Blue translucent screen on HDMI output

[Cubytus]

Hi there,

I was sure this problem was tackled since it first appeared, but apparently not. I plugged in a MBP, late 2011 issue, to a 1360x768 TV through HDMI connection, and got a translucent blue screen both on the TV and MBP. Translucent because on sticking my nose to the screen, I could indeed see the windows "behind" it.

From one try to the other, sometimes I got "Not supported" displayed on the TV, as if I selected the wrong resolution. During this time, nothing showed in the Console.

I also tested the VGA connection on the same TV, but it failed to be detected, however.

On connecting a MacBook to the MBP through screen sharing, I could see plugging in the TV was correctly detected, and the correct resolution sent. I could even slide the "overscan" slider and see the blue rectangle changing in size accordingly. If that's interesting, when I unplugged the TV from the MBP, sometimes it kept the "Disposition" tab in the Monitors pane, as if more than one monitor was plugged in.

I already tried doing a deep clean on startup with AppleJack, to no avail.

Then I reversed the roles: the MacBook (late 2009) was plugged in the TV, MBP controlled its screen, and the exact same signes appeared, although they were running different OS X versions (MBP on Snow Leopard, MB on Yosemite beta) and had, obviously, different adapters.

FWIW the TV itself does work, as I could play a movie without a problem with a Raspberry Pi.

As there are no messages in the Console, what could be the problem, then?

 

[joecool99]

it could be issue with GPU or the external output port. can you try it with a display?
try PRAM + SMC reset first

 

[MagicBoy]

What size 2011 MBP?

Does the 2009 work fine directly connected to the TV? I got lost in all the screen sharing bit - the OP is not that clear.

 

[Cubytus]

What size 2011 MBP?

Does the 2009 work fine directly connected to the TV? I got lost in all the screen sharing bit - the OP is not that clear.

Both 13". None could send a valid picture to the TV. If Yosemite beta could have been blamed because of its beta status, the MBP is stable.

 

[Cubytus]

Just reset the SMC. I only remembered about the PRAM.

Now I get a picture from the MBP using both adapters.

Since I was close to the screen, I could see the image is much sharper with the VGA adapter than the HDMI one at the same resolution. Shouldn't it be the opposite?

 

[CaffeinatedNoms]

Since I was close to the screen, I could see the image is much sharper with the VGA adapter than the HDMI one at the same resolution. Shouldn't it be the opposite?

Not necessarily. Some TV's apply automatic filtering to HDMI (and some of them, I type whilst glaring at my own TV, don't have options to turn that off) that smoothen images to hide artefacts or upscaling problems - but they will assume you're connecting a PC when you use the VGA port and so not filter the image.

 

[Cubytus]

Surely this entry model doesn't have such an option.

I though the problem was gone after SMC and PRAM were reset, but just as I wanted to plug it in for a movie, I got the dreaded "Not supported" message on the TV on HDMI, and "No signal" on VGA. Rebooting the MBP with TV attached did give a picture.

What could be going on?