There is a nice early Dallmeyer Triple Achromatic Lens No.4 for sale on ebay.

[cgi.ebay.co.uk]

This lens was manufactured in 1864 and designed to cover 12x10.

It also has a flange. Perfect for someone who wants a nice early lens.

Sean



Edited 1 time(s). Last edit at 09/06/2007 02:35PM by sean.

do you know the focal length Sean?

Well Anthony's 1872 catalogue says the back focus is 15 inches, they were selling it for $76.00.

Is this considered a petzval lens?

No, this is not a Petzval, quite a different construction.

[attachment 496 tripleA.jpg]

Although unlike the Rapid Rectilinear in design the Triple Achromatic lens was a kind of precursor being used for copying as it did not distort, and although the maximum aperture was only f10 it could be used for portraits, groups and landscapes.

I have an article by written by J.H.Dallmeyer himself in 1863 describing the design of the lens and its uses. If you would like a copy I'll send you one as JPEGs.

It was really made redundant by Dallmeyer's Rapid Rectilinear design in 1866, although Dallmeyer carried on making and selling the Triple Achromatic lens until the end of the 19th.century.

Sean