=9

It's up to 56 replies now.

Get one of the DVD's. They will help. Try Amazon.com or Parts Express.

John
Jay Gladwell wrote on 3/8/2004, 5:01 AM
Craftech, what SMPTE picture and web site are you referring to?

If you're referring to http://www.greatdv.com/video/smptebars.htm I posted, you're not supposed to use the picture of the color bars on the site! That's simply a page graphic!

J--
craftech wrote on 3/8/2004, 5:18 AM
That would explain it. Thanks.

I still like my two DVD's the best though. BillyBoy has the Avia DVD as well.

John
addavis wrote on 3/8/2004, 9:23 AM
Actually that website is one that I found quite useful. I have used those values and used Photoshop to ensure my color bars match those values.

For the most part, Vegas color bars and "standard" SMPTE bars are the same, except for that one dark grey rectangle. A vectorscope will show no difference; there is just that one small bar - the one used to adjust brightness on the monitor. Place the Vegas NTSC SMPTE colorbars on the timeline and an avi or still of colorbars with the values listed on the Website - 24-24-24, and look at the Vegas waveform monitor. You will see (if you select 7.5 setup), the small bar, second from right and close to bottom, move from 18% (with Vegas) to 11% (with the other bars.) It shows exactly the same on my hardware waveform monitor.
BillyBoy wrote on 3/8/2004, 3:21 PM
The ADVID DVD commerical how-to tape is nice, has lots of things to adjust off of. There are several DVD and/or VHS titles to go into that area. The problem with putting bars or any test pattern on a web site is its not going to be very high quality. So mostly for a guide what to do, not to actually use it.

My advice, don't get overly fussy using ANY color bars. It depends what you're doing. If you are going to have something BROADCAST over TV that's different, if not, then don't sweat it. Besides, if you're going to make Aahome brew DVD, then you can go blacker than black anyways, (how's that for a oxymoron)

IF and its a big IF, you carefully calibrate your TV to your external monitor and check it every so often to be sure nothing has changed, you can get very close and never look at any bars.