Configuring multiple screens

[DJ Higgumz]

OK, I have never done this, but I am looking at getting a triplehead adapter to run 3 projectors, however, I want to make sure it will do what I want. I have 2 screens in front on the ground, and one in the back that will be raised about 4 feet. they might have overlap, as shown, but the one on top would be behind the two on the ground. Is it possible to map it like this? I know the computer sees the triplehead as one monitor, so I'm not sure how I could do this, because the projectors aren't just a horizontal span, they are placed at different points of the image. I want to know if this is possible before I throw money down

[pfelberg]

Yes, you can do that and you don´t even need a tripple head for it.

With the usage of a tripple head.
Let´s say you will have a composition of 2400x600 (that is 3x 800x600). The tripple head will consider the first horizontal 800 pixels for the first display projector, from 800 to 1600 to the second, from 1600 to 2400 to the third, no matter if projectors are not aligned in a linear way. You can ovelay them.

Important note:
According to your layout you will need to mask all three videos, so their projections do not overlap. Your mask can be applied on the layer or on each video itself (I'd rather mask all videos). You can also mask out videos on Advanced Output, applying masks.


Not using a tripple head.
It is all about resolution. But you can use a single projector and still achieve this.
You can have one single video, already masked with all three images on their positions and just map them on the surfaces.

Important note:
Whatch out for focus! The video on the back connot be that too far that will not allow you to focus them all at the same time.

I hope this helps.

[DJ Higgumz]

could you be a bit more detailed please? any tutorials or other threads to help? I want to have it where one video spans across all of the projectors like the picture shows.

[Joris]

Yes, this is possible.

The most important thing to remember is that with the Advanced Output of Arena, the composition is no longer directly linked to your output.

So in this case, your output (TripleHead) would be a 2400x600 image, distributed over 3 projectors.

However, the input (Composition) can be 2 projectors wide and 2 projectors high. That makes 1600x1200. You're only using three projectors, but since the top is in the middle, you need to use a 2x2 grid.

Using the Advanced Output, you can then assign which parts of your Composition go to which parts of your TripleHead.

You need to create 3 slices.

The Input Selection of the first slice (Top) needs to be 800x600 and take its input from slightly under the top half of the Composition. This is to account for any overlap you might have. In the Output Transformation, make the slice 800x600 as well, and place it on the left side of the Trips output.

The Input Selection of the other two slices need to be 800x600 as well, and take their input from the bottom left and right of the Composition. In the Output Transformation they're 800x600, but placed in the middle and right of the Trips.

At the location, you can adjust the shift needed for the top projector by eye. If need be, you can shift the Left an Right slices up instead of shifting the Top slice down, or find a happy medium.

Also, if your Trips is connected differently (ie the top projector is on the third output), you can simply move the slices around in the Output Transformation. What you're actually sending to the Trips is arbitrary.

It's a bit of a stretch to work your head around, but once you're able to make this switch, the possibilities are endless.

[DJ Higgumz]

Awesome thank you! for my composition, does it have to be the resolution of the sum of the projectors? or can I keep it at what I have it at 1024x728? I want to save as much cpu usage as I reasonably can without loosing noticeable picture quality

[Joris]

Using this method, the composition size is independent of what you send to the projectors. There is nothing stopping you from making it 1024x768 or even smaller (or bigger for that matter).

You might want to check if this does not result in too much resolution loss though, as you will be stretching things from 512x384 to 800x600 (or whatever the Trips and projectors can handle), which is almost four times as big.

[Joris]

BTW, looking at this again, you probably need to do some masking on the top slice, but that's as easy as adding a mask and blacking out the bottom part of the top projector.

[DJ Higgumz]

I'm intending to keep it overlapping the slices, my thoughts are to give some definition to the screen setup? it is for mobile DJ, so there will be viewing from the sides and what not. the rear screen will be at least 5 feet back or more from the two in front. I will probably need to adjust the size of the rear screen trim when I get all the equipment setup.

[DJ Higgumz]

and they are all rear projected with short throw lenses