Color calibration at maximum brightness

[SpyderDoom]

Hello and a happy new year!

I just got a Spyder4Pro. I read that colorimeters are less accurate at low brightness levels. Would it make sense to calibrate my monitor at full brightness and then turn down the backlight to the desired level? My thinking is that it will result in more accurate gamma curve. Does the gamma of a panel really depend on the backlight?

Thanks in advance!

 

[Ron AKA]

No. If you want the most accurate colour you will set your brightness to about 120 cd/m2, or depending on your calibrator, it will do it for you.

Try and find your monitor or something similar in this list of reviews. Have a look at how they calibrate the monitor for maximum accuracy.

 

[VirtualMirage]

Hello and a happy new year!
I just got a Spyder4Pro. I read that colorimeters are less accurate at low brightness levels. Would it make sense to calibrate my monitor at full brightness and then turn down the backlight to the desired level? My thinking is that it will result in more accurate gamma curve. Does the gamma of a panel really depend on the backlight?
Thanks in advance!

I would not recommend this.

You will experience color shift and a shift in your gamma curve. The backlight plays a very important part in what/how those colors and your gamma curve are displayed. Those colors that are displayed do not remain constant as the brightness is changed, especially when going from its brightest setting down to a much lower setting.

You are better off calibrating at the brightness level you intend to be working in.

 

[SpyderDoom]

No. If you want the most accurate colour you will set your brightness to about 120 cd/m2, or depending on your calibrator, it will do it for you.

Try and find your monitor or something similar in this list of reviews. Have a look at how they calibrate the monitor for maximum accuracy.

Thank you very much for the list. My monitor isn't listed, but I can see similar ones.

 

[SpyderDoom]

Hello and a happy new year!
I just got a Spyder4Pro. I read that colorimeters are less accurate at low brightness levels. Would it make sense to calibrate my monitor at full brightness and then turn down the backlight to the desired level? My thinking is that it will result in more accurate gamma curve. Does the gamma of a panel really depend on the backlight?
Thanks in advance!

I would not recommend this.

You will experience color shift and a shift in your gamma curve. The backlight plays a very important part in what/how those colors and your gamma curve are displayed. Those colors that are displayed do not remain constant as the brightness is changed, especially when going from its brightest setting down to a much lower setting.

You are better off calibrating at the brightness level you intend to be working in.

 

[Pictus]

No. If you want the most accurate colour you will set your brightness to about 120 cd/m2, or depending on your calibrator, it will do it for you.

120 cd/m2 is not the most accurate color...
http://www.luminous-landscape.com/tutorials/why_are_my_prints_too_dark.shtml
"Many new LCDs will have difficulty being driven much lower than around 120cd/m2"

http://www.dpreview.com/forums/post/40306131
"Eizo ColorEdge ($2000 for 243W): Also an excellent panel.
Good performance down to 120 cd/m2, but works best at 135+

 

[Pictus]

8500 is too off...
Argyll+dispcalGUI can do a better calibration and it is free...
If it is a TN LED panel will need to load a correction matrix, probably
will be something like "White LED something"

If it is for web, the default is 6500 gamma 2.2 or sRGB
If it is for soft proofing you need a better monitor, anyway check here .

 

[SpyderDoom]

8500 is too off...
Argyll+dispcalGUI can do a better calibration and it is free...
If it is a TN LED panel will need to load a correction matrix, probably
will be something like "White LED something"

If it is for web, the default is 6500 gamma 2.2 or sRGB
If it is for soft proofing you need a better monitor, anyway check here .

Thanks for the suggestions, Pictus. I can see you are a very experienced member.

I'm gonna try Argyl+dispcalGUI tonight. If I got this one right, I have to install new drivers for my Spyder 4 first. By the way, how will I ever know which calibration is most accurate? Will I get smoother grey gradients? I don't have a proper light source to check against prints at the moment.

The display we're talking about is the LG W2486L, the first TN LED panel from LG. It was so overhyped back in 2010 that I fell for it. It's fast and great for gaming, though. According to Spyder4Pro advanced analysis, it can reach an eye burning brightness of 290 cd/m2 with a contrast of 780:1 and 8900K color temperature. Which is far from ideal for photo work... :s

My older LG L1780Q has a native white point of 5800K, 110 cd/m2 max brightness but only 250:1 contrast. Still, despite being dim and low-contrast, I guess it's a lot better for photo work. However the CCFL adds a bit of a greenish tint that the calibrator doesn't seem to correct.

I don't have soft proofing in mind. I just want to see accurate colors, shadows, highlights and smooth gradients. This applies to web, photos and movies. I just like to see everything the way they were intended to be seen. My Canon Pixma MP640 makes great prints with genuine inks and papers. They almost match what I see on screen now, but for the color temperature. Most people though admit that my photos looks a lot better on paper.

What other software options do I have for this colorimeter? I've also read about HCFR, but is that mainly for TV calibration? I already own a Digital Video Essentials disc and it would be awesome if I could use the Spyder4 with it. However, to tell the truth, it looks like it has a steep learning curve...


Thank you everyone once again for your invaluable help!

 

[Ron AKA]

Have you considered just following the instructions that came with your Spyder4?

