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View Full Version : Any ideas -- It is a Petzval but by whom??



Shen45
4-Jul-2008, 01:11
This is an interesting little lens. Physically about 4.5 to 5 inches long about 2" at the front with an aperture scale from 4 - 16. It does not have a thread on the rear for mounting but at about 140mm at infinity it covers 5x4 with slight movements -- :) slight.

It is a Petzval configuration as far as I can determine. I have had the rear group apart. It has the very definite Petzval swirley bokeh.

There are no engravings on the barrel or inside the barrel that I can see.

So -- any ideas what it may be?

CCHarrison
4-Jul-2008, 03:17
I cant tell if the pin that moves the aperture is original or not from your photos, but that type of aperture style was popular more towards the 1880's. These lens types were made in significant quantities over a significant number of years so, it could be made by anyone...my guess.... 1875-85 Made in UK.

My Petzval Portrait Lens Page
http://members.aol.com/summaron7/petzval.htm

Dan

Mark Sawyer
4-Jul-2008, 09:14
I'm slightly surprised it's not a rapid rectilinear, which was a bit more common by the time the diaphragm aperture came in. They will swirl too...

Lensmakers often didn't engrave their lenses, leaving that for the distributor, who sometimes didn't do it either. It will probably remain a mystery lens...

Shen45
4-Jul-2008, 20:20
Thank you for the input on the lens Dan and Mark. I think the origin is probably UK as Dan suggests because of our past association with the UK.

Mark the rear group on this lens consists of 2 elements separated by a metal spacer -- about 2mm. The front seems to be a single lens but I cannot take it apart.

This image was taken with the lens.

Mark Sawyer
5-Jul-2008, 00:28
Mark the rear group on this lens consists of 2 elements separated by a metal spacer -- about 2mm. The front seems to be a single lens but I cannot take it apart.


If the front is a single element, it's a triplet, not a Petzval. Triplets were pretty common as projection/magic lantern lenses, but some were also camera lenses.

But if it's a cemented doublet up front, you've got yourself a Petzval!

Neil Purling
5-Jul-2008, 14:41
Is this image a crop of the top half or top quarter of the full frame?
Roughly what is the focal length of this lens?
The minimum FL to cover the full frame of 4x5 must be at least eight or ten inches.
If this is indeed a Petzval the FL would have to be far more than that to have a large area of sharpness.

Shen45
5-Jul-2008, 17:45
I believe from what Mark has described and examination very closely of a "real" Petzval I have that this is a Triplet.