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Recently have gotten the use of an i1 Match colorimeter. The software, EyeOne MatchPro 3.6.2 is easy to use and does all the measurements and then generates a cold profile. great. But what should i set my monitor brightness and contrast to prior to starting the calibration?

There is no way my Benq2420TE should be left at 100% brightness and 50% contrast.(the defaults) Those are retina burning settings and only look good when the light is dimmed as a result of enabling stereoscopic vision.

Any suggestions?
On most monitors, the contrast should usually be set to the default. Sometimes it can help to reduce the contrast a little bit if the default causes white to have a different hue than grays.

The brightness usually doesn't matter because it just controls the backlight, so you can change it after calibrating without affecting the gamma or white point calibration. Just pick something comfortable.
Tnx. In addition to improving the color and image quality, I am also trying to understand 'lagginess'. After all, this is the reason these monitors exist-to decrease lag. In trying to understand these fast monitors I have come across the concept of 'overdrive'. This article :
http://www.bit-tech.net/hardware/monitor...overdrive/
explains it well along with the side effects.
They say:
" the precise details of how overdrive technology causes input lag aren’t clear"
The monitor I am using has a switchable overdrive setting called 'AMA' which can be off, High or premium.
I can see the difference caused by this setting by visiting this web page:
http://www.testufo.com/#test=inversion
and switching the overdrive off to high.
The multicolored panel is more pronounced when overdrive is off but tends towards the expected gray as the overdrive is turned up. This means the LCD crystals are switching faster and the motion of the 'gray square' across the screen is not fast enough to catch the crystal switching 'in the act'. Yes?
Interestingly, the left side of my panel depicts more color than the right side as the square moves across the screen. Why?
But if overdrive causes the crystals to switch faster, why is there MORE lag? I would expect less.
This review of thie 2420T:
http://www.prad.de/en/monitore/review/20...part7.html
also discusses overdrive. I do not understand this:
"When overdrive is active, the 120Hz times are identical to those at 60Hz. Without overdrive, the values are reduced by about 60 percent due to the faster image sequence. The effects on the frame (which only lasts about half as long) are identical."

When you turn off overdrive, crystal switching is slower. So the 120 hz times should be more different from the 60 hz times than when overdrive is off. But they are saying the opposite. Clearly I am missing something fundamental here.

I understand why overdrive can cause ghosting. - it pushes the crystal beyond the angle it should be by a little bit - 'overshoot' and so a transition from black to dark blue may momentarily go to light blue. But why would there be lag?
The first overdrive article is old. PVA monitors at the time were notorious for lag. The Dell 2405FPW had a two-frame lag, and the Samsung 244T had a three-frame lag. Some speculated this was caused by the overdrive implementation because older PVA monitors without overdrive didn't have that kind of lag. The reasoning was the overdrive needed to buffer and process frames to overcome the slow response times of PVA panels. Newer PVA monitors without lag like the Samsung 2333T seemed to support that theory because the response times were terrible even with overdrive active.

Lag and response times are separate things. Overdrive doesn't have to add lag. That only seemed to be a problem with PVA monitors. Many TN and IPS monitors with overdrive have no significant lag. On monitors where overdrive is an option, I've never seen overdrive add lag.
tnx for clearing that up.
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