I’ve hesitantly come to the conclusion that there is no good answer to the question: which yields the best picture: VGA, DVI, or HDMI. Based on an unscientific google search, it seems to come down to what specific hardware you are using and how good that hardware is at processing the digital/analog data. In some cases VGA looks better than digital and vice versa. And then of course what looks good can be objective.
Right now NewEgg is selling open box Digital DH2Go for the same price as the analog version. So for an extra $30 or so for some adapters a Digital DH2Go would theoretically have all the features of the analog version plus the digital version. I could use DVI to the DH2Go input and then use 2 DVI-to-VGA adapters for analog output.
My projector supports HDMI and VGA and my computer supports VGA, DVI, and HDMI. I have one projector that requires about 100’ of cabling and the other is less than that. I’d like to save some dough on cables and extenders by using VGA instead of HDMI but not at the expense of image quality. Currently I have 2 projectors hooked up via VGA cables and the only problem is that the cheap VGA splitter introduces banding (the splitter would be taken out of the equation with the DH2go).
Theory and practice are two different beasts. In your experience, what combination of DH2go and cabling works best for long runs?
VGA pins are too weak and can be easely destroyed in the rush
same for DVI, with the problem of digital signal and distance troubles, wich coasts a lot of money to repeat.
HDMI: good connectic, but only 8 meters runs. Repeaters are very expensive ( by the hell !!!)
analog multiplexor using RJ45 to transport the signal is the best solution and you can use RJ4 devices easely to make a longer distance at short prices
i m using this product: http://www.kramerfrance.com/products/model.asp?pid=1355 but Kramer’s product are not really recommanded for touring ( roads, vibration etc…), a special care must be taken with the devices ( protected case with foam)
but in terms of distance and replacement of cables, its really the best solution for a long time system, moving from place to place.
CAT5 works ok, but CAT6 cables are more saffer.
I think I haven’t yet bent a VGA pin in my cables, and even if I did, I’ll just bend it back or throw away the cable…
I think I would never consider using HDMI because then I’ll have to deal with fickle HDCP problems.
analog/VGA fails more gracefully than DVI over long distances (pic quality just gets worse for vga, dvi more or less suddenly fails to blue screen)
If you’re considering a digital multihead, confirm beforehand that the graphics card output is dual link dvi (for higher resolutions)!
I would use digital head with adapters and VGA cables downstream, maybe even 5xBNC cables, I’ve seen this setup work properly very often now. If more money is available, DVI over fibreoptic is also a nice option.
I don’t have personal experience with RJ45 adapters, so can’t really say anything about them.
karistouf what brand would you recommend for touring, if not kramer?
dont know. until a new HD project, no idea about it.
actually i prefer to work on less resolution because full heavy shadering work…
with kramer set you have a 500 euros bill for a transmitter and a receiver.there is a german company ( dont remember their name) wihc seems to do good material.
all what i’ve used (CAT ext.; DVI Splitter and Switcher; DVI detective) are HQ
We got a TripleHead2Go Display Port edition, I can tell you it s getting dust on the shelf cause we haven t been able to get the proper equipment featuring the latest video adaptor… ;(
nice advantage to the digital version of the Matrox Xhead2go is power via USB. I’ve seen some ugly power setups when using mutilply Analogue TripleHeads2Gos with loads of 13amp plugs.
The VGA out from a tripleHead is generally weaker than straight from the graphics card. I’ve had problems with this over long VGA runs and rubbish cables. Get the BEST cables and def get some DECENT line amplifiers if you’re going to go over 10m.
I’ve had less issues with the Analogue version than the DVI and yes analogue fails more gracefully.
Only issue I ever have with VGA is the projectors jumping pixel positions when changing resolutions. ie. you’ll map something, come out of full screen, back into full screen and the projector has X shifted something like 10 pixels. Keep repeating out of full screen and back in and then it will line up again or even over time it will jump back. Seen this on more than one model of projector. Digital is pixel absolute so you will never experience this problem.
ive used good quality vga cables which ive connected 25m+25m without an amplifier and had no quality loss, a longer distance i have solved with another two cables of the same length and between them i had a cheap 6o€ splitter which acted as an amplifier and worked perfectly @ high res.
