Dual Head and Triple Head issue

[kobrien]

Hello ,

 

I was wondering if there will be somebody who can help me. On the show I am currently working on, we are running catalyst version 4, from the cat we have four sanyo PLC XP56 lcd projectors. To output to each of these projectors we are using a DualHead2go analogue edition, and a TripleHead2go digital edition. The issue we are currently have is that we cannot get the catalyst to recognise that there is a DH2G and a TH2G running sometimes it will recognise one but not the other. It may be a case that we need seperate drivers loaded on the Mac but we are not sure, is there anybody that could please put a solution foward it would much apprecitated.

 

Many Thanks

 

Kieran O'Brien

[richard]

Do you have two graphic outputs from the macine, or are you running one through the other (which I doubt would work)

 

When I've used Analogue Triple heads on macs before, I haven't needed any drivers, the mac has just recognised the necessary resolution for the THG and it has worked, but I haven't tried more than one at a time.

[kobrien]

Thanks for your reply Richard,

 

yes, I'm running a mac pro os 10.6.1 with 2 graphic outputs, a DVI and a Mini DisplayPort, I have the TH2G-D coming out of one and the DH2G-A coming out of the other.

 

The mac has just 1 graphics card though, it is an ATI Radeon HD 480.

 

We've found that the Mac will recognise the two heads as we can see the extended displays in the display arrangement screen. However, in reality at best we only get the split output from the dualhead and the middle of the 3 tri-head screens outputing to our projectors. On the matrox website it says to check your display resolution settings, and we've done that too.

 

Do you have any ideas? What's bemusing us is the fact that one of our colleagues used 2 tri-heads successfully out of the same mac a few months ago. They were both the same model of Tri-Head though.

 

Thanks.

 

 

 

 

 

 

 

 

Do you have two graphic outputs from the macine, or are you running one through the other (which I doubt would work)

 

When I've used Analogue Triple heads on macs before, I haven't needed any drivers, the mac has just recognised the necessary resolution for the THG and it has worked, but I haven't tried more than one at a time.

[Ian H]

Might be better to post question on www.Catvx.com or http://chaldee1.gotadsl.co.uk/~richardb/up...searchid=215112

 

at least there you might get a response from other cat users.... Nev, Simon or even Richard

 

Ian H

[richard]

A couple of things to check..

 

- If you just use the TH on its own does it work? If so does it work out of both outputs

- You need to ensure that the TH output is at a resolution of something like 3076 x 764 (can't remember the exact settings)

- Try above with the DH, I assume this needs to be at something like 2048 x 764

- If you are using a digital TH are you using the DVI cable that came with the box, I seem to remember that TH's are very particular about their cables, and if you use the wrong one they don't work.

 

Annoyingly I seem to remember trouble-shooting a similar problem with a digital TH a while back, but can't remember what I did to fix it! Sorry!!

[AHYoung]

First thing is to make sure that you are using a dual link dvi cable, the short one that comes with the THTG is, but you may find that the one you are using isnt. Then id suggest you instal matrox Power Desk (I think) from the matrox website. this will allow you to set the various resolutions/ refresh rates that work with the THTG it will require a reboot, but after that it should work. I remember that without installing the software the box would only work at 2400/600 on the MDP port and not at all on the DVI on our machine, but then again I could be remembering wrong....

 

 

there is a status light on the THTG that goes green when it recognised the right signal from the graphics card, if it doesnt, it will generally still output a signal, but not split it , they are fussy and unless it get what it expects, it wont work properly. if you appreciate a challenge you should try and get one working with a linux based system....

[indyld]

Wow, seems to me after a certain amount of research that the Matrox DualHead and TripleHead are becoming quite common as solutions to some performance display requirements. One of the reasons I got one is that I was assured by "proper" vidiots (at CT and also on various No1 tours) that they were indeed a professional, but cheap, fix.

 

OK, to my question. It's more of a technical wondering, rather than a request to solve all my problems. I thought it best to add it to this thread as it sort of links with the OPs issues.

