Using Colormatrix

[carlmart]

Probably a dumb question on this application.

When should Colomatrix be used?

Some time ago someone told me that when converting from HD to SD with avisynth I should add this line:

ColorMatrix(Mode="Rec.709->Rec.601")

In fact, when checking on on AvsP things change a little, mostly in contrast I'd say, when I switch between using Colomatrix or not.

Should I use it or not?

[racer-x]

That would depend on what you're going to do with the footage............

If for instance you are going to edit the footage in Vegas, then you'll have to convert to RGB PC.709, because Vegas only works in RGB. If you are going to encode to dvd via TMPGEnc, then you'll need to convert to RGB REC.601 because that's what TMPGEnc will produce. If you are going to encode to H.264, then you can leave it alone.