Subject: Formula to calculate the final resolution (in line pairs/mm) on photos

An image has to go through the lens to the film. To be enlarged it has to 
go through the film and the enlarger lens and is projected on the paper.
At each stage we find different resolving powers. E.g.: The taking lens 
might be capable of 90 lp/mm, the film of 160 lp/mm, the enlarger lens of 
80 lp/mm, etc.) The final resolution would depend on all these factors 
plus the degree of enlargement. I wish to relate this final resolution to 
a visual acuity of one minute of arc.

Re: Formula to calculate the final resolution (in line pairs/mm) on photos