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Discussion Starter · #1 ·
I have a about 2200 hrs on my Pro-111FD plasma TV. Recently, I've been trying my hand at calibration (Chroma 5/CalMAN) and I noticed that in the ISF-Day (and ISF-Auto) mode the level of blue is lower along the entire grayscale.


In order to correct the grayscale on ISF-Day I had to bump up the B-High (Gain) to 5 or 6 when it used to be around 3. Seems a little excessive to me. (I also had to increase the B-Low from 0 to 1.)


Is this kind of change something that's typical of plasma TVs as they age and the reason they need to be recalibrated periodically? If not, I'll have to figure out what might be happening with the C5 (although the blue channel drop-out was supposed to be corrected in the current version of the software).

 

ISF-DayReCalibration082009.pdf 255.232421875k . file

 

ISF-DayCalibrationCheck082009.pdf 264.1728515625k . file

 

ISF-AutoCalibrationCheck082109.pdf 199.55078125k . file
 

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Discussion Starter · #3 ·

Quote:
Originally Posted by SierraMikeBravo /forum/post/17041863


It all depends on the age of the panel when you calibrated it initially, and what meter was used to calibrate it. Yes, as the panel ages there is often a shift in the grayscale which does affect the color perception.

The panel was new and I had it calibrated after I put about 175 hours of break-in time on it (with D-Nice's settings). I had it calibrated professionally after that and my calibrator used a Minolta CS200 (much better than my C5, and more consistent, I'm sure!).


Well, at least that addresses the possibility that there may have been a shift in the grayscale and all of it is not attributable to me being so 'green' (no pun intended) at calibrating! As you can see from my ISF-Day calibration report, the grayscale still isn't great by any stretch of the imagination, but if I keep futzing with it, I might get it looking good yet!


So, when something like that happens and the settings that worked before no longer do the job, is it best to start with those settings as a baseline and begin adjusting from there, or is it better to go back to neutral (zero?) settings and start again from scratch?


Thanks for the info, SMB!
 

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There are no "neutral" settings. There is only what there is. The values are essentially arbitrary...but both cuts and gains are usually interactive. You are trying to achieve a balance between the three colors despite what values they may have. The numbers are essentialy there for reference. If you are getting close to maxing out anyone one of the color controls, then I would back off on all three and begin again, but you should still have plenty of dynamic range left on your panel.
 

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Quote:
Originally Posted by gerianne /forum/post/17041237


I have a about 2200 hrs on my Pro-111FD plasma TV. Recently, I've been trying my hand at calibration (Chroma 5/CalMAN) and I noticed that in the ISF-Day (and ISF-Auto) mode the level of blue is lower along the entire grayscale.


In order to correct the grayscale on ISF-Day I had to bump up the B-High (Gain) to 5 or 6 when it used to be around 3. Seems a little excessive to me. (I also had to increase the B-Low from 0 to 1.)


Is this kind of change something that's typical of plasma TVs as they age and the reason they need to be recalibrated periodically? If not, I'll have to figure out what might be happening with the C5 (although the blue channel drop-out was supposed to be corrected in the current version of the software).

Yes your display can change by that much during 2000 of use (one of my 111FDs also shifted by this much). You can fix your grayscale between 30 and 50% stimuli by using the CMS controls. You dip in gamma at 90% can be corrected using the 9 point gamma controls.
 

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Discussion Starter · #6 ·

Quote:
Originally Posted by D-Nice /forum/post/17044382


Yes your display can change by that much during 2000 of use (one of my 111FDs also shifted by this much). You can fix your grayscale between 30 and 50% stimuli by using the CMS controls. You dip in gamma at 90% can be corrected using the 9 point gamma controls.

Thank you both (D-Nice and SMB) again for confirming this.


Great advice on how to correct this, D-Nice! Thank you. I'll definitely give this a try.


Should I use the 9 point gamma controls sparingly, i.e., decrease/increase by one or two and if that doesn't correct the problem should I go back to where it was before?
 
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