8mm Forum: Adjusting focus on BRAUN VISACUSTIC

This is topic Adjusting focus on BRAUN VISACUSTIC in forum 8mm Forum at 8mm Forum.

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Posted by Marc Marti (Member # 404) on November 25, 2013, 02:33 PM:

Hello,

I've noticed lately that my Braun Visacustic can't focus through the entire picture. You have to choose the middle or the edges. Also, it varies when a different emulsion is spliced, something that shouldn't happen in these machines.

Anybody knows how to adjust the pressure on the film gate?

Posted by Paul Adsett (Member # 25) on November 25, 2013, 08:21 PM:

Very puzzling that you have this problem with that rear sprung gate.

Posted by Marc Marti (Member # 404) on November 25, 2013, 08:52 PM:

I've tried with two different lenses: the Schneider 1.1 and 1.2.
Same problem...

Posted by Dominique De Bast (Member # 3798) on November 26, 2013, 11:19 AM:

I have also a focus problem with my Bauer T 502. A part of the picture is from time to time out of focus. When I press the pressure gate with the finger, it seems to be ok so it is probably just a question of adjustment. I was hoping to read some solutions for the Braun that could have been applied on other projectors (like mine). Otherwise, I will consider to bring it to someone who can fix projectors (but I do't know anybody in my town).

Posted by Maurizio Di Cintio (Member # 144) on November 26, 2013, 12:48 PM:

Hi, Dominique. The pressure pad on your Bauer is a standard design, so the film gate faces the lamp housing and the pressure assembly faces the lens. Inconsistent, not edge to edge focus on this projector, might depend on a worn-out pressure pad (don't forget it's made of plastic) or it may need registration/adjustment of the force it applys to film. On the Braun this should not happen, unless there is a faulty spring on the pressure shoe (which in this case, faces the lamp housing), or some other issue which I am unable to figure out.

Posted by Dominique De Bast (Member # 3798) on November 26, 2013, 12:53 PM:

Thank you, Maurizio. I understand from your answer that I cannot fix it easily myself. I think it is more a question of pressure as the picture is sharp, then out of focus then sharp again on a part of the picture.

Posted by Marc Marti (Member # 404) on November 28, 2013, 07:23 AM:

Thanks, Maurizio!

I'll check what you say. I remember also that the repairman who adjusted it some months ago, told me that he reduced the pressure on film for getting better projection of new emulsions like Velvia...

Posted by Andrew Woodcock (Member # 3260) on November 30, 2013, 07:35 PM:

On the Bauer Studioklasse machines there are a few watchouts you can do to try to improve the focussing. First check the spring inside the lens housing is both seated correctly and has a small amount of grease on it to keep it flexible this spring is fitted to keep an even amount of pressure on the rear of the lens barrel but can tilt if the above is not observed. Secondly look closely at the pressure plate springs, tiny retaining circlips and very small screws that secure the assembly. Occasionally these screws come loose or missing and if an incorrect one is fitted that is slightly too long then the pressure plate will not align itself correctly against the tension of the springs.

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