PC Cap/Edit/Render --> Gamma Adjustment for Mac Viewers? at DVinfo.net

Bill Binder · August 3rd, 2005, 11:21 AM

I capture, edit, render, and encode on a PC using my GS400, Vegas, and Sorenson Squeeze. I typically encode to BOTH Windows Media and Quicktime formats for publishing on the Web (between those two formats, nearly anyone can watch my vids without installing anything). My question relates to gamma correction for Mac viewers. I pretty much assume the Quicktime versions are getting watched by Mac owners, not PC owners (while that may not be entirely true, it's true enough). Anyway, I think I've read that I need to crank down my gamma for Mac viewers (make it darken gamma-wise) otherwise the picture will be too washed out for them. Do I have that correct? Or do I need to make it lighter? Also, how do I know how much to adjust gamma? In Sorenson, it is super-easy for me to apply a gamma filter during the encode, but I adjust by "points," and have no idea how much to adjust by. I've been setting it to -10 and hoping that works. Any tips are much appreciated...

Dan Euritt · August 3rd, 2005, 04:49 PM

Quote:

Originally Posted by Bill Binder

I pretty much assume the Quicktime versions are getting watched by Mac owners, not PC owners (while that may not be entirely true, it's true enough)

that assumption is totally incorrect, because only about 3% of the computers on the internet are macs... even apple has stated in the past that ~97% of the quicktime downloads they see are from pc's.

so unless your video is specifically targeted to mac users, don't worry about mac gamma... the gamma differences between lcd and crt monitors are a far bigger issue.

lcd's are so bright that i don't lighten my web video anymore, because it just gets blown out when viewed on an lcd monitor.

Bill Binder · August 4th, 2005, 10:34 AM

So classic, I knew someone was going to jump on that Mac/QT comment of mine. Well, that is good to know and thanks for sharing, I'm better informed now especially about the CRT vs. LCD thing -- very helpful to know.

But, I will say this, my videos are only really distributed on the web for friends and family via a video blog, and among that close-knit group, the people using the QT versions are entirely mac addicts. So in my specific application, I think my assumption works out fine. Also, if any of those other PC people downloading QT are like me, I've got to say if I had a choice between two links to the same video -- WMV and MOV -- I'd click on the WMV version for several reasons. So under the conditions where I'm providing both versions to surfers, I'm tempted to say my assumption holds water to some extent a little more that if I ONLY posted a MOV version. But maybe I'm just a little ignorant on that subject -- times change I guess.

It does, however, seems think the CRT vs. LCD argument is a really good one, and one that'll probably cause me not to worry about it anymore. BUT, I'm STILL interesting in knowing how this works between PCs and Macs. If I did want to make an adjustment, do I increase or decrease gamme when going FROM a PC to a Mac?

Christopher Lefchik · August 4th, 2005, 11:03 AM

As a PC user with a CRT who uses QuickTime to watch movie trailers, I find that the QuickTime videos are already dark enough. I don't know if the trailers on the Apple site have had their gamma darkened (I doubt it, as they have many visitors running Windows), but I definitely would not want them any darker.

Your situation is different, in which case decreasing the gamma would probably be okay. As to how much I unfortunately can't help you.

Dan is right about LCDs. I also have an LCD, which on the default brightness setting (50%) is actually too bright, resulting in muddy blacks on videos.

August 3rd, 2005, 11:21 AM	#1
Bill Binder Major Player Join Date: Jun 2005 Location: San Francisco Posts: 542	PC Cap/Edit/Render --> Gamma Adjustment for Mac Viewers? I capture, edit, render, and encode on a PC using my GS400, Vegas, and Sorenson Squeeze. I typically encode to BOTH Windows Media and Quicktime formats for publishing on the Web (between those two formats, nearly anyone can watch my vids without installing anything). My question relates to gamma correction for Mac viewers. I pretty much assume the Quicktime versions are getting watched by Mac owners, not PC owners (while that may not be entirely true, it's true enough). Anyway, I think I've read that I need to crank down my gamma for Mac viewers (make it darken gamma-wise) otherwise the picture will be too washed out for them. Do I have that correct? Or do I need to make it lighter? Also, how do I know how much to adjust gamma? In Sorenson, it is super-easy for me to apply a gamma filter during the encode, but I adjust by "points," and have no idea how much to adjust by. I've been setting it to -10 and hoping that works. Any tips are much appreciated...

August 4th, 2005, 10:34 AM	#3
Bill Binder Major Player Join Date: Jun 2005 Location: San Francisco Posts: 542	So classic, I knew someone was going to jump on that Mac/QT comment of mine. Well, that is good to know and thanks for sharing, I'm better informed now especially about the CRT vs. LCD thing -- very helpful to know. But, I will say this, my videos are only really distributed on the web for friends and family via a video blog, and among that close-knit group, the people using the QT versions are entirely mac addicts. So in my specific application, I think my assumption works out fine. Also, if any of those other PC people downloading QT are like me, I've got to say if I had a choice between two links to the same video -- WMV and MOV -- I'd click on the WMV version for several reasons. So under the conditions where I'm providing both versions to surfers, I'm tempted to say my assumption holds water to some extent a little more that if I ONLY posted a MOV version. But maybe I'm just a little ignorant on that subject -- times change I guess. It does, however, seems think the CRT vs. LCD argument is a really good one, and one that'll probably cause me not to worry about it anymore. BUT, I'm STILL interesting in knowing how this works between PCs and Macs. If I did want to make an adjustment, do I increase or decrease gamme when going FROM a PC to a Mac?

August 4th, 2005, 11:03 AM	#4
Christopher Lefchik Trustee Join Date: Jul 2003 Location: US Posts: 1,152	As a PC user with a CRT who uses QuickTime to watch movie trailers, I find that the QuickTime videos are already dark enough. I don't know if the trailers on the Apple site have had their gamma darkened (I doubt it, as they have many visitors running Windows), but I definitely would not want them any darker. Your situation is different, in which case decreasing the gamma would probably be okay. As to how much I unfortunately can't help you. Dan is right about LCDs. I also have an LCD, which on the default brightness setting (50%) is actually too bright, resulting in muddy blacks on videos.