Old Brass Lens [mfg] unknowen

[seawolf66]

Well this lens turns out to be A 10.5 inch lens has F-stops of F-8 to F-64 on it , There is no other hint of who made it or anything else; This is the lens I mistook for a focus point of 2.5 inches and ended up being wrong : but did some learning in the mean time,
will take it out for a spin shortlly : and post the results for you folks!to all I say thanks you: Lauren

[Jim Galli]

Well heck, for future ref, if you've got a good aperture scale like on this lens, set it to f10, measure the hole and add a zero.

[seawolf66]

Jim Galli: Now that is simple to figure out : Thanks Lauren

[Glenn Thoreson]

Looks like a classic Rectilinear or Aplanat. Are the f/stops in modern progression? Pretty lens!

[seawolf66]

Glenn: all the F-stops are normal except there is a F-44 than a F-45 thats the only difference : Will look up the glass confirguration in the vada Mercum and see what type of lens it might be : all I know its two up front and two out back ,but the back lens is wider than the front lens ?

[Ole Tjugen]

Wide Angle Rectilinear, then...

Not German; the Weitwinkel-Aplanat have (mostly) two equal-sized very thick cells. The unequal sizes indicate a Rectilinear to me. The aperture scale as well - a more common progression in Germany was 16-23-32-45, or 12-18-25-36-50. Not 16-22-32-44!

[seawolf66]

Ole: I stand corrected, when you look at the lens as a unit it does look like the rear element protrudes father than the front element , but upon removing both elements and setting them side by side their the same height ? Did take it out today and we shall see what it does at F-64 ! thank you your info and help Ole: