Hello again. I've been playing with my camera and I think I'm in love.

I recently purchased a Nikkor-O 50mm 2.8. Has a fungus spot inside but does not seem to affect any images. So I am happy with it, considering I bought it for 15 dollars only.

I have been thinking about other lenses on my Bronica. Tried enlarging lenses, my Rodagon 80mm and my Componon 105mm. I placed them in front of the helicoid on the enlarger's lensboard. I haven't actually shot any picture on film, as I feared that my hand would not be stable to hold the lens.
Member Trask mentioned an adapter to M42, but it's quite expensive. So I came up with an idea. Could it be possible to use multiple step-up and step-down ring filters to get to M42 or even M39. The total cost of a series of these rings would be about 6-7 dollars, significantly less that one adapter. But the main question is one. Will the filter rings screw on the M57 mount of the helicoid? That means, is it possible for a 42mm filter to fit on a M42 mount? (or equally a 39mm to M39) Any member that has a M42 camera-lens or M39 camera-lens with 42mm and 39mm filter can try it and write here if it is possible.

Also, I though that if such a "modification" is possible, then why not, a large format lens to be used. Combining it the the leaf shutter of those lenses, it would be a very interesting experiment. What would be your thoughts on that?

p.s. Do you have any idea judging if the fungus inside my Nikkor is affecting image quality? I mean in regular shooting conditions I can not tell that there is a spot of fungus. But is that enough?