gamma shift?

Patryk Rebisz wrote on 5/22/2005, 2:23 AM

when i preview the project through the Previwe function (going through FireWire into my computer then into the TV) the project has the proper black levels but when i burn a DVD the blacks a washed out?

Comments

farss wrote on 5/22/2005, 3:41 AM

It's the DVD player. If you check the encoded mpeg file it matches the levels in the source file. Check the composite output of the player and you'll see the levels have been compressed to between 16 and 235. I suspect the component outputs of DVD players don't do this.
Bob.

Patryk Rebisz wrote on 5/23/2005, 2:14 AM

is there a way around it?

BillyBoy wrote on 5/23/2005, 8:40 PM

Welcome to the real world. If you are only doing work for yourself and you know your project will be played on a particular DVD player and it changes the luminance by X, you can over adjust in the opposite direction to compensate so when its played back the levels are closer to what they should be. This of course isn't that good an idea if you are doing work for others because somebody else's DVD player may be "off" in the opposite direction making your adjustment compound.

As I've mentioned in the video forum I once found a very lengthy article that went on pages and pages (forget to bookmark) that reported the lab test results for lots of popular DVD players. Almost all of them, regardless of price, even models costing thousands of dollars had overly bright levels with a few having the IDE for whites at 105 or higher. It should be 100. Most weren't off that much, 98-103 was typical, but it just goes to show even the manufacturers don't meet specs exactly which is why I opened with saying welcome to the real world. Lots of noise is made on this topic and it does boil down to noise because you never know what DVD player you DVD will be played back on and we didn't even get into the end user having a badly calibrated tv which always compounds the problem.