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Hi please excuse if this is a stupid question.
But I was wondering why no calibration tool seams to have a Contrast (Monitor Setting) Calibration tool? Of cause one might just set it to 50. But is that really the best way? I’m thinking 8-Bit Colors so,
if the monitor applies to much contrast and the icc LUT has to fix that won’t I loose a lot of brightness levels?
One method I used in the Past was to maximize the contrast ration (Max Brightness / Min Brightness).
Is that a Good Idea?Thanks a lot for enlightening me!
Most LCD screens have a “default” contrast value, that is the contrast value that you set before using Displaycal . Just reset your screen settings to factory default, that is usually the way you get the right value. In my experience, the “default” contrast value is usually around 75%. You can also try to set or optimize contrast (and brightness) with the help of test images such as in the ECI Monitor test kit.
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Thank you for the reply but I’m looking for a more sophisticated answer.
As mentioned I don’t want to turn Contrast to the default value (No matter weather it’s 75 or 50).
Nor do I want to refer to some eye judged test image.Most LCD screens have a “default” contrast value, that is the contrast value that you set before using Displaycal . Just reset your screen settings to factory default, that is usually the way you get the right value. In my experience, the “default” contrast value is usually around 75%. You can also try to set or optimize contrast (and brightness) with the help of test images such as in the ECI Monitor test kit.
Thank you for the reply but I’m looking for a more sophisticated answer.
As mentioned I don’t want to turn Contrast to the default value (No matter weather it’s 75 or 50).Well, but in 99% of cases, this is what you need to do (on computer LCD displays, LCD TVs are another story). Depending on how the contrast control is implemented in hardware, altering it from default will likely clip the signal (blown out highlights/crushed near black detail), or unnecessarily reduce contrast (the latter may be ok if it is desired to lower luminance further than the backlight/brightness control allows), raise the black level, or have other undesirable side effects. It’s generally only useful for analog signals (i.e. VGA).
You don’t need to touch contrast, just adjust the monitor R G B and brightness controls for the desired whitepoint and white level and let the software do the rest.
My default monitor contrast value is 50%.
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Thats exactly the Problem I’m talking about: It “might” who guarantees me that the correct value is 50 maybe it is but the default is 75? Is it really that hard to measure say 20 Brightness (Gray) points and display the Curve.
So one can manually adjust the Contrast?
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Thats exactly the Problem I’m talking about: It “might” who guarantees me that the correct value is 50 maybe it is but the default is 75? Is it really that hard to measure say 20 Brightness (Gray) points and display the Curve.
So one can manually adjust the Contrast?Even an automatically routine that starts at (0,0,0) and moves up in steps of (1,1,1) and then the same down from (255,255,255) to verify that there is no clipping. and then Samples the brightness graph with stay 40 or 100 Points .Creates a 10 point Sampling optimized for the Difference between measured and desired Curve ( e.g. Gauss Quadrature) an then goes to auto optimize Contrast via VESA/MCCS.
Should be doable.
The point is not if it’s doable or not, it’s just a lot of effort for what can be had much quicker by just looking at a near black / near white step wedge. I.e. there is nothing to be gained, neither in terms of speed nor comfort by doing this the “hard” way.
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The point is not if it’s doable or not, it’s just a lot of effort for what can be had much quicker by just looking at a near black / near white step wedge. I.e. there is nothing to be gained, neither in terms of speed nor comfort by doing this the “hard” way.
How come nothing is gained if?
Thank you for the reply but I’m looking for a more sophisticated answer.
As mentioned I don’t want to turn Contrast to the default value (No matter weather it’s 75 or 50).Well, but in 99% of cases, this is what you need to do (on computer LCD displays, LCD TVs are another story). Depending on how the contrast control is implemented in hardware, altering it from default will likely clip the signal (blown out highlights/crushed near black detail), or unnecessarily reduce contrast (the latter may be ok if it is desired to lower luminance further than the backlight/brightness control allows), raise the black level, or have other undesirable side effects. It’s generally only useful for analog signals (i.e. VGA).
Honestly Isn’t the whole point of Calibrating a Display to do it the Hard way?
You can allways just trust the Manufacturer or Eyeball it with some test image.Anyway I was thinking about implementing that but if tis is not Interesting I’ll just keep it to my self.
Honestly Isn’t the whole point of Calibrating a Display to do it the Hard way?
No, that’s the easy way. If you have ever adjusted the grayscale using 10-pt controls on a TV (a possibility that doesn’t even exist on most computer monitors), you probably know that it involves a lot of fiddling with knobs, while calibration using the videoLUT is fully automatic.
By the way, if the only point is to avoid clipping, calibration already takes care of that. You only need to use test images if you want to know the “ideal” contrast value that doesn’t sacrifice any brightness, and in 99 out of 100 times you’ll arrive at the (factory) default value.
