Landscape lenses with missing apertures

I've collected few landscape lenses or single meniscus soft focus lenses with missing apertures. Either broken, lost or part of the uncorking to turn a landscape lens in a pictorial portrait lens.

I've documented what I did with two of them on my blog. Sharing here so it can give inspiration to others tempting to do something similar.

There are many ways to skin a cat, this is just one of them.

Cooke RV to RVP

http://amedeusphoto.zenfolio.com/blo.../cooke-rvp-tlc

Ross landscape lens with an early serial number

http://amedeusphoto.zenfolio.com/blo...cape-lens-1520

Working on a few SF lenses, documenting these later.

Open to questions, suggestions and any other type of dialog.

Cheers,

It is always nice when people write about lenses that I own as well!

Some very good solutions/improvements for some classic lenses.

I have had some bad experiences with the T,T & H bronce irises too. But the iris I have with a casket set (WAR, RR and RV) is actually perfect - which means that I might have been stuck with F11.3 for the RV. Unlike the Dallmeyer range, the iris is absolutely fixed and not to be tampered with! But fortunately in the casket set the RV can used without the section of the barrel which has the iris "embedded"!


Ross didn't make many of the Landscape lens, but I have a very late one no. 23230, which is obviously very related to the versions you illustrate. It is push/pull focus in a plain sleeve. A fixed aperture (F20 perhaps) with a insert cup with smaller apertures. This insert has the T cut in the brass, which was standard practice for telescopes (decent ones, anyway) in the 19th century. It has the raised lens cell and a raised edge to prevent the barrel falling out of the sleeve. This insert cup idea was adopted by French makers for Petzvals around 1854, just before they started split barrels and then, suddenly, were knocked over by Mr. Waterhouse.

Here is a photo, as it is, incredibly, one of the 5 lenses I have down here in sunny Spain at the moment!

Excellent solutions all. My new to me Pinkham SA is pre-serial number and the aperture blades are all gone. My thought was to find a donor iris with blades that could be transplanted as all the pieces are present. But it seems that when the boys put that part of the iris together, very likely on a thread, they then machine rolled the edges in so that it will never be possible to do a repair without destroying the historic integrity of the lens body, which I am loathe to do. One bit of luck is that I would likely do about 95% of my shots wide open anyways. Now the rear barrel unscrews easily from the iris housing, so the possibility of mounting an early shutter with iris, probably a Betax 4, or even a Copal 3 perhaps is very simple. You would simply take off the unusable original iris housing and screw the shutter in place with machined adapter so that the shutters iris is in the exact position where the original would have been had it survived. My 12" S.A. had this done about 1930 by Pinkham's shop. They returned it in a heavy cardboard box with the catalog that I have scanned many years ago. They used an Ilex 5 to do the job.

A little addenda an hour later. I measured a bunch of old stuff I have sitting around and a Betax 4 has a perfect 45mm aperture that matches that lens perfectly. My thought is to simply thread up an ABS plastic sleeve to thread into the rear of the Betax and machine it the exact diameter of the current barrel so that it simply slides on and off. Plastic is light and it won't gouge the soft aluminum original barrel with the engraving.