Masking in the darkroom

[miissaka]

How many here uses masking in the darkroom? I gave it a try after reading the articles in "Way Beyond Monochrome" (for example, this: http://www.darkroomagic.com/Publications/WBM/UnsharpMasking.pdf ) It is not a technique for all negatives, that's for sure. I tried using tape and a light table but for me it is tedious at best. However, the results were promising so I begun to look for more usable alternatives.

I searched the net for prices on masking kits and carriers and quite quickly decided that I'd first try to build my own. 🙂 I'm using a Beseler 45 MCX for my large format and 35mm negatives. I already have read the article by Mark Jilg and Dennis McNutt (http://web.archive.org/web/20020603051329/hps.vanguard.edu/Photo/Art1Sidebar.html - it is no longer available at the original site)

So, here's my plan roughly:

I plan to use MDF as the base material since I can work with it rather easily and it is stable. (I made a prototype negative carrier from it and I must say it has to be finished with paint and whatever in order to keep it from producing dust!) My plan is to rout tight recesses for the bottom glass, film and top glass. Then I'll install punch/registration pins to the carrier so it'll do double duty as a punch as well. I'll do a Sketchup drawing and post it here so it'll be more easy to understand.

Should I take the pins/punches from an ordinary paper punch or can I device them from somewhere else?

Any suggestions or advice is appreciated.

Mikko

 

[miissaka]

Carrier plan

Carrier plan

After posting the previous message I begun to think that making dedicated carriers for 35mm and sheet films might be the way to go. So, here is the carrier for 35mm film. It is also be used to expose the masking film - I just place a piece of black paper on top of the bottom glass.

I "zoomed" into the essential parts instead of the overall view. After all, it is just a 300x210mm rectangle. 210mm is the diameter of the original Beseler film carrier. The 300mm length is to offer more support for the film strip and protect it while it is in the enlarger.

The idea is to rout a full length 35mm wide recess for a film strip. It should be a snug fit since it should limit lateral film movement. The depth of the recess is 2-3mm. Then I make a 4mm deep recess for the top and bottom glasses, both of which are 80x55mm or so. After that I rout the opening through the carrier, 80x25mm. To limit longitudinal movement I place two pins in the 35mm groove to match the perforation holes in the film. A piece of broken 2mm drill bit gives a very tight fit.

Why 80mm long? Well, if I offset the carrier 20mm, the other half of the opening is in the center. If, and when I one day find that I've scratched either of the glasses I can use the other half. Also, I trust that the weight of the glass is enough to keep the film flat so the top glass needs to have more size than little over a 35mm frame. And you never know if I one day find a good deal on a 35mm panoramic camera.... 😉

This design should be simple enough to construct and I do not need to implement hinges for the topmost glass. The recess should keep it in place when installing or removing the carrier from the enlarger. I think can use 35mm ortho film as masking material because I trust I can make the recess tight enough.

What I have not yet thought out is the way to register the carrier in the enlarger. Preferably this should be accurate and repeatable if I wish to try out masking techniques that require changing the mask.

Comments are more than welcome.

Mikko