1. ## Re: Enlarger sizing

Originally Posted by John Layton
Peter...you mentioned birch plywood, square bellows, and rails on wheels... ...Hope this helps...and good luck!
Thanks John. What a great setup! You have the luxury of space. I'll be constrained to running (and projecting) along a 2 ft deep piece of worktop (to a corner wall to the right) but should still be able to get a decent size print.

2. ## Re: Enlarger sizing

Originally Posted by peter brooks
Thanks Len, yes that calculation would be really useful - if possible, could you post it here?
Peter,

It is simply the magnification equation...

Enlarger Negative Stage, Lens & Baseboard Distances => u=v*F/(v-F)=F*(M+1)/M or v=u*F/(u+F)
where,
u = lens to negative distance (inches)
v = lens to baseboard distance (inches)
M = Magnification
F = lens focal length (mm)
u+v = negative to baseboard distance (inches)

I have a spreadsheet where I put that into a single sheet, and ran some numbers for different focal length lenses to determine magnification, given that my enlarger head was hitting the bottom of a floor joist and constraining the maximum u+v value even with the drop table.

Good luck with it,

Len

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