Working F/# ( W.F/#)
Working F defines the brightness of lens at a finite distance.
W.F/#=(1+Opt. Mag)FNO *Relationship between W. F/# and F/#
W.F/#=1/(2NA÷Opt.M)

Working F defines the brightness of lens at a finite distance.
W.F/#=(1+Opt. Mag)FNO *Relationship between W. F/# and F/#
W.F/#=1/(2NA÷Opt.M)