CurtPalme.com Home Theater Forum

garyfritz · Joined: 08 Apr 2006 Posts: 12026 Location: Fort Collins, CO

I've got a new PS3, and while I haven't had time to play with it much yet, I did download a few trailers. One of them, Ironman, I'd seen at the theater, and it was clear the image I was getting was significantly darker than it should have been. Looks like a gamma problem. I was happy with the picture I'd been getting with my SD player (Momitsu v880N) but the PS3 looks dark. Both of them were running through a Moome EXT-HD box.

I decided to run a grayscale using the GetGray SD disk, using both the Momitsu and the PS3. That will tell me how the PS3's SD playback compares. The BluRay playback might be different, but you would hope it would be consistent between SD and BD.

See attached pix. I've set up the Momitsu readings as the "reference," so they're dotted. The Luminance graph is a bit busy but it's clear the PS3 is darker, especially at low IREs. The Gamma graph shows significantly higher gamma (== darker display) for all colors, except high-IRE blues. The color temps are different but fairly similar. Note that the PS3 doesn't show a temp for 10%, apparently because it's too dark to read there.

Finally, I've included the Momitsu & PS3 measurements. You can see the PS3's Y measurement (in cd/m^2, since I haven't figured out how to get Y to display in ftL) is much lower at low IREs -- in fact the 0% reading didn't register at all -- while the 100% reading is only about 10% low on the PS3.

What does this tell me? Well clearly the two players are *different*. I guess the brightness/whatever settings on the two players may be causing part of this. That may not be a big problem if I replace the Momitsu with the PS3, but if I can't match the PS3's gamma characteristics with other sources (Momitsu, HD satellite, whatever), I may have a problem. Projector grayscale settings are usually universal, so you can't have different settings for different sources.

Is there any point in setting the grayscale to the PS3 using an SD test disk? I've got the AVCHD RC1 ISO, which I'm supposed to be able to burn to a normal DVD and play in a Blu-Ray player, but I haven't burned it yet. I suspect I should set the grayscale using a BluRay source in the PS3, but that's going to suck if it means the SD grayscale is way off. For now there are a lot more watching options on SD than on BD. I can't even set up the PS3 for BD and use the Momitsu for SD playback, if the two players are so different.

I haven't yet found the brightness/etc settings on the PS3. I assume there are some? Should I leave them alone, in the interest of sending the most-unmolested signal out the HDMI port, and try to do all my adjustments in the projector? Or should I use the PS3's Brightness control to tweak any gamma issues the projector & Moome can't fix?

Thanks for any suggestions...
Gary

garyfritz · Joined: 08 Apr 2006 Posts: 12026 Location: Fort Collins, CO

The PS3 has a setting for "RGB Full Range (HDMI)" which chooses between Limited (16-235 levels) and Full (0-255 levels). Which should we use for a Moome HDMI box? I had it on Limited for the above measurements.

*IS* there a Brightness setting in the PS3? I can't find it anywhere...

garyfritz · Joined: 08 Apr 2006 Posts: 12026 Location: Fort Collins, CO

Just talkin' to myself here I guess......... Smile

According to http://www.avsforum.com/avs-vb/showpost.php?p=13722561&postcount=658:

ecrabb · Posted: Wed Jun 18, 2008 8:01 pm Post subject:

Gary,

I don't have time to go into detail right now, nor read the other thread, but... Any film-based source material on BD is encoded as 1080p@24, NOT as 1080i. So, if you're watching mostly film-source material as most of us are, this won't be an issue.

As for the 1080i deinterlace issue, if the source is truly 1080i (i.e. SHOT at 1080i - football, or Jay Leno or something), and you display at 1080p, then yes, you'll be scaling the fields to frames. But, that's ANY time you display non-telecined interlaced content as non-interlaced. That's where high-end processors with motion-adaptive de-interlacing algorithms come in, and that would be where the PS3 (and probably practically any other player), unless it has high-end motion adaptive de-interlacing built-in.

As for your issue, that's just weird. Unless the Momitsu has gamma control or is decoding something incorrectly, or the PS3 is doing the same, I can't see why color balance would be different. Gamma, maybe - but, color balance surprises me.

SC

garyfritz · Joined: 08 Apr 2006 Posts: 12026 Location: Fort Collins, CO

OK, that's what I thought. The AVS HD 709 disk is an exception because its test patterns are encoded in 1080i (I think). I'm a little surprised the PS3 apparently displays it in 1080i (since I saw twitter) when you've told it your display only handles 720p. (And 480p, which apparently can't be disabled.)

ecrabb · Posted: Wed Jun 18, 2008 10:07 pm Post subject:

Huh? If you've deselected 1080i and 1080p in the display prefs, then the PS3 wouldn't be displaying anything in 1080i.

Even watching the AVS disk in 720p, you might have seen twitter anyway, because the twitter is in the source. How it looks and whether it exhibits field twitter would depend on how the PS3 de-interlaces and scales the 540 fields to the 720p frames, and also on what sort of vertical filtering the scaling algorithm uses.

Not being able to disable 480p is one thing that really annoys me about the PS3... a lot of BD's have supplemental material that the PS3 switches to 480p on (stupid behavior, IMHO). You should be able to say, "Scale ALL content to the highest resolution I have selected." I should also be able to deselect 480p - I don't EVER want to see 480p output to my display. It looks like ass.

SC

garyfritz · Joined: 08 Apr 2006 Posts: 12026 Location: Fort Collins, CO

Hm. I suppose the twitter could be visible with 720p, but it seems unlikely...

Yeah. Whyinhell do they force you to accept 480p!? That's one complaint I have about the PS3 -- it switches resolution all the time. I find it annoying when my projector flickers and displays "No sync" when the PS3 is switching from one activity to another. Let me set the output format, dammit, and scale to it! ALL the time!!