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Is it better to set contrast and brightness to get the best result on the hi/lo pattern and pluge pattern or set them to produce the best gamma?
 

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Greetings


You want both and you should be able to get both ... depending on the TV. If you can't have good gamma ... then you aim for optimal brightness and contrast settings.


Regards
 

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Michael, first of all many thanks for your answers.



So, supposing you have a colorimeter, your advice would be:
  1. First setting Brightness/Contrast with the master controls and SD patterns (GetGray for instance), then select the gamma closest to 2.2 (if you have control about) and finally retweak the master Brightness/Contrast in order to acquire a more accurate gamma (that is, without dvd patterns just moving the master controls to "move" the gamma curve up and down)


    or

  2. Leave Brigthness/Contrast at 50%, choose gamma and then setting Brightness/Contrast with the usual patterns (like the GetGray SD patterns).




I'm really very confused but what would you expect from a newbie?
 

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Greetings


okay ...


Set brightness and contrast right ... then put up one of those split ramp gray patterns like what GG has ... and change the Gamma setting on the TV ... until you find the setting that is the darkest ... and start there.


That's usually the closest given the way TV settings are these days. Then recheck the brightness and contrast.


I have noted of late that some TVs give a better gamma curve when the contrast is cranked ... which is a bad idea. Somehow the TV just behaves like that. Well if you crank contrast to get the best gamma ... you lose both detail and you introduce color shifting. Hardly a best fit for the gamma. Good gamma ... bad picture ...


Regards
 

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Just thought I would share a recent experience.


Trying to adjust and decide on which settings to use as far as contrast and brightness go using both a calibration disk by eye and Calman 3 software.


Going by eye I was basically setting the brightness and contrast to avoid exceeding the limitations of the display. Then when I checked it using the same calibration disk using a colorometer and Calman 3 software I had a hitch in the high end of the gamma point scale that could only be corrected by lowering the displays contrast down quite a bit. Naturally with the lowered contrast the picture started to seem a little under saturated on the colors.


After much research and with feed back from Bill and Derek at Calman. I seemed to find the magic combination. A big thumbs up to the Calman team for putting together the software they did and including all the detailed help info.

It seems that the Sony ES DVD player which went through a receiver that upconverted to 1080P had a different gamma dynamic than the display.


Dropping the contrast 2 clicks on the receiver allowed me to open the contrast back up on the display and maintain a flat gamma point measure from start to finish. The color saturation after calibration was perfect. Everything just came together.


Which brings up an interesting point. Probably the ideal way to do a calibration is to use a stand alone pattern generator and calibrate the specific input. Then connect the device and run the calibration disk. If the measurments of the device are off then try and bring it back into alignment using any adjustments on the device only. Unfortunatly most devices do not have the adjustments we would need. If the device being off is really a bother than we would have to add a video processor to bring it back into spec.


Sad to say some devices probably don't adhere as tight to a standard as we might hope.


Maybe as more and more videophiles get involved in calibration of their display's. The manufactures will take a little more time getting their product closer to 0 tolerance.
 

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Very interesting data...



I think is time for tweaking my Denon 2930 settings (Chroma level, brightness, contrast, etc.) before come to a conclusion with my DLP front projector.


Sincerely, Michael and eddiscus, keep up the good work.
 

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How accurate is the Gamma Check screen in Avia test disk? I set my Panny Pro plasma gamma to 2.2 .When I check with the Avia test pattern I find its closer to 1.8 , I may have to adjust the gamma setting on the Panny to 2.5 to get a higher gamma reading on the Avia test disk .
 
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