9 Replies Latest reply: Dec 23, 2010 6:34 PM by Rimbault
Juliend3 Level 1 (0 points)

I am trying to display my computer on my videoprojector, Optoma HD200X, but it doesn't work. The MacbookPro is trying to detect the monitor but failed. The screen of the MBP become blue and get back to normal, and become blue again...

I bought it on april 2010 (new model). I am using a MiniDisplayPort to HDMI adaptater to connect to videoprojector.

My laptop works fine with the same adaptater on an external display, and the video projector works fine with the same HDMI cable and a PS3.

Is there something I can do to fix this problem ? I try with different resolution.

Thanks for your help.

Macbook pro 7,1, Mac OS X (10.6.5)
  • Rimbault Level 1 (5 points)
    Hello Julien,

    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 ...
  • Juliend3 Level 1 (0 points)

    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...
  • boontech Level 1 (5 points)
    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.
  • Juliend3 Level 1 (0 points)
    So I just bought a MiniDisplayPort to VGA adaptater and it works well on my Optoma HD200X video projector. It's so bad not be able to use HDMI, and to have to buy a new adaptater (not for Apple...).

    Thanks for your help.
  • iacopoenbarna Level 1 (0 points)
    I'm in the same situation as you. Just got an optoma HD20, connected it to the macmini via HDMI (used to be connected to an HD TV and worked perfectly) but can't see a thing. Is the only solution then to use VGA? What sort of resolution do you get? Can you see HD movies for instance?
  • Juliend3 Level 1 (0 points)

    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).
  • boontech Level 1 (5 points)
    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.
  • Graham K. Rogers Level 5 (5,430 points)
    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?
  • Rimbault Level 1 (5 points)
    So did I, it work great for me too now.

    The only issue was getting rid of the 25" hdmi cable on replacing it with the VGA cable

    Thanks to all of you for the input.