Does anyone have any advise on the use of a DL2 to shoot a image on a building 180' away from the Light? I have a client that wants to shoot a logo from the roof of one building to hit a flat wall on a taller building across the way. I was wondering if doubling up the image with two units would help. The building we are shooting at is under construction and dark. Any thoughts would be apreciated.
The DL.2 lens calculator is here: highend.com/products/digital_lighting/dl_1-dl_2_projection_chart.asp
The lens charts for the DL.3 option lenses can be found here: highend.com/support/digital_lighting/dl3.asp
Given the relatively long throw, I suspect you'll want one of the optional long-throw lenses from the DL.3.
To figure out how many units you'll need, you'll need to know what the ambient light is in the area, and how much brighter than that you want to be. You'll also have to take into account any loss due to atmospheric haze.
Keep in mind that DL.2 lens in the Christie projector will not come to full sharp past about 62' (This is the same for the Standard lens in DL.3 as well).
This may not matter as you are projecting onto a building.
Yes, doubling them up will make them brighter.
I think a better option would be DL.3s with Ultra-Long throw lenses. But even the Ultra-Longs are not spec-ed by Christie for more than about 160'.
Just to clarify, as Marty did pretty well already, you can't use a DL.3 long throw lens in a DL2.
Also, you might want to consider using a SHOWGUN to do this. If the image doesn't need to be extremely high resolution and doesn't need all the fancy effects a media server can do, SHOWGUN should work quite well.
