Difficulty with projectors!

Trying turning the computer off, then turning it on with the cable connected to force it to recognize the projector. That has worked for me before.

Go into display preferences then click Detect Displays. It should force it to find the projector.

Nope - I'll second this problem. Over the past week, I've tried two different MBPs (2.4 15"), two different projectors (Boxlight XD-17k and a Sony?), two different cables (DVI**2 and DVI/VGA w/ adapter), every resolution, color depth, frequency, method (mirror vs tile), and protocol (boot connected, closed, alternatively power cycle, etc.). The ONLY resolution that I get ANY response at is 1024x768, thousands of colors, 70 Hz, DVI/DVI - and at that resolution, the projectors blink (auto detection) but never actually sync up or display any video. Threads I've found here and elsewhere tell me I"m certainly not alone? Why is there so little info on this topic?

Perhaps because it is relatively rare? I used my MacBook and never had problems connecting but I know two of my colleagues did. In one case we discovered it was a cable problem and in another it was the dongle. I'm not trying to claim people aren't having problems but it is possible they are rare.

I have been having similar problems (see post http://discussions.apple.com/thread.jspa?messageID=8067659&#8067659).

Sometimes the MBP will not detect an external monitor; nearly always it won't detect an external projector (3 out of about 30 times it did manage it). A restart will always get it to detect, but this is a pain when you are in a hurry to start a lecture.

Now: I tried an archive and install: no change. I had a logic board replacement: no change. I have just done a complete wipe of the hard disk and reinstall without migrating anything over from the old system: no change!!!

What is going on?

I have a 2.4GHz Core 2 Duo and tried connecting it to an Epson projector in my class today and only my desktop wallpaper showed up. I'm using a DVI to VGA male to male cable.

The folders on my desktop don't appear and the dock isn't there. The only thing (aside from the wallpaper) that appeared on the projector was "System Preferences" after I clicked on it. But all the screen sizes had a GHz at the end. When I clicked on "Detect Display" nothing happened, either.

It is very frustrating because I have a class presentation powerpoint on Monday morning with a laptop that fails to cooperate. Until today I did not know of this problem. If I used a Macbook, would the problem occur? I can borrow one but won't have access to the overhead projector until Monday morning. So I'll be praying that something works out.

Message was edited by: Okeetee

Message was edited by: Okeetee

Oketee,

If you turn "Mirroring" on in the display preferences, you'll see see the same thing on both screens. The way you have it set up now is extended desktop mode--it's supposed to look like that to give you more screen real estate.

Hi Krypttic,

Thanks for the response! "Mirroring" is accessed through "Detect Display," right? I don't recall that appearing after I clicked on "Detect Display" but I'll try again on Monday. Bummer that my class is locked until then.

Thanks again,
-Kyle

Open System Preferences, then click Displays and then the Arrangment tab. The "Mirror Displays" option is a checkbox at the bottom of the page. When you're not in mirrored mode, you can also move the two displays around to orient them any way you want. To put the menu and main desktop on one computer, grab the white menu bar with your mouse and drag it to the other screen.

krypttic,

Thanks for the help! I was able to successfully present my slideshow with the overhead projector.

I wonder if it is all that rare.'m experiencing the same issues (which is why I came across this discussion--trying to resolve the issue).

When I experience this issue, no amount of trying "discover displays" helps me. In fact, using "discovery displays" frequently locks up the laptop and I'm forced to do a "nasty" reboot--and of course crashing whatever I had open at the time, like Keynote, Pages, etc..

The only reliable "workaround" I have come up with thus far is to start with my MBP powered off, plug in my Apple video adapter, plug in the cable for the projector, then power up the MBP. It almost always works that way. Occasionally I may need to dumb down the MBP's video, sometimes as low as 800x600. Then the laptop will find and use the projector. Miraculously, my MBP's video will go back to its original setting--and the projector's video will go to its "normal" settings.

I train project managers (the PMP certification course is my specialty) and I'm using my MBP constantly, at various locations with various projectors. Most of the time the laptop detects the projector right away, but occasionally I run into the issue discussed here. When I do, it's frustrating, can be embarrassing (always, Always! setup early, before anyone is in the room!!)- and I really wish I didn't have to use the cold-boot workaround. It vexes me that my MBP just doesn't like some projectors and has to be forced to get along with them.

