hi gang..

i am 1 week close to testing my "very slow progressing homemade mini35 design (due to my exams at school)"...

i am using a 1.4 pentax slr lens..i must keep a CONSTANT distance between th ground glass and slr lens...which is 45 milimeters in other words 1,7578 inches...i am wondering does this distance change in different brands of lenses??..or lets say i want to use a 35mm lens...?

any one have any idea about this..?and is the length i am talking about called focal length ?

cheers

You are looking at the "flange distance". A table for various stills cameras is here:
http://www.graphics.cornell.edu/~westin/misc/mounts-by-register.html.

yeah valeriu thats what i was looking for...do u have any idea from which point to point do we calculate...is it from the bayonet to the lens where it touches the bayonet?

AFAIK it is measured from the body to the film plane or from where the lens and body make contact.

just what i wanted thanx pal...

this is what I use in the static adapter to get a perfect focus to the ground glass.http://www.thorlabs.com/ProductDetail.cfm?DID=6&ObjectGroup_ID=214&Product_ID=1486

screwed (adjustable) flange distance was what i had in my first design..but when i speeded up the gg i saw vibration and it caused the ground glass to move milimeter by milimeter very slowly...i am now making another design with fixed flange distance...