25m+25m without an amplifier and had no quality loss? out of a port on a tripplehead2go?
we use some material for a theatershow that’s very similar to what karistouf uses. 2 x Cat5 for transporting the DVI signal over great distances. It comes with a price, but we shouldn’t really worry until HD is outdated :) And CAT5 in itself is cheap.
Also we use a DualHead2GO DisplayPort edition, but if you can use displayport this similar product from Dell might be worth looking at, it seems quite a bit less expensive
Another advantage of displayport, which might become something to consider in future. ATI’s Eyefinity, which allows you to connect up to 6 displays to one graphics card, only works for 2 ‘legacy’ screens (DVI/HDMI). Going displayport could make things such as dualheads obsolete in a few years. I guess other vendors will come up with similar functionality.
@gilbi, these are the badboys I use and don’t cost tooooo much. They are amazing. The key part being level and EQ controls.
hi ft, i m also in theatre and dance field.
on wich production are you and in wich country ?
are you the one who is working on magy and illusions ?
about vga: not using triple head, but about VGA connection, with proper cables ( steel particles in the shield) I never experienced troubles about signal, no amplifier needed.
be aware that if you are touring, you may experience troubles with the power . always take sound power to put your system ( computer / videoprojector / any accessory in the image transportation process ) or use a UPS to filter electricity.
this is needed also with kramer system and DVI( since i m now with a ups, no more troubles)
I knew that, already checked your website, and quite liked the things you were doing. We are working on some similar ideas. But I am definitely not the one working on magy and illusions, don’t even know what that is, if you have some link where I can check out what these are, I’d be interested…
Anyway, I am from Belgium, and I discovered vvvv about a year ago. I was experimenting with VisualJockey first, because my idea was to create a high level of interaction between video and actors (everything triggered by ourselves - musicians and actors - by using midi).
The idea was to be able to project on many different places on screen, and to get away from the typical ‘here is the projection screen’ usage of video in theater. Besides, I didn’t want to use real video, but animation in order to have more ‘magic’.
We also needed to be able to travel, so to adapt easily to different stage sizes, which is why I created something that has a number of ‘preset areas’ that I can set up once before the show (move, zoom, rotate and perspective correction), and then I can use my preprogrammed scenes, saying ‘play video x on area 1 and video y on area 6’ for instance.
I found out I could only get the speed I needed using the graphics hardware (and something heavier than a laptop ;), so that’s why I moved away from VJo to vvvv. But it took me a LOT of work. (But I managed to get everything working the day of the show, despite 1 unlucky crash which I only managed to solve the week after the first show.)
The play we use it in is called ‘Zwanenzang’ (about Ludwig II of Bavaria), and you can see our VERY FIRST and quite ugly experiments on http://blip.tv/file/3367970/ or on www.eilandverkaveling.be. In the final version, we used projection from behind on special plexi, so it looks completely different now, but we don’t have any useable footage from the final show yet.
Hi ft, thanks for your presentation. so you are not this one, but you are another one ;-)
thanks for the link, tell us when you will have a more new trailer. the smell of the theatre piece appears but not enough to have a complete idea. :-( would like to see more ;-)
yes, definitively IT IS a lot of work. BUT you will do things that nothing else can give to you than a very personnal developed solution.
actually VVVV is moving my work to create more dedicated real time Tools, with a special artistic nature and taste . usually i m more working on fixed things ( heavy editing in video).
actually more and more i m designing patches for the interraction part they will give to stage, and for the life that will happen between actors / dancers and the video technician.
so there is heavy choice of images, shaders, and patch approach, and a big space letted to the “performance” aspect
VVVV changed completely my approach …
but it s really painfull when bug occurs… a mix between light and darkness, depending of the success of a clean patch.
actually to avoid buggy patch and avoid killing ressources with GUI rendering, i m throwing out everything related to GUI. i m now only using whitecat and artnet to remote VVVV. and less and less bugs…
i m now completely laptop oriented, Gamers laptop are ,not too much expensive now.