Which T510 / T520 display has best black value?

[ssd_thinkpad]

T510 and T520 have the same 16:9 display ratio. Which of these display offer best viewing angles and best black value. From a test I read that the black value of the HD+ is lower than of the FHD one. What about the HD display, could it offer the best black value of the three panels?

• 15.6" HD (1366 x 768)
• 15.6" HD+ (1600 x 900) [add $50.00]
  Information
  Maximum: 222 cd/m²
  Average: 202.6 cd/m²
  Brightness Distribution: 79 %
  Black: 0.39 cd/m²
  Contrast: 569:1
  http://www.notebookcheck.net/Review-Len ... 722.0.html
  Review from archer6: http://www.thinkpads.com/forum/viewtopi ... 45&t=85668
• 15.6" FHD (1900 x 1080) [add $250.00]
  Information LEN40B2
  Gossen Mavo-Monitor
  Maximum: 265 cd/m²
  Average: 237.2 cd/m²
  Brightness Distribution: 85 %
  Black: 0.47 cd/m²
  Contrast: 564:1
  http://www.notebookcheck.net/Review-Len ... 871.0.html

[Colonel O'Neill]

Possible, but I doubt it. The HD screen does suffer from a visible pixel grid, which sohuld be considered and probably avoided.

[ssd_thinkpad]

So the choice will be between HD+ and FHD. HD+ offers better contrast and black value where FHD has a more even backlight and more pixels. As I use Windows 7 to switch the DPI down, only contrast and black value concern me. Do you know of more tests regarding these displays?

[davidhbrown]

Interesting questions which I appreciate your bringing up before I automatically spring for the "best" panel, as I usually do.

I can see why you're interested in more tests. Looking at the distribution of brightness graphics in the notebookcheck.net articles you link, I wonder whether I mightn't find the side-to-side variation in brightness of the HD+ screen to be more of an annoyance when looking at dark images than the slightly higher black level of the FHD screen.

I wonder if you turned down the backlight level to drop the FHD's screen average from 237 to the 202 achieved by the HD+ screen, that's about a 15% drop. Its black level is about 17% higher, so you might come out about the same. Of course, if a ~15% drop in backlight brightness gets you into a zone where backlight flicker is annoying, that may be irrelevant (and I think there are other threads about that).

[ssd_thinkpad]

Does decreasing the backlight result in backlight flickering on some thinkpad displays?

[Colonel O'Neill]

Not that I can see on my X100e. T400 screen is no longer operational, but I don't recall it flickering.

[sarbin]

Does decreasing the backlight result in backlight flickering on some thinkpad displays?

never seen with decreased backlight on any of my thinkpad lcd panels, from 12" xga up to 15" qxga, 4:3 or widescreen, ips or tn.

[davidhbrown]

Re: no flickering; that's good to hear. I have yet to own a LED-backed notebook and given that I tend to run screens at rather low brightness levels -- my newish Dell U2410 desktop monitor is set to 0 out of 100 and when my T61p was new, I'd often have it around 7 or 8 out of 15 -- I have been a little concerned that pulse-width-modulation of the backlight would be more noticeable without phosphors to decay.

Re-reading the flickering threads on this board, it seems like people were seeing a mismatch between screen redraw rate and shutter speed on videos of computer screens. Sorry if I caused any concern here.

How about those black levels?