Calibrating the BenQ 27 Display for gray neutrality

[deanwork]

I recently bought the BenQ Sw2700PT pro display to do critical color work with.

I have been very happy with it. It has very consistent illumination across the plane and I have no complaints for working with photo printmaking.

This was calibrated and tested in various ways, but primarily with my I1 Pro 2 spectro and I ended up using the X-Rite Software and tweaking the result with the BenQ softare.

I use the Atkinson printer evaluation target to compare the image to print and the on screen image to my other display, the Nec PA271 calibrated with the Nec Spectravision software.

Both of these displays show the same hues of the target, same contrast and the same saturation of colors. What is differient is the neutrality of the gray images. I notice this on the large neutral black and white steel ball image in that target. The BenQ is a cooler gray, tending very slightly toward magenta, where the Nec is apparently neutral.  My NEC is 7 years old though. This is probably not going to effect my printing since I don't soft proof the hue of black and white prints, and the color work is fine. It just kinda of bugs me.

Does anyone know a way to tweak the gray neutrality of this display without adversely effecting the rgb color content?

I like this display enough to order the new 4K 32 inch version. The price is definitely right.

[CeeVee]

I see about $800 for the BenQ 32" 4k monitor at various vendors.

[rasworth]

The BenQ software and X-Rite don't mix together very well, for the following reasons:

1. Palette Master Elements loads up the 2700 internal LUT as part of its profile generation process.  The profile is intended to work with a "straight line" load in the pc/mac video adapter, even though it contains a vcgt tag field, which is normally downloaded to the video adapter at logon.  I examined the table, it's "almost" a straight line, but I took no chances and disabled the calibration loader from X-Rite, to ensure an unmodified LUT in the video adapter.

2.  X-Rite always modifies the video adapter LUT as part of its profile generation process.  I experimented with using it after doing a Palette Master Elements load, setting everything (except gamma) to native.  This worked ok (had to enable the calibration loader), but gave no better results than the BenQ software.  The X-Rite vcgt tag was essentially linear, a good thing since it verifies the original calibration into the 14 bit LUT of the 2700 was done correctly.

3.  After bouncing back and forth, I ended up with only using the BenQ software, with the calibration loader disabled.

I guess I'm implying that perhaps your neutral tinge may be do to with mixing the software results improperly.  I see no way where on can profile with X-Rite, and then "tweak" with BenQ afterwards and achieve accurate results.  The only combination of the two that I could make work was to use BenQ first, setting the 2700 LUT to the desired curve, and then x-Rite afterwards, using only the X-Rite profile, i.e. discarding the BenQ profile.

Richard Southworth

[deanwork]

Thanks Richard,

What gray gamma setting are you using. I was using 2.2. My grays were slightly dark also so I was trying to "tweak" the black point slider with the Ben Q. software.

I don't understand why you would choose the BenQ software over just using X-Rite.
How do you disable the calibration loader when using their software?

I have been getting essentially the same results as well with both software workflows, and that is, a not perfectly neutral gray image but everything else really good.

Sorry I meant to post this on the color management list.

john

The BenQ software and X-Rite don't mix together very well, for the following reasons:

1. Palette Master Elements loads up the 2700 internal LUT as part of its profile generation process.  The profile is intended to work with a "straight line" load in the pc/mac video adapter, even though it contains a vcgt tag field, which is normally downloaded to the video adapter at logon.  I examined the table, it's "almost" a straight line, but I took no chances and disabled the calibration loader from X-Rite, to ensure an unmodified LUT in the video adapter.

2.  X-Rite always modifies the video adapter LUT as part of its profile generation process.  I experimented with using it after doing a Palette Master Elements load, setting everything (except gamma) to native.  This worked ok (had to enable the calibration loader), but gave no better results than the BenQ software.  The X-Rite vcgt tag was essentially linear, a good thing since it verifies the original calibration into the 14 bit LUT of the 2700 was done correctly.

3.  After bouncing back and forth, I ended up with only using the BenQ software, with the calibration loader disabled.

I guess I'm implying that perhaps your neutral tinge may be do to with mixing the software results improperly.  I see no way where on can profile with X-Rite, and then "tweak" with BenQ afterwards and achieve accurate results.  The only combination of the two that I could make work was to use BenQ first, setting the 2700 LUT to the desired curve, and then x-Rite afterwards, using only the X-Rite profile, i.e. discarding the BenQ profile.

Richard Southworth

[rasworth]

2.2.

You have no choice but to use the BenQ software to load the 14bit LUT in the 2700, in either Cal1 or Cal2 mode.  The software creates custom channel curves, using your choice of gamma, white point, and maximum luminosity.  Once this is done you can switch over to X-Rite if you prefer, go thru the normal process and use their profile instead of the one generated by BenQ.

I disabled the X-Rite calibration loader, there because previously with my Win 10 system I had used X-Rite, by going to task manager, startup, and disabling the calibration loader.  In Windows you also have to pay attention to the system color management settings, make sure the profile of choice is set as the system default.

Another approach is to use one of the other modes available in the 2700, and build a profile with X-Rite in that chosen mode.  I wanted very specific brightness and white point, so I took advantage of the cal modes, which can only be loaded via the BenQ Palette Master Elements software.

It's a little confusing as compared to using most off the shelf monitors, in that you have complete control over the channel curves if you choose to go that route.  So you end up concerned with two LUTs, the 14 bit version in the BenQ, and the (normally) 8 bit one in the video adapter.

Richard Southworth