Conventional Fixtures 50 degree roundels vs. smooth roundels

[regaskz]

Hello!

I help with lighting at my high school. We have 4 Altman R-40s (3 circuit) that we use as a ground row cyc lights to hit the back wall, which is painted white. We have been using red, green, and blue gel to create the three color wash but I think it would be advantageous to switch to roundels. This way there is less maintenance, and the colors would be more exact, from what I understand.

What I am wondering is if smooth roundels or 50 degree roundels would be better for our space. The cycs sit about 1' away from the bottom of the cyc and are angled at (if the floor = 0 degrees) 95 degrees. The wall is 20' high and we realistically only need to hit 18' of it because of the curtain.

We also have 6 Altman Spectra CYC 100s that hang about 8' from the back wall at around 19'.

Also, we are using GE 21213 in the R-40s. Is that the best?

Thanks in advance!

 

[Les]

I think you would want to go with the 50° spread (lenticular-lined), with the lines oriented horizontally, which would spread the light more on a vertical axis. For a cheaper solution, try R104 Tough Silk, which works roughly the same way. Stippled roundels (and other diffusion media) are also available.

FYI, the frames for these roundels can be inverted to tightly sandwich a gel if you'd prefer to go that route.

http://www.controlbooth.com/wiki/?title=roundel

 

[regaskz]

Les,

The R104 looks like a lenticular diffusion without color. Is that correct? If so, would I combine the diffusion with a regular gel?



Thanks!

 

[Les]

Yes, that is correct. The gel and diffusion can be placed side-by-side. Sometimes the color can bleed in to the diffusion, but you can place the color on the far side of the lamp if you wish. Not that it causes problems either way. It's only annoying if you plan on reusing the diffusion for something else, but that sounds unlikely in this case.

 

[icewolf08]

I would second using gel and frost. Roundels are expensive and getting hard to find. Gel is comparatively cheap, so if you ever decide you want different colors, it is simple and inexpensive to change.

 

[regaskz]

The R-40s only have one gel slot, correct?

How would I put both the diffusion and gel color in at the same time?

 

[Les]

The R-40s only have one gel slot, correct?

How would I put both the diffusion and gel color in at the same time?

You sandwich them together.

 

[derekleffew]

To me, really hard to justify spending 48 x $26/ea. = $1,248.00; when an $8 sheet of color yields 12 cuts @ $0.67/ea. Yes, the color needs to be replaced occasionally. The ROI on rondels just isn't there. Save the money for LED striplights eventually.
"...and the colors would be more exact, from what I understand." Not sure what this means. R120, 121, 122; or R124, 125, 126 are pretty exact, too.
"What I am wondering is if smooth roundels or 50 degree roundels would be better for our space." I would say the choice is between 50° spread (lenticular) and light stipple. Clear rondels are used with R40/SP lamps when you want to throw a long distance without diffusion. In your application, you want to do all you can to minimize scalloping.
"Also, we are using GE 21213 in the R-40s. Is that the best?" Yes, the 300R40/FL is the best lamp for these units in your application.

 

[icewolf08]

The R-40s only have one gel slot, correct?

How would I put both the diffusion and gel color in at the same time?

Put them in the same frame. Same way you put color and frost in any fixture.