Colr Bars

Vegascat40 wrote on 9/1/2008, 9:42 AM

Your input is appreciated:

I was tweeking an LCD Hi-def 720p monitor using SMPTE color bars
generated in Vegas. I noticed that there is an extreme difference in the default picture and settings at the composite input versus the component input to the monitor. At the component input I can see all 3 IRE bars, and at the composite input no matter where the brightness control is I can only see the 11.5 IRE
bar? I thought SMPTE bars were designed to accomodate a composite
signal, but the adjustments I made using the bars generated through
the component input are far more accurate. I don't understand why there
is such a difference? I wonder if I should be using a Hi-def test
pattern as well? Does anybody have any thoughts on this subject?

Rgds/Steve...

Comments

GlennChan wrote on 9/1/2008, 9:45 AM

1- What's your preview device?

2- It could potentially be that DV cameras (almost all of them) will incorrectly put analog black level too low. So that could explain why you only see the rightmost PLUGE bar.

Vegascat40 wrote on 9/1/2008, 1:02 PM

Hmmmmmmmmmm thanks for that I think that might be it! I actually had the problem when I was generating bars off my Canon XH-A1.

By analog I assume you mean composite video?

Rgds/Steve.

GlennChan wrote on 9/1/2008, 6:59 PM

I suppose in this case it would be in reference to composite video.