Conventional Fixtures Bench Focusing Tips

[cbernier01]

Hey there. It's been about 20 years since I've done any amount of bench focusing and I'm having a bear of a time remembering everything.

Can anyone point me to some good articles on it, and or pass along some good tips before I go cross eyed staring at my white wall with a beam of light.. (I've heard things like removing the lenses... putting a pc of R85 in front...etc..etc..blah..blah..)

Any help would be greatly appreciated!

Thanks

Chris

 

[Van]

Use that there search function, partner. There are EXTENSIVE posts on the subject of bench focusing almost every fixture known to man here on CB.
P.S. Removing the optics from the barrel kinda defeats the purpose and and makes it impossible to bench focus an instrument. Not to mention it makes the front of the instrument extremely hot.

 

[cbernier01]

I shall search. Just hoping that folks would read this and have some tips before I go wading thru tons of posts.
As for removing the lens train... No idea where I read that. Just something I saw somewhere that seemed odd.

 

[sem6727]

If you are bench focusing something like a source 4 I have found that the black wrap method is very useful. This is done by putting a piece of black wrap in a gel frame then making a pin hole in the dead center of the black wrap. This will produce a a reflection of the inside of the unit on the wall. Looks like a bunch of circles. Bench focus until the lines are as sharp as you can get them or the black is the darkest you can get it.

Hope that helps.

 

[Les]

Notice how the term Bench Focus is highlighted in yellow throughout this thread. Click that link and you will be directly linked to instructions on how to bench focus the two most popular instruments in the world - the ETC Source Four and the Altman 360Q. Yay, no wading!

 

[derekleffew]

...I have found that the black wrap method is very useful. This is done by putting a piece of black wrap in a gel frame then making a pin hole in the dead center of the black wrap. This will produce a a reflection of the inside of the unit on the wall. Looks like a bunch of circles. Bench focus until the lines are as sharp as you can get them or the black is the darkest you can get it. ...

A radical approach, but the science behind it is sound--pin hole cameras were the first invented. I'll have to give this method a try. Thanks, sem6727.

cbernier01, as the process is slightly different for each fixture type and model, put "bench focus, <fixture model>http://www.controlbooth.com/forums/members/cbernier01.html" into the search box. If you don't find enough, feel free to come back to this to ask additional questions. Had you not asked, sem6727 would likely not have posted his method.