 

[Pictus]

I am glad to help, but sadly you are not going to have a smooth gradation
with this monitor as it is a "crazy/old" 6-bit+FRC TN panel...
You can change the monitor RGB settings to 6500K gamma 2.2 ?
If the monitor state is +- the same as the calibration goal
you will have a smoother gradation, the bigger difference
the worst gradation will be.

Here a clean gradation and a noise gradation that is more forgiving.

Your old LG with 5800K 110 cd/m2 + 250:1 is much better, I would try to calibrate
keeping its native state.

There is no better option than Argyll+dispcalGUI and it produces better calibration
results as possible as the hardware permits, smoother gradations and the neutrals will
be more neutral, but it will not transform a bad monitor into a good one.

Here an +- updated tutorial , I do not know what type of profile will be better for you, so
for start create a "XYZ LUT+matrix" then profile again(do not need to recalibrate) and create
a "Curves + matrix" and a "Single curve + matrix", keep selected the "Embed calibration curves in profile" and do not select the "Reset video card gamma table".

 

[SpyderDoom]

Wow! What can I say about this software? I am very impressed with dispcalGUI!





I don't know about the Elite version, but Spyder4Pro software doesn't even come close to dispcalGUI. My monitor looks so much better with dispcalGUI. Reds are not oversaturated (ie notification bubbles in facebook) and grey tones are the most neutral I have seen in this display. Clean grey gradients may not be completely smooth, but they don't appear to have any color banding -- at last! They are the smoothest gradients I have ever got with a calibrated screen.





The downside, this was no 5 minute calibration. It took close to an hour to complete. I started a second one using the color correction from the Datacolor software and then I went to sleep. I just woke up and I'm really really happy with the results! Please take a look at my settings and results:

Also this is the first time that this panel scores 96% sRGB coverage. With Datacolor's software it used to be 93%.

Here an +- updated tutorial , I do not know what type of profile will be better for you, so

for start create a "XYZ LUT+matrix" then profile again(do not need to recalibrate) and create
a "Curves + matrix" and a "Single curve + matrix", keep selected the "Embed calibration curves in profile" and do not select the "Reset video card gamma table".

Thank you for all the links you have provided so far. They're so useful. Regarding this last bit of advice, how will I know which profile would be best for me after calibrating with these 3 settings? Should I use HCFR to test the results?


Guys, you are all amazing in this forum!

 

[SpyderDoom]

I have also noticed that Datacolor's software produces darker shadows than dispcalGUI. As if the gamma near black is higher. Has anybody else noticed it, too?

 

[Pictus]

Your are welcome, check http://dispcalgui.hoech.net/#settings_profiling
Go to go to menu Tools>Verify profile, the LUT will give better results on the test,
but that do not mean that a real image will be better as it may be too rash with worst
gradients, if the monitor response is linear one of the matrix profiles will be
better, if it is not then the LUT may be better, between the matrix ones one may have
better color and the other may have better neutrals, my way is look at the gradients
and choose the profile with better neutrals and less banding.

It is better to not set the luminance value at the "White Level" as it make you lost
contrast, use the monitor brightness control for that.

The Datacolor software may be crushing the blacks...
The “Black point compensation” in Argyll/dispcalGUI is to avoid that.

 

[SpyderDoom]

Thank you very much. I will recalibrate tonight making use of your suggestions.

 

[Pictus]

Thank you very much. I will recalibrate tonight making use of your suggestions.

You are welcome, but do not recalibrate, just create new profiles...

 

[Pictus]

Thank you very much. I will recalibrate tonight making use of your suggestions.

You are welcome, but do not recalibrate, just create new profiles...

Ahhh, if change the luminance value at the "White Level", have to recalibrate...

 

[SpyderDoom]

Good morning!




I just calibrated again using the settings below:

I noticed than when I select the profile from Windows Color Management settings or whenever Windows boots to desktop my gamma curves look like this:

Whenever I start dispcalGUI the calibration curves get smoother and look like this:

It's not only the curves, but grey gradients look better, too.





What is going on here? How do I get to keep the smoother curves permanently?

 

[Pictus]

Hi, make sure there is no other LUT loader like the one from Datacolor.
Look at the Logon TAB in Autoruns.

If you run dispcalGUI as an administrator, will have the option to
“Let the operating system handle calibration loading”

 

[SpyderDoom]

Nope. No other LUT loader at startup. I have disabled Spyder Utility. Windows loads the correct profile. It just seems that dispcalGUI makes those curves a lot smoother. As if the ICM file stores low-res data that results in step-like curves. Profiles created by Spyder4Pro software are just like that, too. dispcalGUI makes the curves smoother when it loads. The same gamma curves.

 

[SpyderDoom]

I have also noticed that Datacolor's software produces darker shadows than dispcalGUI. As if the gamma near black is higher. Has anybody else noticed it, too?

The Datacolor software may be crushing the blacks...

The “Black point compensation” in Argyll/dispcalGUI is to avoid that.

Never mind... I found what was going on. dispcalGUI was using the sRGB tone curve which approximates 1 near the black point, making shadows brighter. It's doesn't have a gamma of 2.2 across the whole range.

Now the question is: calibrate to 2.2 or sRGB?