 

At my institution, I have secured a Mac (spec, er, dunno, newish though), and Qlab Pro Bundle License and a Matrox TripleHead VGA edition. We also have a simple USB to 8 x audio outputs, which means we can deal with more outputs than simple stereo if we wish. Lovely.

 

On testing the Matrox, the maximum resolution we could get out of this Mac was 2400 x 600 - OK, but not really the 3 off 1024 x 768 I wanted and was convinced it would do. I got the VGA version because there are still plenty of non digital bits of kit around. We used the thick VGA cable supplied with the Matrox, something that struck me as pretty important, rather than just any old cheapy, thin VGA cable.

 

The weak point, as I see it, is the MiniDP to VGA adaptor. Dunno what it does but I assume it pulls RGB and Sync from somewhere in the MDP and not much else. I'm pretty sure that the problem is not with the graphics capabilities of the Mac but I am willing to be told otherwise.

 

So, we tested the Matrox using a colleagues older MacBook Pro, using it's DVI port and the DVI-VGA cable supplied with the TH. Ooo, 3 x 1024 now. That's great, it's just this is the wrong machine and the show Mac only has MDP.

 

The question is, am I right in thinking that the problem is with the MDP to VGA Adaptor and how can I solve this? I have looked at getting MDP to DVI adaptors but wonder if they aren't just another weak point.

 

What happens down that thick VGA cable other than RGB? The input on the Matrox is the same VGA, so why should the DVI from this old MacBook enable a much more useful resolution?

 

//edit to add: Oh, and I looked at Power Desk, and had a go at installing it but it didn't seem to bring much to the party. In fact, Power Desk for Mac install seems to just add a simple driver and utility. For some reason, Powerdesk seems to support all models of the Matrox, including the Dual Head analogue, but not the VGA Triplehead.

 

What I need is someone who knows a lot more about video than I do........

 

Thanks in advance.

[richard]

I was using a vga triple head with a MDP to VGA adaptor (but interestingly not the matrox VGA cable, just an old one I had around) and got the full on 3 1024 displays, the option just popped up in the displays options when I disabled mirror-ing.

[indyld]

Thanks Richard, at least I know that it's possible.

 

I got in touch with Matrox Tech Support who gave the party line "if your Mac has MiniDP you will not be able to connect the VGA or DVI, you need the DP version". I guess that I could see if it's not too late to swap it out for the DP one and then use adaptors to get VGA Out.

 

Perhaps in the future, others can add their experiences of the Matrox DH and TH to this thread.

[nawvernmonkee]

Perhaps in the future, others can add their experiences of the Matrox DH and TH to this thread.

 

I happen to be using them on a job at the moment. Initially we used the VGA version (TH) to split 1 predesigned presentation across 3 screens.

 

The gfx o/p of the provided laptop was 1920x1200 and therefore the max res we could achieve on each screen was 640x480, it is my understanding at this moment (and please anyone feel free to put me right on any of this) is that the VGA version will simply split whatever is the max capability of your output 3 ways. I needed 1024x768 so therefore I would have needed a gfx o/p of 3072 wide at least.

 

On a subsequent version of the same show we now use the digital version (TH) which the eqpt providers set up successfully prior to the job, direct to 3 projectors. Again it is my understanding that the digital version acts as an external gfx card essentially. You need the powerdesk software to run the box easily. THAT SAID I can only get one of these two identical laptops to work on site, and frankly I can't remember how I managed that. A switcher has been introduced to the system (aw quattro vue) however when going direct to the projectors one of the machines is not picking up one of the screens which unfortunately appears to render the software useless as it seems to be relying on doing so. I have heard that the matrox boxes are fussy when it comes to cable length (tsk!).

 

As yet I have been unable to consult some chaps I know are using it successfully yet but we have the show running, albeit without back up. Hopefully at the end of today I will get time to investigate further but for now it is safe to say that this is extremely frustrating and whilst this rant probably offers no help to anybody, I too would be happy to hear of others experiences with these boxes.