I'm in the same boat. I'm a professional speaker. Have been using Mac Laptops since the first one came out. This is making me crazy. And it makes me look unprofessional. I get in more than an hour early, just to set up the dang thing, and people are sitting waiting an hour later for the session to start, and we've got 6 people up front trying to make it "see" the projector. BAD press for Mac. Most of the people end up insulting my choice of computer.

The problem is (and this is a New MacBook 17" 1.2 Ghz Intel 2 Core Duo) -
I hook up the projector to my Mac, and the Mac goes to blue screen. There IS NOT a way to see the System Preferences. If I unplug the connector, I can see the screen. I try and click on Detect Displays just as I'm replugging in it. Nothin. And without a projector connected, there is no way to see the supposed tab that says Mirror or Arrangement. So I restart my laptop with it plugged in, nothing. Can't even see my sign in screen unless I unplug the connector. I have the right connector. They have working projectors. For the first time since 1984, I regret buying a New Mac. I was better off with my old reliable one. These "improvements" are not improving my computer experience. The only reason I own a laptop is to do these presentations. Bad apple!

Hi,

I am having problems hooking my Macbook Pro 2.55 with Snow leopard up to a Christie LX6500 by way of a DCS100 scan converter. This is for use in a large venue. We tried pretty much everything to get the computer to see the DCS100 scan converter. We are using the mini display port adapter to an HDMI cable. When we switch resolutions, I see the blue screen monentarily on the projection screen and then nothing.

Another person had an earlier version Macbook which saw the DCS100 scan coverter instantly. What could be going on and is there a way to solve this problem.

My Macbook pro sees my large screen external monitor with no problem.

Any suggestions?

It has been over one year since the question was posted, and recent posts show the problem still occurs. I want to add my voice.

This is one area Macs use to run circles around PCs. While my colleagues were always struggling to get their PC to talk to a projector (and set the resolution correctly), I connected my PBG3, PBG4 and MBP 2.4GHz (this one using a DVI-to-VGA adaptor) to any projector and it always worked. Sometimes I could further improve on the resolution and refresh rate that were selected automatically, but the initial setup was always decent. Sometimes I needed to click "detect monitors", but not always. I usually needed take no precaution. It was very rare that I had to put to sleep, connect, and wake the Mac. By the way, I always used extended desktop to be able to benefit from the presenter's screen offered by Keynote. To me, mirroring the screens has been an inferior solution.

I still connected without problem at a recent conference (after upgrading to Snow Leopard), but most projectors at my workplace give me difficulties now, even though I connected to the same projectors without a hiccup a few months before.

Usually the projector says "no signal" and it does not matter if I connect before or after turning the projector on (something I never even worried about before).

The last time I needed to connect to a projector at my work (Jan. 7 2010, the only way I could get it to work was to select mirroring with a resolution of 1024x768 at 60 or 70 Hz first, and then "detect monitors". Disabling mirroring, changing resolution, chosing higher frequencies or "detecting monitors" too early resulted in a "Signal not compatible" or a "no signal" message.

This is really annoying. As others have noted, it makes me look unprofessional. Often I was able to use my Mac at conferences that did not allow computer switching between talks because I promised I could switch computers very quickly. I can't dare make this promise anymore. I'll have to save my presentations to pdf and use a PC, losing some of the benefits from Keynote.

I notice that many of the posts here were made before Snow Leopard, but it is only recently I started having problems connecting to some projectors and I wondered if Snow Leopard was responsible. I am less certain since reading this thread, but then why is it that only recently I have been encountering difficulties connecting to projectors? I was about to say that my hardware has not changed, but the motherboard was changed in the summer under Apple Care, so strictly speaking my hardware did change.

Someone mentioned "bad cable" as a possible cause, so I'll try a second DVI-to-VGA adaptor soon and will report back.

Denis

I just wanted to add that I have absolutely no problems with external monitors. All are digital and plug directly in the DVI port. This makes my DVI-to-VGA adaptor a prime suspect, I suppose. As I said, I have another one that I'll try soon.

Denis