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Paper on the History of Petzval's Lens Design
A friend of mine, Professor Jose Sasian of the College of Optical Sciences at the University of Arizona, recently sent me a copy of his paper on the designing of the Petzval Portrait Lens by Joseph Petzval. He graciously gave permission for me to post it here. Enjoy!
Re: Paper on the History of Petzval's Lens Design
Paper on the History of Petzval's Lens Design
Dr. Sasian was my professor for lens design and aberration coursework when I took refresher courses 10 years ago. He is very knowledgeable on the subject of lens design, both modern as well as the history, and well respected in the optical design community.
Re: Paper on the History of Petzval's Lens Design
Thank you. I’m printing it so it’s easier to read and file!
Re: Paper on the History of Petzval's Lens Design
I have only done a quick read. In spite of the obvious preparative caculations, it is apparent that the practical work with Voigtlander did contribute a lot.
It is suggested that the "tweeking" of the performance - and especialy the maximisation of the flat field - can be done by changing the air distances. This applies to the cell/cell distance and the air gap between the rear crown and flint lenses.
This matches exactly what I have experienced with mounting orphan Petzval lens cell in a new barrel and replacing a lost rear cell spacer. The paper gives both data about how to calculate the distance between cells and between the lenses in the rear cell. Which makes it possible to marry orphaned cells from different (but fairly similar!) Petzvals with a reasonable result, I think?
Re: Paper on the History of Petzval's Lens Design
It definitely takes a few times to go through. It's simultaneously a history and an analysis of the optical science. My poor little brain can only concentrate on one at a time...
There were definitely some freedoms in the Petzval design to be tweaked, and as you would expect, the design evolved significantly in the following years.
Re: Paper on the History of Petzval's Lens Design
Relevant material and good read !
Thanks for posting Mark.
Re: Paper on the History of Petzval's Lens Design
Paper on the History of Petzval's Lens Design
By the way, in lens design circles, the Petzval forms the basis for a large and widely used family of small, very fast, narrow field of view objective designs.. in visible and infrared imaging systems. You wouldn't immediately recognize modern Petzvals as related to the original, but the way they work is all derived from the original.
Re: Paper on the History of Petzval's Lens Design