 

All the best

NM

[AHYoung]

the important lesson ive learnt about the matrox product is that it isnt a box that simply splits anything you input 2 or 3 ways. It is exteremly fussy about the signal you send it and basically the graphics card has to be running the right drivers to work. You cant plug it into any machine with a vga and expect it to work. It took us about 3 days to find a set of VESA timings to make a Linix based system to work and id be highly surprised if you can produce the right stuff from the output of a switcher or scaler.

 

Its also niave to expect a analoque Vga splitter to be able to output 3 / vgas as thats just to high for your vga laptop etc. If you need that res, you need a Digital edition triple head which has the advantage of also offering analogue in and out. You then need a dual link Dvi input and a machine thats capable of actually running video that res...

 

from further investigation another issue is the cursed MDP - Dvi adaptor as this just wont work at a high enough res ie single rather than dual link. Apple sell a active MDP - Dvi adaptor for 60 quid odds which should work properly upping the res to 3 / 1024 rather than 3/800.

 

if you need a more stand alone box, there are options...

 

http://www.datapath.co.uk/vqs01.html for the Vqs1 which will work on the lower resolutions from pretty much anything, and higher resolutions if you install the drivers {and the machines up to it}

 

even more stand alone is the Kramer Vp423 . http://www.kramerelectronics.info/products....asp?pid=1711#t. you need 1 for each output and the max total res in Wuxga, but its a workable solution.

[nawvernmonkee]

Yep, understand all that completely. Had to explain to PM that digital version was required for our little job for the res he needed.

 

The main job that this sprang from used a spider system and this was designed as a cost effective alternative satellite event which, to be honest, works a treat for what it's doing.

 

We do in actual fact have one system working without any problems running from 1xlaptop-1xth-3xswitcher-3xscreens all at desired res all lined up and lovely looking. Back up system is just not happy though and won't play (either with itself or with switcher), so we have a show at least.

 

My earlier comments about the software not seeing the screens now seems unfounded as the working system also claims not to see 2 of the 3 screens oddly. So we let the show run and revisit later.

 

Interesting comments re the powered dvi adaptors that is something we will look at if needs be but at this moment I suspect that the drivers may be the first thing we look at, unfortunately that won't happen now till we get back to the unit.

 

As I mentioned earlier there are others using this system effectively so I am sure it wont be anything too frightening upon further investigation, fussy however is a very apt description.

 

All the best

[sleepytom]

id be highly surprised if you can produce the right stuff from the output of a switcher or scaler.

Best sit down then!

 

TVOne Corio2 switchers work upstream of the TH2Go without any overly complex settings. The only limit is their resolution which won't go higher than 3x VGA or 2x XGA.

 

Also worth a look at are the MViewer chinese copy of the th2go - I have one and it has proved to be very reliable and flexible compared to my older matrox analog TH, with higher resolutions supported and it runs a good deal cooler than the matrox which gets really rather warm when running for a few hours.

[AHYoung]

But I am sitting down how, else would I be using a computer... and whilst maybee you can get a THTG to work on the output of a scaler, most have a limit of 2k so you cant get the three outs running at a usefull resolution as even 3 SVGAs takes you to 2400 wide. Fair enough you can get 2048/480 out , but why bother? ok it works, but at a res thats not actually much use for anything.

 

Anyways I stand by my assertion thats whilst once its running the THTG are very good { 3 xga outs from 1 dvi } , but getting there can be more tedious than required and they are not really designed to plug into anything thats not a recent microsoft or apple OS.

[nawvernmonkee]

But I am sitting down how, else would I be using a computer... and whilst maybee you can get a THTG to work on the output of a scaler, most have a limit of 2k so you cant get the three outs running at a usefull resolution as even 3 SVGAs takes you to 2400 wide. Fair enough you can get 2048/480 out , but why bother? ok it works, but at a res thats not actually much use for anything.

 

Anyways I stand by my assertion thats whilst once its running the THTG are very good { 3 xga outs from 1 dvi } , but getting there can be more tedious than required and they are not really designed to plug into anything thats not a recent microsoft or apple OS.

 

+ 1 for that