How to get better contrast out of Intel GPU's?
by ordealbyfire83 from LinuxQuestions.org on (#6E66M)
Is it at all possible to increase the contrast on a laptop with integrated Intel graphics (probably GM45). I have a Lenovo Thinkpad T500 and have done some measurements with a colorimeter. The physical LCD panel is an LG-Phillips, but I forget the actual model number. I'd have to take the case apart again to see the label. The colorimeter reports a contrast around 50:1. But if I take out the panel and put it in a Dell laptop with an nvidia GPU, the colorimeter shows 245:1.
It seems laptop manufacturers simply pass off the LCD manufacturer's theoretical specs when providing contrast measurements instead of saying what kind of results will be achieved in that laptop.
I've done several measurements at different brightness levels. The contrast is measured the same, but the eye perceives the contrast to be better at higher brigheness. But it is not. The problem is that the black point is simply too bright. As such it is really not feasible to look at digital photographs, and I have to plug in an external display for this purpose.
It seems that the GPU uses pulse width modulation. Does anyone know any hack for contrast using intel_reg?
At first I thought it was just my laptop. But I have now checked three T500's and a Thinkpad Edge. They all do the same, although the Edge is even worse. It shows a contrast of 44:1 with a white point of 7300K. Seriously, no photograph could ever look good on that.
It seems laptop manufacturers simply pass off the LCD manufacturer's theoretical specs when providing contrast measurements instead of saying what kind of results will be achieved in that laptop.
I've done several measurements at different brightness levels. The contrast is measured the same, but the eye perceives the contrast to be better at higher brigheness. But it is not. The problem is that the black point is simply too bright. As such it is really not feasible to look at digital photographs, and I have to plug in an external display for this purpose.
It seems that the GPU uses pulse width modulation. Does anyone know any hack for contrast using intel_reg?
At first I thought it was just my laptop. But I have now checked three T500's and a Thinkpad Edge. They all do the same, although the Edge is even worse. It shows a contrast of 44:1 with a white point of 7300K. Seriously, no photograph could ever look good on that.