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Colour Bars
I have been comparing the colour bars generated by my Pal VX2100E with the media generators in Vegas Movie studio. I get an exact match with the NTSC bars, but the Pal bar in Vegas shows a pure white as compared with the light grey in Vegas NTSC and my camcorder. Why is this and what am I supposed to do with the colour bars anyway
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7 Replies
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I have no idea why you’re seeing a brightness difference between the two.
Maybe there are slightly different standards?You use colour bars to calibrate a video monitor, preferably one that has a “blue gun only” switch.
Here’s an article on how to do this properly.
BTW, thanks for spelling colour properly 🙂Mike
a Canadian -
Thanks Mike.
I always spell colour this way. It keeps me in good humour!
Alex
an Englishman -
I guess that’s why we’re such good neighbours 🙂
p.s. Glad the link was of some help. -
Yes! So true. Pal PD150’s show the same bar levels. For the life of me I don’t know why Sony make their small cameras without PAL EBU (European Broadcast Union) bars. PAL EBU bars are 75% 100/0/75/0 bars with the white level set at 1 volt.
What you are seeing on your PAL camera are North American SMPTE NTSC bars which have the white level set at 75%. If you put both sets of Vegas bars on a time line plus some bar footage from your VX2100 and open your Waveform and Vector scope in Vegas you can see the levels change from 75% white on the SMPTE NTSC bars to 100% white on the SMPTE PAL bars. Pretty sure you will find the white level on your VX bars are 75%. Go figure.
The important to remember is that for correct broadcast levels in the UK your video levels, peak to peak, should be 1 volt. 0 volts for black level and 1 volt for your peak white levels. Beware of your black levels in Vegas as they are not ‘video black’ as Vegas works in computer 8 bit RGB levels. These go from 0 black to 255 white. Whereas the correct video gamut goes from 16 for black to 235 for white. Try putting some media generator black and white on the timeline and watch their levels in the waveform monitor. Now try applying the ‘broadcast colours’ plug-in. Uncheck the 7.5 IRE setup box, only used in NTSC Nth America, and make sure the ‘studio RGB’ box is ticked and select ‘conservative’ from the drop down menu. The levels you will now see as you drag through the black and white media on your timeline are black at 0 and white at 100. These are your correct delivery levels for ALL your PAL video content if aimed for broadcast. Not critical for non-broadcast delivery but a good practice to get into as nobody can then accuse you of delivering non-standard levels.
You can find some useful info on colour bars (downloadable) in the 8 bit editing world at:
https://www.belle-nuit.com/testchart.html
Chris Young
CYV Productions
Sydney -
Thanks Chris. I’m glad it’s not just my camcorder, nor my eyes for that matter. I’ll study your notes and perhaps have a try.
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Hi Chris
Presumably you are also running your Vegas ‘scopes on the Studio RGB setting. After a lifetime on Discreet Edit, it seems weird to have to jump through so many hoops just to get normal levels.
Regards
Kim Nance
Armadillo Post -
Kim ~
Yes, scopes set to Studio RGB. I know what you mean as we still have Edit v6.0 running with Targa SDX studio, Abekas 3D and Madras. Great system but sadly it got left behind. I shudder when I think how much we paid for that system. Oh well, time marches on but I must say with two systems running full time with Vegas and one part time they have proved to be very reliable and can cover ninety percent of what we need for corporate and broadcast delivery. Can’t complain then can I?
Chris Young
CYV Productions
Sydney
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