CurtPalme.com Home Theater Forum

Elix · Joined: 23 Jan 2011 Posts: 5

Do you know any heavy-duty meters which are suited for plasma calibration? I might wanna rent one.

**kal** · Posted: Sun Jan 23, 2011 7:06 pm Post subject:

Elix · Joined: 23 Jan 2011 Posts: 5

Thanks! That article cleared things up. As I understand, I should grab a spectroradiometer somewhere (Eye Pro, for example) and build a calibration file for my i1 Diplay 2 in ColorHCFR using simultaneous measures? Will that work?

**kal** · Posted: Mon Jan 24, 2011 1:31 am Post subject:

Neologist · Joined: 14 Jun 2010 Posts: 6

Hey guys,

it´s me again.

So I finally managed to purchase a new probe.
I remeasured my G20 and calibrated it.
Funny thing is, result´s are pretty much the same. Color tints within a range of grey grades. No matter if callibrated settings oder pre-installed ones like THX.

Probably it actually is the a tv´s color production.

Anyway, my gamma is a bit low and it drops at higher IREs. Where should I preferrably have the gamme curve to match reference? in the lower IREs or the higher ones?
Besides: What can I do to rise or straighten the gamma anyway? What setting do actually affect gamma?

Best regards,

Neologist

Elix · Joined: 23 Jan 2011 Posts: 5

This is frustrating. Reviews never mentioned anything like this. I suspect it's just that plasma doesn't handle gradients too well. Anyway I still want to get a photo radiometer and try calibrating my GT20 once again.

Neologist · Joined: 14 Jun 2010 Posts: 6

Hey dudes,

I managed to recalibrate the TV set on my LG BD370 and the PS3. Took me all freakin´night but I think it´s worth the expense.

The grey-scale deviance is less now and I managed to move the deviance down to the lower IREs. I resulted in a more straight and higher gamma of 2.14 now. I checked it by watching Star Wars in a darkened room and was quite wowed by the picture.
Great shadow detail and still glowy and genuine colors. I mean, the picture was awesome on THX already and the pre-callibrated values were quite good. Still I think I squeezed some additional contrast and more balanced picture out of it.
I attached the results below.

Regarding the grey-scale-tints:

What I found is that the GW20 has a tendency to push the red in the 30 IRE. By also using IRE 25, 35 and 70 it´s possible to balance out this sudden rise and have this tendency to spread among the other IREs. I thought this might be quiet useful since the human eye adapts quite fast and would sense a difference between 2 shades of grey (especially with a red tint) more sesitively than a slight tint overall.
Also I do think that this drift to red might be due to a plasma´s operation to produce colors. Plasmas use additive color while LCDs use substractive color mixing. The plasma will try to achieve a certain shade of grey by intermittently firing up plasma cells with blue, green and red in the same amount. An effect that you might see when shades of color or tones are supposed to go from light to dark (like a picture of a sky) is banding. If you have this ladder-patterns you will encounter banding as well. Since your eye is quite sensitive to red what you see is the red tinted band.

Best regards,

Neologist