8347 Views 9 Replies Latest reply: Dec 23, 2010 6:34 PM by Rimbault
Exact same problem here ...
I have an Optoma HD 20, and I try to connect it to my MBP with a Mini Display to HDMI adapter.
The screen would only go between normal and blue .... as yours ...
Note that I tried today with another projector and a MiniDisplay Port to VGA adapter and it worked fine.
So now i'm lost ... Is the problem the HDMI adapter or the Optoma ?? Don't know .
If someone could help us, I would really appreciate.
By the way, French ?
Ce serait quand même une sacre coïncidence .... même machine, même problème, même jour ...
So now we are two...
I didn't fix the problem, I was thinking maybe try with MiniDisplayPort to VGA, but I have to buy a new adaptater. Did you also try it on your Optoma ?
I am wondering if the problem is a compatibility issue of frequency between MBP and Optoma via HDMI.
PS : Oui français, c'est effectivement une drôle de coïncidence. En espérant que l'on trouve la solution...
I use my macbook pro on digital cinema projectors, I can plug directly in via DVI but have run through may scalers. I had a problem with HDMI when using a scaler, it turned out that HDCP was the problem but not from my mac it was the projector/scaler not willing to playback the image without HDCP. With DVI and VGA you should not have these problems.
The mac is great as its one of the only computers i have had to be able to run 2048x1080 as a second desktop but even with some very expensive scalers my mac wont run this high, i tend to plug directly in to the head via DVI.
I don't know if there is an other solution, the only thing I found is to use VGA. I get Full-HD resolution (1920 * 1080) but I got some issue sometime with this resolution... like radio-interference... but maybe it's because of my audio system.
Works well with the same resolution of my Macbookpro (1280 * 800).
I have found VGA can have problems with grounding issues, having a mac and projector plugged in to 2 different power supplies can mean you have 2 different earths, you get this a lot with sound, you could try running off the battery and this would show if that is the case.
It would be interesting if getting a DVI to HDMI convertor would work, so mini display to DVI, DVI to HDMI in to the projector.
I have to say im not 100% on the inner workings and how mac's deal with HDMI and HDCP but from the experience i have had with Cinema digital projectors and high end scalers i dont have any problems with DVI but have had problems with HDMI.
There are three things you may consider in the Displays preferences: resolution, refresh rate, and Underscan. With no image showing, I would check the refresh rate first: details should be in the handbook of the projector. Have you also checked the cable/connector with another unit (say a TV) to make sure there is no problem there?