Huck Finn
Well-known
I'm interested in finding out what formula was used to design the 40/1.7 lens on my Canonet QL17. Does anyon have any idea? Or what source might provide such info? Or even a lens diagram? I've had no luck searching for any of this.
Thanks for the help!
Huck
Thanks for the help!
Huck
back alley
IMAGES
40mm f/1.7 (6 elements in 4 groups)
that's it from the canon museum.
that's it from the canon museum.
Hmmm... Sounds like a classic double-Gauss?
Pherdinand
the snow must go on
Well. The front element is a single positive convex-concave.
The central element is a cemented doublet.
That's all i know
The central element is a cemented doublet.
That's all i know
Huck Finn
Well-known
Doug said:
Yes, Doug, that's what I found when I continued my research. I still haven't found a drawing, but I did find a reference, which indicates a classic double Gauss, which was the primary suspect all along. Pretty much what Pherd describes, which a mirror image on the other side of the shutter, I suspect.
Thanks, guys.
Canon Junkie
Established
http://www.kyphoto.com/classics/repairmanuals.html
go there and get the schematics for the camera and lens... will give you the whole design
go there and get the schematics for the camera and lens... will give you the whole design
Huck Finn
Well-known
Junkie, I can't tell much about the lens elements from that. I downloaded the repair manual, but too small & sketchy to tell much. Am I missing something. It is a great resource for other purposes, however. Thanks for the link!