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View Full Version : Color problems with DVI/HDMI link from Mac Mini to HDTV




tarasis
Nov 10, 2010, 03:16 PM
I recently bought a 50" Plasma (LG 50PC51 which appears similar to the LG 50PC55 & 50PC5D, but was for sale only in Germany) which is 720 (1366x768) and I'm having problems with the colors when connected to my 2009 Mac Mini.

When I connected via VGA (as I hadn't yet got a DVI to HDMI cable), it worked though the VGA Display profile seemed milky (the black was much greyer than the black via the Xbox) and muted. I had to opt for 1280x768. (60Hz) and the picture was muted/dull.

So I ordered an DVI to HDMI cable, as I already had a Mini DVI to DVI adapter. That arrived this morning but I was very disappointed by the results. The mini now detects its an LG TV and auto selects the 1360x768 (59.8hz) res (other options in the drop down are 1280x720 60 Hz (NTSC Television) and 1080i (Pal Television)).

Quality is okay for x768 and x720, in terms of sharpness, but the colors are something else completely. The banding in things like Finder & Transmission where the entries alternate between White and a light Blue are instead a grey and whats looks like a silvery white. The preferences dialog (like for Display options) is a light grey and a slightly darker light grey but nowhere near the normal shades.

I found this thread elsewhere about some HDTV's only accept a limited RGB output http://forums.plexapp.com/index.php/topic/6308-rgb-color-output-limited-range-16-235/ and the 2009 Mac Mini's don't seem to send that limited range.

Using the tool mentioned in the thread (Black Light (http://michelf.com.nyud.net/projects/black-light/)), it fixes the regular desktop somewhat (banding looks roughly correct) though its still not ideal. (Browns can be overly red, red a little punchy and yellow a little muted - though that might be the telly itself).

Wondering what my options are, apparently the 2010 Mini will handle the limited RGB output, can anyone confirm that? I would consider that AppleTV2 but my hifi doesn't support Optical (at present I route sound through my hifi, not the TV) but if the 2010 mini alleviates that problem I'd be willing to sell my 2009 mini. I'm surprised at the preformance given a number of people seem to use Mini's for home theatre media boxes :(

[EDIT] Minor aside, one interesting thing I've noticed is that the Mini boosts the colors as Quicktime or iTunes starts playing a video. Soon as you close the video playing window it stops being bright and becomes muted again. ---- Actually this seems to be the TV, with half the TV's menu on screen, the screen is a dimmer but when you go onto the next part (and it fills the screen) the colors / brightness is boosted, even picture mode is on "Standard" and not dynamic.

Also while VGA mode works, its very muted and not as sharp