just remember, your output will have the proportions of a video format ( or multiples thereof if you use a matrox), say 16:9 while your screen is 40:9
you can fix this quite easily in the advanced output if you have Arena.

this kind of problem is too difficult for beginners as you'll need to color match 3 projectors and do the blends
if you dont mind it looking awful, have a go, but if it needs to look ok, find someone experienced to help you.

I haven't tested it, but I imagine the quick fix is to play anything judder crucial in another app and bring it in via syphon.

Tips or suggestions for a better understanding of this process is very welcome. Thank you! i just did a weeks worth of this. you need a light meter to do it properly, but they are hard to come by. otherwise you have to spend an hour or two on each projector balancing the uniformity, RGB global valu...

decent projectors helps a lot.
DLPs made for blending.

with the top end made for planetarium software, its really difficult to do a dome line up. blending it beforehand is totally unrealistic given the wide angle lenses used. - a couple of mm out on the projector position means you wont get your line up. you could use blendy if it ever comes out but eve...

you've used pin registered mounts

use add and turn the V up to 100

just turn the v slider all the way up

I had a similar problem with DVI over Cat5.
the matrox doesn't output power over the outputs, so self powered DVI extenders wouldn't work.