Luminous Landscape Forum

Equipment & Techniques => Computers & Peripherals => Topic started by: walter.sk on December 24, 2008, 09:42:50 am

Title: NEC 3090 Banding: Significant or Pixel Peeping?
Post by: walter.sk on December 24, 2008, 09:42:50 am
I have my NEC 3090WQXi calibrated and profiled with an i12 colorimeter and SpectraViewII with the following parameters:  D65(Target 6506K, Calibrated 6573K, Delta E 0.53);  Luminosity Target 140 cd/m2, Calibrated 140.1; Black Point native: 0.43, calibrated 0.63;  Contrast Ratio 218:1; gamma 2.2;  Color Tracking Delta E 0.41.

Other settings:  Primary Color Chromaticity: Use Factory Measurement; Calibration Priority: Best Grayscale Color Tracking; Color Correction (Uniformity across the screen): Maximum.

I have tried various luminosity settings from the current 140 cd/m2 down to 90 cd/m2 and back up, in increments of 5.  While 140 is still slightly too bright, my prints are accurate in color but very slightly darker in my normal viewing light.  I am anticipating buying a dimmable print viewer (either the Just Normlicht Color Master 2 DI or what appears to be a very similar GTI PDV 3ED.  The GTI is about $100 more than the Just, and I am tempted to go with the Just, which looks to be a company as involved in professional color-critical applications as GTI...any thoughts on this?)

I decided to try some black-white gradients, both vertical and horizontal.  At 100% I could see what I consider to be mild banding, more evident in the darker values.  The banding was on the vertical as well as the horizontal gradients.  The banding became more pronounced viewing at 200% and 300%. The banding occurred whether or not the gradients were done with dithering.

Is this normal for an NEC 3090?  Does it also occur on LaCie and Eizo monitors of similar specs?  Or am I being an obsessive pixel peeper?  I have not noticed banding in the images I process on this monitor.
Title: NEC 3090 Banding: Significant or Pixel Peeping?
Post by: richardhagen on December 24, 2008, 11:02:31 am
Quote from: walter.sk
I have my NEC 3090WQXi calibrated and profiled with an i12 colorimeter and SpectraViewII with the following parameters:  D65(Target 6506K, Calibrated 6573K, Delta E 0.53);  Luminosity Target 140 cd/m2, Calibrated 140.1; Black Point native: 0.43, calibrated 0.63;  Contrast Ratio 218:1; gamma 2.2;  Color Tracking Delta E 0.41.

Other settings:  Primary Color Chromaticity: Use Factory Measurement; Calibration Priority: Best Grayscale Color Tracking; Color Correction (Uniformity across the screen): Maximum.

I have tried various luminosity settings from the current 140 cd/m2 down to 90 cd/m2 and back up, in increments of 5.  While 140 is still slightly too bright, my prints are accurate in color but very slightly darker in my normal viewing light.  I am anticipating buying a dimmable print viewer (either the Just Normlicht Color Master 2 DI or what appears to be a very similar GTI PDV 3ED.  The GTI is about $100 more than the Just, and I am tempted to go with the Just, which looks to be a company as involved in professional color-critical applications as GTI...any thoughts on this?)

I decided to try some black-white gradients, both vertical and horizontal.  At 100% I could see what I consider to be mild banding, more evident in the darker values.  The banding was on the vertical as well as the horizontal gradients.  The banding became more pronounced viewing at 200% and 300%. The banding occurred whether or not the gradients were done with dithering.

Is this normal for an NEC 3090?  Does it also occur on LaCie and Eizo monitors of similar specs?  Or am I being an obsessive pixel peeper?  I have not noticed banding in the images I process on this monitor.


at the photoplus show in nyc eizo had their 30 inch monitor showing a vertical grayscale. it definitely showed banding across the whole spectrum. i even brought it to the attention to one of the sales people who sorta made nothing of the matter. having seen this made me think that eizo was not the panacea of monitors.

rh
Title: NEC 3090 Banding: Significant or Pixel Peeping?
Post by: digitaldog on December 24, 2008, 11:23:03 am
To view banding, you need to assign the display profile to the test doc. Then banding is the result of the video system.
http://www.ppmag.com/reviews/200412_rodneycm.pdf (http://www.ppmag.com/reviews/200412_rodneycm.pdf)
Title: NEC 3090 Banding: Significant or Pixel Peeping?
Post by: walter.sk on December 24, 2008, 07:38:46 pm
Quote from: digitaldog
To view banding, you need to assign the display profile to the test doc. Then banding is the result of the video system.
http://www.ppmag.com/reviews/200412_rodneycm.pdf (http://www.ppmag.com/reviews/200412_rodneycm.pdf)

Thank you, Andrew!  The missing pieces in my "pixel peeping" were that I had been using ProPhoto RGB rather than Adobe RGB (duh!), and had not assigned my monitor profile.  As soon as I did those steps, the banding disappeared to the point where the gradient seemed nice and smooth.  At a couple of points I could vaguely detect a hint of banding, but I am not even sure whether I actually saw it, with my eyes about 2 inches from the monitor screen.  

I also saw the first hint of separation when the lower point on the curve was at 3.  I am not particularly shocked by that, as the NEC 3090 uses an H-IPS panel, which does not have the blackest of blacks as its native black point.

I did notice another artifact when viewing close up.  While the steps between 3 and 255 were all neutral in appearance, I noticed when my eyes were close to the monitor a vague speckling of tiny magenta points.  This seemed to be not a color cast per se but appeared like something sparkly from "behind" the screen.  At my usual viewing distance I saw only neutral tones from black through grays to white.  Could this be inherent in the H-IPS screen?