Graeme Gill skrev 2012-02-13 14:41:
Kristian Jörg wrote:Well, the reason I was a bit unimpressed is because this is supposed to be one of the very best TV sets to buy, and it includes full ISF controls for managing grayscale at 10% stimulus steps. Color however is only at 100% stimulus. So I can nail in the grayscale and gamma to mostly perfect result (according to the patterns used, i.e full windows cause lightness to drop a bit). Color however seems a bit more difficult. Now it is possible I have used the CP software wrongly at the 75% color intensity. It has a 75% Rec. 709 setting that I assumed should be used for the 75% W+ 75% RGB measurements. But maybe I should measure all those at 100% Rec. 709 setting since i assume the Rec 709 standard is linear? When using 75% patterns all that happens is that luminocity falls a bit, but it is all realite to white which is measured as a baseline... ?I'm afraid I have to smile a bit at all that. Rec 709 is an idealised additive display. Idealised displays have a perfect black, something no real display can achieve. So (as usual) you are faced with the issue of how do you deal with the non-perfect black, given that the transfer curve assumes that is is perfect. Non-LCD based displays are not so bad in this regard though. Then there are the viewing condition assumptions inherent in Rec 709. The channel combination targets aren't too hard to compute - add the XYZ of the individual channel target or measurement values, since Rec 709 is additive. Graeme Gill.
Just a short follow up to this little thread that I started. It was all due to a misunderstanding of what patterns to use for the 75% Rec 709 calibration settings in Chromapure. It should be 75% saturated, not 75% intensity. With correct patterns my results where correct. However if anybody tries this, there is a confirmed bug with it with at least version 2.0.10 (and probably 2.0.11) in CP, so wait for the next release before trying this.
And there is also strong indication of color decoding issues in the 2011 models of Panasonic plasmas. Something that should be fixed in the 2012 models. Bummer. There will not be a fix to the 2011 models, or even any more firmaware updates at al,l according to those who "know".