Colortran Ellipsoidals & Gobos

[zackw250]

Has anyone used any Colortran 5/50 Ellipsoidals with steel gobos? If so, how was the projected image? Was it crisp when you wanted it to be? Did you have to purchase any special adapter for the gobo?

[Les]

I have never used the Colortran but I think the optics should be close to a 360Q, which I have used. The projected image was o.k. It was clear, but the contrast wasn't as good (between projection and surface) as you would get from a higher performance instrument. Still acceptable though. The really intricate ones tend to not look as good as simple things like breakups. I doubt you will need a special adapter as long as you have the correct gobo holder. Again, I think an Altman 360Q holder would work but I'm really not sure. Since the Colortran's have aluminum reflectors, the gate area really gets hot, so don't be surprised if your gobos get some pretty bad warps, or even burn-throughs by the end of their run. Make sure your lamp is centered and aligned correctly too, this will effect the amount of heat in the beam and the amount of halation on the projection.

[DJErik07]

There are things called donut, that are made to help focus the image from the gobo. i have never used one before. I usually use 360Q's and don't have any major problems.
Here is the link if you want to look at the donut (it is a PDF):
http://altmanlighting.com/Data/Detai...onuts/8-DN.pdf

[SuperCow]

Whenever I'm using a gobo that is likely to be scrutinized, I use a donut and a snoot.

[zackw250]

Why?

[SuperCow]

To avoid spill light at all, ao that the gobo is very clear.

[zac850]

When would one use a donut vs. a normal gobo holder? When ever I have used gobos in my source 4's or designed with gobo's, I have always just put it in the gobo slot. Why would someone opt to put it in a donut?

[DJErik07]

The donut goes in the gel frame holder (I think) and you would still use a gobo holder for the Source 4's

[avkid]

I have found that Colortran Ellisoidals will not accept "universal" gobo holders. I believe a donut sharpens and focuses(make it smaller) the image a gobo projects.

[Les]

Yes, donuts slip into the gel frame and sharpen the image by cutting off the stray beams of light. The donut for a source four or SL / Shakespeare would have about a 2" aperture. If you order a donut for a colortran, be sure to specify a 7.5". The most widely used donuts are about 6.5" square which are designed for higher-end ellipsoidals.