Creative COW SIGN IN :: SPONSORS :: ADVERTISING :: ABOUT US :: CONTACT US :: FAQ
Creative COW's LinkedIn GroupCreative COW's Facebook PageCreative COW on TwitterCreative COW's Google+ PageCreative COW on YouTube
FORUMS:listlist (w/ descriptions)archivetagssearchhall of famerecent posts

Altman Q360 spotlight not sharp - what gives?

COW Forums : Lighting Design Pros

<< PREVIOUS   •   VIEW ALL   •   PRINT   •   NEXT >>
Share on Facebook
Shawn MillerAltman Q360 spotlight not sharp - what gives?
by on Apr 3, 2009 at 5:56:02 pm

Hi all,

I just recieved an Altman 360Q spotlight and I can't seem to get it to focus properly. The best I can seem to get is a somewhat soft pattern on a wall 23 feet away using a steel gobo. What puzzles me is that I can get it to focus if I move the lense half an inch further (forward) than it was designed to go. Am I missing something?

Thanks,

Shawn



Return to posts index
Reply   Like  

Dennis SizeRe: Altman Q360 spotlight not sharp - what gives?
by on Apr 4, 2009 at 2:16:31 am

I'm sorry you ended up with a 360Q (How's that "green" beam of light working for you?)
You're using the wrong lens for the distance you're trying to project your gobo at. You will never get a sharp image with an inappropriate focal length lens.
I would guess you have a 4 1/2" x 6 1/2" fixture (maybe even a 6" x 9").
For the distance you're trying to light you need a 6" x 12" lens tube.

Out of curiousity, what is the beam spread diameter on the surface at the distance you're lighting?

DS



Return to posts index
Reply   Like  

Shawn MillerRe: Altman Q360 spotlight not sharp - what gives?
by on Apr 8, 2009 at 11:12:51 pm

Hi Dennis,

Sorry for the delayed response, it's been a busy week.

"How's that "green" beam of light working for you?"

I haven't noticed a shift in color so far... does this model have issues with color?

"I would guess you have a 4 1/2" x 6 1/2" fixture (maybe even a 6" x 9")."

I have a 6x16 lense tube.

"what is the beam spread diameter on the surface at the distance you're lighting?"

About six feet.

Thanks,

Shawn




Return to posts index
Reply   Like  


Dennis SizeRe: Altman Q360 spotlight not sharp - what gives?
by on Apr 9, 2009 at 4:30:59 am

Historically the Altman 360Q -- one of the more "economical" lekos on the market -- has always emitted a beam of light that was slightly "greenish" due to the glass used.

As I said before, you're using the wrong lens. I assumed for such a short distance you erred on the wide angle side. The 6" x 16" lens is made for throw distances of about 40'-0" (also useful at 30 feet if you don't mind the small beam spread), and will never achieve a sharp focus at 20 feet.

As I said, for your distance you need a 6" x 12" lens tube (or even a 6" x 9" if you need a bigger beam spread).

Your best bet if you're never projecting at the same distance is to purchase a zoom leko (ellipsoidal).
ETC makes an excellent 25 degree to 50 degree zoom ellipsoidal which would be ideal for your range. If intensity is not as important, but size and weight is, the Source 4 Junior zoom would be your "best friend".

DS



Return to posts index
Reply   Like  

Shawn MillerRe: Altman Q360 spotlight not sharp - what gives?
by on Apr 10, 2009 at 8:52:59 pm

Cool, thanks Dennis.

Shawn



Return to posts index
Reply   Like  

john sharafRe: Altman Q360 spotlight not sharp - what gives?
by on Apr 8, 2009 at 11:28:28 pm

The lenses in these type of pattern lights are not the highest quality, a;though Source Four has recently added a line of "enhanced definition" lenses as higher prices to solve the issue you describe. Of course you must carefully calculate the trhe distance of the throw, the desired size of the light pattern and then deduce the angle of the lens required.

JS





Return to posts index
Reply   Like  

<< PREVIOUS   •   VIEW ALL   •   PRINT   •   NEXT >>
Share on Facebook


FORUMSTUTORIALSFEATURESVIDEOSPODCASTSEVENTSSERVICESNEWSLETTERNEWSBLOGS

Creative COW LinkedIn Group Creative COW Facebook Page Creative COW on Twitter
© 2014 CreativeCOW.net All rights are reserved. - Privacy Policy

[Top]