Blurry Display (Panasonic TC-L42E60)

James Cloos cloos at jhcloos.com
Wed Jul 10 03:43:59 PDT 2013


>>>>> "SB" == Steven Blatchford <sblatchford at gmail.com> writes:

SB> new 42 - http://sprunge.us/LASN

Looking at that, I may have misread the previous log.

In any case, that log shows:

[    40.880] (II) intel(0): Output LVDS1 using initial mode 1366x768
[    40.880] (II) intel(0): Output HDMI2 using initial mode 1920x1080
...
[    40.883] (II) intel(0): Allocated new frame buffer 1920x1080 stride 7680, tiled

and:

[    40.880] (**) intel(0): DPI set to (52, 52)

52 dpi at 1920x1080 is 42 inches.

There is also:

[    40.891] (WW) intel(0): Option "PreferredMode" is not used

so it didn't need that to do 1080p on the tv.

This log shows hdmi2 connected to a tv which has manufacturer MEI, which
is Panasonic.  I forget already whether the Panasonic was new or old.

If so, maybe the bluris the opposite of what I earlier presumed.  Is the
system trying to mirror the internal display on the tv?  If so, and if
it keeps the tv in its native 1080p, then it would have to use the gpu
to scale the 1366x768 to 1920x1080.  Perhaps the old 42 was receiving
1366x768 and doing a better job scaling that than the gpu does?

Setting the external, eg, leftOf the internal ought to avoid that.

As should disabling the interal when the external is connected.

But it looks like the panasonic is working as it should.

Oh, and look in a magnifying glass at the 42's pixels.  Many at that
size use bayer pattern sub-pixels.  Avoid sub-pixel fonts at all costs
on such a display.  Plain grayscale anti-aliasing is fine; sub-pixel is NOT.

-JimC
-- 
James Cloos <cloos at jhcloos.com>         OpenPGP: 1024D/ED7DAEA6


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