Didn't Wisner try this - and give up?Originally Posted by Terence
The inside curvature is too deep for automatic grinding, I think. So maybe the Chinese could do it by hand
I just got hold of Rudolf Kingslake's "A History of the Photographic Lens", an interesting read for anyone into this sort of stuff. If you want to avoid cementing lenses (or antireflex-coating them), the Steinheil Periskop and Zentmayer hemisymmetrical would be the easiest to get anywhere near decent results from. After those a Cooke Triplet, perhaps?