Wednesday, February 19, 2014

Graphic Arts Workstation - Part 4 : Monitor Banding and Other Tests

I received several emails with questions on the DreamColor display. I'm very pleased with it. It has, as I've said, eye-numbing clarity and brightness. Yea, maybe a bit too bright. I'll have to look into that some more. It is easy to tune it down a bit. At this point in my life I'm not as hung up on following absolute standards like ProColor or whatever you prefer. I just don't have the professional nor amateur need to do so. And also as mentioned in prior posts. my right brain has managed to take almost complete control of my home PC. Consequently, I have little patience any more for just sitting around tuning my technology unless my right brain says it needs something.

But, nonetheless, am perfectly willing to help out others who may want to dive deeper into a topic or just ask a few questions on just how good the DreamColor is. And to that end I'll explore the topic of gradation and banding. This is a pet-peeve area for even my right brain. I hate watching movies on my 45 inch plasma and see all those gradations in the shadows. It drives me nuts, and ruins the whole experience... albeit momentarily.

The last place I want to see banding is in Photoshop when I'm processing one of my images.

So with that in mind I decided to do some tests. I propmptly went into Photoshop CS4 64 bit version and did a black to white gradation... don't laugh. Of course, it was all sorts of  banded. Yea, I could dither or a half dozen other smoothing tricks, but that's not really the solution is it.

Besides, if I'm sharing ideas with others we need a standardized methodology. So, wha-la... just Google gradient test and you'll find some. Without too much critical thinking I choose the site

I then ran the gradient test on both my DreamColor Display and my Asus ProColor.

First the ProColor

The card is the NVIDIA Quadro FX 560 with the 307.45 driver & bios 5.73
128Meg memory, 1920 x 1200 x 4 million color , 24 inch display
It is currently set to the factory settings for the Adobe RGB mode.

The Lagom gradient test was absolutely smooth. But the blacks were not as rich as the DreamColor. For the Black Level test I could see all the squares except the first one. The background did seem to be absolute black.

Interesting... I ran the test from the DreamColor laptop onto the ProColor external monitor, basically letting the Laptop's newer card drive the external monitor.

The results were very similar. The ProColor is indeed a nice monitor for the price.

Now for the DreamColor

The card is NVIDIA Quadro K610M with 312.56 driver
8.8 Gig Memory, 1920 x 1080 x , 32bit color deptt, 17 inch display
Using the HP Calibration Kit mentioned in prior posts it is set to :
Tone Response Curve : 2.2
ICC Profile Version : 4
Achive Luminance value using video LUT's = True
White Point : x: 0.313  y: 0.329
Luminance: 120
Gamma : 2.2
The Display Preset : AdobeRGB

The visual examination of the Lagom gradation test was a bit disappointing. There is one somewhat distinct band on the very dark end. It is where it going from the darkest possible to some small variation above that where it banded one time. Everything else is perfectly smooth.

The other test of note is the Black Level test. On that test I was not able to see the squares 1-10. That seems pretty significant, and I guess I now have to play with the calibration, or, just make manual adjustment to try to get something better than that.

If anyone has other requests for testing let me know.

Further Testing The Following Day

Yesterday's testing left me with a couple of questions. The first question is the preset I've chosen. AdobeRGB really isn't the best to be working with when you consider the advances in technology. The other question that remained was the driver for the Nvidia card. There are a lot of reports that banding is a common problem.

To resolve the second question I downloaded new drives for the card from both HP and the absolute newest (nonOEM) driver straight from Nvidia. Neither driver fixed the banding, and the nonOEM driver made the HP Calibration Kit dysfunctional with an error message "“Failed to read the prescriptions" and promptly became unusable until I reloaded the new HP driver.

I'll wait for HP to create a new driver to fix the banding.

I also upgraded the test.  For this series of tests I used a 10bit gradation file which can be found at Image Science (

I followed the instructions to insure that Photoshop (PS) was set to use a 10bit file, and it was. The results were a consistent banding across the whole gradation. If I changed PS from 16 bits per channel to 8 bits the banding went away completely.

Just for grins I booted up my old 32 bit XP system with Photoshop on it to see how it would display the gradation on the Asus ProColor. That system has an Quado FX 560 with 128Meg. It actually wasn't that bad. It is running a 32 bit version of PS (versus 64 on the zBook), and the bands were slightly less pronounced and there were fewer larger bands.

Using the HP Mobile Display Assistant you can quickly flip through various color space settings. I ran through them all and non of them had a dramatic affect on the banding. The DCI-P3 seemed to clear up banding the best, but it was also the darkest, and because of that harder to see if there was banding.... and, of course, not a color space for a photographer to use.

All in all, my right brain is beginning to get a little tired of this, because it is all about color lots of variation, and lots of detail.... and all this banding issue is never going to show.... never.

I don't think I'm heading for a Rothko depression period where I'm enveloping myself in fields of darkness.

But nonetheless, the left brain wants to know that my investment is performing properly... whether I ever need it or not.


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