Originally Posted by gremmy
Without instrumentation, how would you recommend that a person "calibrate" for gamma2? It this simply a matter of messing with the RGB gain/bias controls until it approximates the picture provided with gamma turned off? Is this even possible?
Thanks for your thoughts.
I'm sorry Gremmy, I only commented because of the title of this thread. The title suggests we are talking about "calibration" which presumes folks are making adjustments with the equipment required to measure the exact changes taking place.
Your use of the word "messing" is appropriate, because that is eactly what is being done when the proper equipment is not being used when making adjustments.
I have no suggestions on how to tweak grayscale and gamma response without the proper equipment. I certainly did my share of messing with RGB gain/bias controls long before I owned my current calibration gear, but I also know these efforts would never lead to a proper calibration except by accident.
If I may, I would echo the warning offered by our friend "wm"... folks without the knowledge & equipment should be very careful when messing in the service/factory menu.
SOWK is advising folks to make an adjustment to a panel driver, which is an area a calibrator would not adjust during a calibration. The panel driver change was and continues to be bad advice.
I am guilty of sharing info on my post calibration settings for the 51 and 51A. I will agree in hindsight with "wm" this practice is right on the edge of dangerous in the hands of an owner who could make a serious mess of their projector settings.
May I humbly suggest service menu
tweaks only be posted by those who have the proper equipment to verify the results of their adjustments.
I would go further and humbly suggest projector owners following this or any other "calibration/tweaking" thread only consider trying the service menu changes offered by folks with the proper equipment. Eventhen , you are doing so with the understanding of the associated risk.
I hope everyone takes these comments in the spirit intended.
The interaction of the RGB bias/gain and Gamma choices are very complex, and the slightest change in one area, can have dramatic effects in another. Often the calibration process requires a exhaustive range of tweaks from top to bottom of the luminance range, until a compromise set of adjustments serve to offer the best balance of performance across the grayscale/gamma curve. Making adjustments strictly on the low end of the curve may produce wonderful results in the lowend performance, only to have the middle and high end drift far from ideal performance.
"wm" also brings up an excellent point regarding additional gamma curve options, and I would expect he is able to offer just such an alternative for projectors he calibrates. Even though I have calibration gear, I look forward to sending "wm" one of my projectors someday, so he can work his magic in areas I would never dream of addressing.
I'm just don't yet own a projector on his list.