have you ever seen one of those clamps that are used
to hold gobos infront of lights, or reflective / black/white &c cards
over. below to the side &c of lights ?
they are clamps on both sides and an adjustable snake/arm in between ...
can you just get a safelight filter, from an old bullet or square safelight
and just clamp one side to the filter,and the other to your enlarger body ?
you won't need to cut or trim or anything, ... and it would be adjustable ...
and probably would cost only a few dollars ..
Thanks John. I've the mechanism (below) just (just being the operative word), need some glass as specified in post 1, that I can insert into:
Wanted solution, a red glass as specified in post #1 to replace the yellow you all see in post 1 and in the first pic of this post:
I think I should be able to solve this little riddle with a beat up used 25a and a glass cutter but
I've no idea??
This could possibly work for you. I have made some graduated filters from Cokin or Lee clear (I believe) polycarbonate square filters by dyeing them in RIT fabric dyes. The dye solution was very hot and they did not warp. They can be cut to size but I don't know about the color wave length. The optical properties if that is an issue are very good. But I think they are more than 1mm thick. Also check Anchor Optic division of Edmonds Optics.
^Dying glass in RIT? That's te kind of MaxGyver I'm talking about! Hummm....maybe take a cheap-old-skylight/uv-filter boil it in red RIT have it cut to my 17x20mm spec???? Hmmm food for thought
Is a skylight filter permeable?
Cut down a piece of rubylith and sandwich it between two bits of microscope slide, or even just stick it on one piece. The camera filters you mentioned will be even less safe than the 'proper' red filter.
It would actually be simpler just to make an under-lens swing filter using rubylith, a piece of plastic or plywood as a frame and a few cm of alloy strip as a support, attached somewhere convenient near the lens-stage.
Would a glass slide mount with a piece of rubylith inserted solve your problem?
I worry about staring a fire. I put a meat thermometer into my enlarger head and it got to 200F. A Roscolux #19 can get to 220....I think it has to be glass to make me sleep at night and not catch flame if I ever turn my back????
The part seen in the photo above, from the OP, is from a Leitz Focomat V35 enlarger isn't it? I'm not going to dismantle mine now to check, but I think I recall that the dichroic filters are after the heat-filter in the light path and not in the hottest part of the head.
However, removing one of the filters being used for the variable-contrast filtration will mean that you need under-lens filters to use VC paper anyway -- so wouldn't that be the easiest place to put the red filter? (Plus you get one in the under-lens set anyway, so don't have to make anything except a simple bracket to support the filter-holder).
Yep it's a V35. I use graded paper and the MG head above actually has one of the two Dicro filters missing (I got it that way). So it is useless even for MG paper and I thought I'd mod it to hold a photo-paper-safe red filter.
I put a thermometer right where the light hits the Dicro head glass filter and it got to 200F. A Roscolux can get to 220F and that's cutting it close for comfort.
Seems the most safe route is the Edmund glass filter cut to size ($40ish) or buy a b/w only head ($100), like this Leitz part:
Or a under lens filter, which I have but just don't really like the ergonomics:
Really not too much of a bother just want to put that broken part to work...
I was going to suggest this. Or if you have a 6x6 glass slide mount, take the glasses from that.
Originally Posted by MartinP