Gamma Calibration

[glorybound]

So, I have the LG 43" LCD monitor and the Spyder Elite hardware calibration device. When everything is calibrated my brightness is about 30% and my Gamma seems off. When looking at this chart I am about 1.4 gamma. However, when I use NVIDIA Control panel and I get my Gamma to 2.2, it is a dark mess. What am I doing wrong?

http://www.lagom.nl/lcd-test/gamma_calibration.php

[narsov]

Hi,

Did you reset the monitor settings to default before calibration? You can try check CAL with the device and see the difference. What I do is, choose (2.2-6500 120 -default) and don't use suggested measure from room light if its lower white balance (depends on room light).
Mine display is at 20-25% brightness and 120 room light.
In most cases monitor's driver may cause the problem, just uninstall.

Regards,
Nikola

[glorybound]

Hi,

Did you reset the monitor settings to default before calibration? You can try check CAL with the device and see the difference. What I do is, choose (2.2-6500 120 -default) and don't use suggested measure from room light if its lower white balance (depends on room light).
Mine display is at 20-25% brightness and 120 room light.
In most cases monitor's driver may cause the problem, just uninstall.

Regards,
Nikola

What do you mean, "Check CAL with the device"? I deleted my original calibration and started over, which gave me something okay, but looking at the gamma chart I wonder. Yes, I did reset my monitor before I started. I do use the automatic room light adjustment, but my space is dark, so that should change much.

[narsov]

Check Cal is an option in Spyder software to check the gamma and white point with the setting you chose. When I measure room light I choose my settings (6500-120), not recommended from software.

[narsov]

While ago, when I was talking to Spyder support I got this answer:

Please note:
To have the correct monitor brightness is important when you edit your images.Unfortunately the room light situation will also have an impact how the monitor brightness and colours will look like (you will get a different impression if you see the monitor in a dark room or in a bright room)
The general recommendation for a photographers calibration target is Gamma 2.2, 6500 Kelvin and 120 cd/m2 These target values are right for a standard room (standard room light). In this kind of room the monitor is the brightest light source. Brighter room light conditions will cause a lower calibration quality because of the display technology and the human eye physiology.
As most people as not working in a room with standard light the recommendation is to calibrate at Gamma 2.2, 6500 Kelvin and 120 cd/m2 (Brightness Adjustment / LCD Recommendation) with activated ambient light measurement on and use the target recommendation from the ambient light measurement. This will give the best possible calibration under such circumstances.

If your room light is below the standard the recommended target display brightness value will be dropped to e.g. down to 90 cd/m2 AND the white point will be lowered also e.g. 5800 or 5000K - this is to compensate the lower room light level - please read the displayed information. This is a human eyes will percept colours different in lower light situations.

I hope it helps.

[pokoy]

Some info on monitor brightness and calibration: calibrating is always done towards a target (measured colors at certain brightness), and common industry standards are defined for print. Since paper doesn't emit light like your monitor does, a correct calibration will always dim your display as the target for print is ~40 cd/m2. Typically, everyone wants monitor colors to be vibrant so without calibration people will set their monitors to 100-120 cd/m2. However, for print this is way too bright as paper will never be able to display that brightness, resulting in images being too dark for print if your display is too bright. If you intend to produce images for print, you should set to your target brightness to a maximum of 50 cd/m2, better 30-35. These setting also work for any other display device, it's just that white color on your display will not emit way more light than white paper in daylight.
Of course,this will appear dim at first glance but will match printed colors much more than the vibrant colors when you use 100 cd/m2. After some time you'll get used to it but you should also make sure to dim any lights in your room.

As for gamma - there's no reason to touch it, whatever setting you use the calibration will counterbalance this, that's the point of calibration. If you set it too low or too high you risk less accuracy in color reproduction since your display may not be suited to go much outside of the norm, which is 2.2.

[Alex_M]

Isn't 30-50 cd/m way too dim for print? I've always read that for print 80-90 cd/m2 is going to produce best match. This seems to be correct because when I put my monitor at 90 cd/m2 brightness, I get about the same luminance as a white paper lit by diffused daylight (no direct sun).

[glorybound]

You would think. It looks better brighter, which is the way it comes, but the calibration process always makes me turn it down to around 30.

[pokoy]

Isn't 30-50 cd/m way too dim for print? I've always read that for print 80-90 cd/m2 is going to produce best match. This seems to be correct because when I put my monitor at 90 cd/m2 brightness, I get about the same luminance as a white paper lit by diffused daylight (no direct sun).

Coated paper used for print is different from what you use for your laser/inkjet printer and often proof printers will even add a slight tint to simulate print paper. From my experience, 30-40 cd/m2 will look very similar to the final product in terms of brightness. In a place I worked before, one of the high end Eizo's was set to 25 cd/m2 and it was THE proof display, it would look always exactly like the printed result, I was in awe every time I compared the result with the image on the screen. 80-90 cd/m2 are nice to look at for general work, though, and much more friendly to the eye than 150 cd/m2.

[dlparisi]

You would think. It looks better brighter, which is the way it comes, but the calibration process always makes me turn it down to around 30.

Is the calibration software having you turn the brightness down to "30" or to 30 cd/m2?

Have you tried a different calibration software, i.e., DisplayCAL (https://displaycal.net/)? I very quickly abandoned the Spyder software over displaycal - more robust IMO.

[glorybound]

Is the calibration software having you turn the brightness down to "30" or to 30 cd/m2?

Have you tried a different calibration software, i.e., DisplayCAL (https://displaycal.net/)? I very quickly abandoned the Spyder software over displaycal - more robust IMO.

The software has a target and you adjust your brightness to meet the target. In my case, 28 is the brightness that matches the target.

[dlparisi]

Yes, same here on a Dell 2415 which is at about 30 brightness for a 120 cd/m2 measured output. Just prior to the calibration and measurement is your software turning off any other display corrections (you should see it revert to a non-corrected display)? Otherwise it's measuring the corrected display and then applying the new corrections which would lead to inaccurate results.

[glorybound]

Yes, same here on a Dell 2415 which is at about 30 brightness for a 120 cd/m2 measured output. Just prior to the calibration and measurement is your software turning off any other display corrections (you should see it revert to a non-corrected display)? Otherwise it's measuring the corrected display and then applying the new corrections which would lead to inaccurate results.

I'll double check, however, I think it is looking good, so I think it is calibrating it properly.

[dlparisi]

I thought your gamma on the chart was giving you closer to 1.4 rather than 2.2.

[glorybound]

I pulled up a manual gamma chart to check if things were correct. When I squint and look at the below chart, 1 looks correct.