Differences in petzval makers - Significant?

[goamules]

I've been directed to that site for a couple years, and just now figured out the navigation. There is a wellspring of quantitative data there, even on several Voigtlander and I think one Dallmeyer Petzval. The problem is it's difficult enough scientific data already, and it's in French also! I couldn't find the projection section, but here are some petzvals:
http://dioptrique.info/base/n/n_portrait.HTM

Task for someone:
1. Convert this site to English
2. Condense, synthesize, and explain in layman's terms your findings on Petzvals

!!

Garrett

[goamules]

A developing goal for me is to demo all of my petzvals, sort of like what Jim Galli does, in a more qualitative mode. You know, determine which are more swirly. Which falloff closer to center (curved field), which are sharpest, etc. It's difficult when I throw in the process variables of wetplate, so I was waiting to do this with film. But I want to control the experiment by shooting identical scenes. Fun stuff for me, really....

[Dan Fromm]

Garrett, go here http://www.dioptrique.info/base/list...e_ordinale.HTM and click on 1-249, 25-499, and so on. Scan down the left margin, look for the word projection. Also look at the lens cross-sections for obvious Petzvals.

You are asking a lot. Especially the bit about findings on Petzvals.

Cheers,

Dan

[goamules]

...
You are asking a lot. Especially the bit about findings on Petzvals...

I was just kidding, it is a lot. Also, can you solve the problem of world peace?

g

[Wimpler]

You can also browse the database by Name of Inventor. Here is a direct link for Petzval:

http://www.dioptrique.info/base/i/i_petzval.HTM

The inventor list is here:

http://www.dioptrique.info/base/i/inventeurs_.HTM

Gonna go read my book and report wether I can find more detail on variations...

[Wimpler]

OK... My book has 10 pages on the changes in the Petzval lens design over the years.

My time is limited, and reading german takes me some time. Here is some stuff to get the discussion started. Please note that this information comes from a very reliable source. I can however not garantuee I understand everything perfectly. The fact that none of this information is available on the internet, however, should not me a reason to mistrust it (as there is so little available).

1. The original Petzval lens design had 6 elements in 3 groups! (this lens evolved into the orthoskop and the petzval portrait lens)
2. The original petzval portrait lens was made by voigtlander (1841). The original lens can be seen in the 'Arbeit' museum, in Wien, Austria. This was in the year 1911, I don't know wether this is still the case. It is said to be in original condition.

I will add more information when I have more time.

[Dan Fromm]

I was just kidding, it is a lot. Also, can you solve the problem of world peace?

g

Send money.

[Tim Deming]

I've noticed in about half of the petzvals I've owned (about 10), the rear elements were either reversed (from the correct period layout), or jumbled altogether. Not surprisingly, with the elements reversed, the swirlyness of the images increased greatly. With the elements in the correct layout (according to manufacturer drawings) nearly all of my lenses (mostly Voigtlander and Darlot) had little "swirl". I'm not sure if the elements were rearranged intentionally, or by mistake after a cleaning. Those interested in the petzval "swirl" might want to try rearranging the rear elements, they might like what they see.

cheers

Tim