Petzval or not??

Well, I got that "Petzval fever" one day, and during healing got a nice 6" Magic Lantern lens of E-pay (thank you Ole). Since it had two fungus spots, I opened it to clear it and to see what's in there. Front element is doublet and in the rear there is an air spaced doublet. What stroked me as odd is, that from Jason's avatar and from on-line resources Petzval should be +-:+- construction with not much air between rear elements. Mine lens is +-:-+ construction with something like 5mm gap between rear elements. Can some kind soul shine some light inn, please??

Marko

Your lens is a Petzval-type. The Dallmeyer version (my avatar) version has a reversed rear element.

Thank you Jason. I shall read your messages before opening my big mouth :rolleyes:. It was some on-line pages that confused me. They even list two cemented doublets as Petzval (+-:+- type, not the Aplanat type). So thank you again for clarification.

Marko