Swift & Son Paragon No.4 Lens question

[dragosandriana]

I just bought this lens and I would like to know more about it.


What's written on it:
No.5082 SWIFT & SON London
No.4 Universal Paragon

What I know:
I found here on this forum a thread with a similar lens and there was an image with some info on this type of lens:


What I don't know and wish to find out:

A way to date the lens, maybe a catalog with serials and fabrication dates.
A place where I can read the story of "Swift and Son".
The front part is a little hit. If anybody knows a decent method to make it round again without ruining it.

Any help would be appreciated, thanks in advance.

[Steven Tribe]

Go to antiquecameras.net. Here you can order a download of the Lens VadeMecum which has a largish section on Swift & Co. for very little. They specialised more in other optical products (microscopes) than photographic optics.

Lens VM says the universal paragon is a fast (F6) RR and was available from at least 1889. There is no list of serial vs. production dates that I know of. Think Voigtlander series IV or Goetz Lynkeioskop series C.

[dragosandriana]

Thank you for your answer and advice.
I have another question about this lens. After I cleaned the lens (the glass), the front group looks perfectly transparent, while the rear group has a very slight haze (I tried to make a photo of it, but I can't find the angle and the position where it can be seen). It looks it's between the two glasses of the group and it also looks that the group can be taken apart, looking at the brass flange, although I tried and can't do it by hand. It's a little confusing, because it looks it is an aplanat (rapid rectilinear), but only a petzval would have the rear two lenses apart. An aplanat would have them cemented.



Another thing: in light I see four reflections (four images). Two wide apart and two close.



If it would have been an aplanat I should have only two reflections, I checked with my steinheil, which is an aplanat for sure. The cement cancels the reflection of the two cemented surfaces. Or am I wrong? Is a little confusing because the Lens VadeMecum says it should be a RR:

"Universal Paragon These were listed in 1889 as for Portraits, Groups and Panel Studies, and may have
been an f6 version of the RR. They were made in back focus values of 8.5in for 1/1plate; 10.75in for 10x8in;
13.25in for 12x10in; 16.5in for 15x12in; 20in for 18x16in; 24in for 22x18in; 30in for 25x21in, and 36in for
28x24in. At auction, one of these was listed as a "Universal Paragon No1 for 10x8 at No508x" and this may
be the one Hasbroeck illustrates as an f5.65 13in Universal Paragon No1 at No5081 on a Watson 8x9in
camera for dry plates about 1900-1910."

I also tried to check the bokeh, the safest way to check if it's a RR or a petzval. Unfortunately the lens is too large and I didn't adapt it yet for my camera. I'll try the bokeh test "in air" but I have to arange a small contraption for this, the focal is too long to do this with only two hands.

Any ideas about this subject?
And if any of you have the experience, how could I try to unscrew the two rear elements without ruining the lens?

Thank you again.

[Steven Tribe]

There are plenty of known mistakes in Lens VM - mostly for non-uk lenses. They were only guessing it was a Euryskop type design without having looked at one. You have done what they didn't and shown it is a slow Petzval!

Apart from dust between the two rear lenses, another sure sign would be that the iris position is not exactly halfway between the front/rear cells.

[Jim Galli]

I wouldn't abandon the fast RR guess. 150 years is time for lots of lives. I've had several lenses from that period come to me where the cement was long gone, and someone just cleaned up the residue with some acetone and put it back together for a quick sale on ebay. If you determine that's what you've got and want to have a play on the camera, just put a drop of Wesson cooking oil on the glass and put the halves back together. Not a permanent fix but works great for making a test shot.

[dragosandriana]

Thank you for your answers, I'll post here the final results after the test on the camera.
The iris is halfway between the front/rear groups.