Can't focus a gobo

Joined
Feb 28, 2007
Does anyone know what I'm doing wrong? I have placed a gobo into an elipsoid but can not get the image to focus on an upstage white wall. I have played with all 4 shutters, but only a blurry blob is visible. Is there also a way to focus the lens? Thanks for any help you can give me!
 

Van

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Hmm hope I'm not stating the obvious but did you loosen the focus knob on the barrel of the instrument and run the lens tube in and out ? I'm really not being an ass, I'm assuming from your question that you are not real expirienced with lighting fixtures? Also is your gobo in the gobo slot? or is it in a gel frame slot?
What type of fixture are you using ?
 
Joined
Feb 28, 2007
Ahhhh that's what I need....a focus knob! Where do I find it! And yes, I haven't done lights in years and a different theatre. I'm not sure what type of ellipsoidal it is, but the gobo is in the slot and not the gel frame. A high school kid came in but didn't want to give us much time. I know we've done it in the past but he could only use another light and put it on a side wall...sorry I don't know more, but I'm trying to direct and do lights with a new jr. high person! Thanks if you have ANY suggestions!
 

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Towards the end of the instrument (towards the gel frame) there should be a knob, its either on the top or the bottom, loosend it a bit. That will allow the barrel to run out. To run the barrel in/out grab the slot where the gel frame goes in and pull, and depending on how old the fixture is, you might REALLY have to pull/hit/yell obscenity's. That will allot you to pull the gobo in focus. A donut will also help get the halo out.... they look like this... http://internetapollo.com/Products/Search.aspx?t=donut
 
Joined
Feb 28, 2007
Thanks! I will try that! If I can't position it high enough on the wall without hitting the teaser (small curtain on top of stage?) is there anything else I can do with focusing? Really appreciate the help!
 

Van

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Well on almost any ERS you will find the focus knob on the bottomof the fixture.
If the fixture is hanging with the yoke and c-clamp up and the fixture is right side up < usually with the gel frame holder oriented so the frame wont fall out and the gobo slot up so as the gobo holder wont fall out> the focus knob is usually a three sided or knurled plastic knob towards the front < lens end> of the fixture. Just loosen it a turn, do not remove it all the way. The lens tube should then slide freely in and out without falling out of the fixture. You'll notice an immediate difference in the light output and as you move the barrel in and out you see the image of the gobo come in and out of focus.
As a side note, depending on the fixture you may not want to run it at 100%. Depending on the type of gobo and how much open space it has in it you can burn through it relativly quickly. If, for instance you are running an old er fixture with a 1000 wat FEL you could burn out the gobo vry fast, specially if it is out of bench focus < if the lamp is not properly aligned in the reflector>

Good luck, Hope that helps.

EDIT- if you are hitting the teaser use the shutters to cut off that part of the light. Again try to not cut off half of the light with one shutter as this can have a negative impact on the quality of the focus and if run extremely hot it will lead to premature degradation of the shutter.
 
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Joined
Feb 28, 2007
Wow...thanks! This should help me tackle it again tomorrow. I wish it were on a C clamp, but rather it is on a rivet so I have little control with the distance it hangs. But you have given me good detail to look for. And thanks also for the reminder to not run full, it is an older theatre.
 
Joined
Feb 28, 2007
I have my gobo on the wall I wanted! It wouldn't focus real sharp, but its better than off the stage on a brick wall! Thanks again for all your help! I've got to get back up in those cat walks more...I find I've missed it! Opening night tomorrow.
 

Van

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Yay ! Another Production saved thanks to Control Booth . Com !
 

gafftaper

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Hey DirectorofChildren, let us know where you are at. There are a lot of young folks around here who are just itching to find places to do tech. There are also a lot of older folks around here who I'm sure would be willing to be your local tech guru buddy. Maybe we can find you a friend to help out.


As for the T-shirts I'm in!!!
 

DarSax

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Yeah seriously, if someone made T-Shirts, I'd buy one. Maybe not the weird rediculous quote or whatever, but w/e, I'd show some CB pride.
 
Joined
Feb 28, 2007
I'm working for our pulic school district in Wisconsin Rapids, WI...my training came from Community Theatre and I would eagerly welcome any young person working backstage! We're trying to teach but I love learning right along with them! And T-shirts huh? Well I for one am very thankful to have found all of you here willing to share your knowledge! Thanks again!