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lukefeeney
26-Feb-2018, 13:20
Hi,

I'm looking for information about Hermagis Petzval Lenses to assist me in purchasing the right one for an 8x10 camera. For me it has been easier to find information on Dallmeyers and Voigtlander lenses. But for some reasone I'm struggling to find clear information on the Hermagis range of lenses.

If Anybody can shine a light on the range of Hermagis Petzval Lenses and how to differentiate them would be fantastic. I would really like to know the focal lengths and speed also if possible.

Regards to all.

goamules
26-Feb-2018, 13:33
They weren't imported into the US as much, so you don't get 1800s catalogs showing them as much. All makers tried to make their Petzvals at least F3.6 or so, the standard Petzval. Some a tad faster, some a tad slower. Few French lenses showed the speed in the early days. Hermagis typically don't say anything on their barrels besides their name and Paris and serial. You just pay your money and take your chances. They all made a range of Focal lengths to cover the plate sizes of the era: 1/6th plate, 1/4 plate, Half Plate, Whole Plate, Mammoth, etc. Again....seldom written on the lens.

Steven Tribe
26-Feb-2018, 15:58
Perhaps this link will help you a bit.


http://www.largeformatphotography.info/forum/showthread.php?106533-Hermagis-Serial-numbers-Need-your-help-with-a-database&highlight=hermagis

Three series of Hermagis Petzvals are described.

Hermagis made a lot of Landscape lenses at the start of his career, but not many Petzvals. These are without any serial numbers.

He designed and patented a convertible Petzval in 1858 and started serial numbers at the same time. These can be identified as the have an extra flange thread at the base of the lens hood. They are very heavy lenses due toquite a lot of extra brass.

There were two normal Petzvals series called series II from around 1860 and from 1880. These have speeds between f3.5 and f2.7.

I enclose the (transcribed) catalogue data for these. These are from the Hermagis booklet from le reve edition and the quality of the images below is due to respect for their copright!

photo two is the data for the convertible Petzval. The design was popular and continued until around 1900. The coverage is given for portrait and lanscape modes.

photo one and three show the slightly different sizes available for the F3.5 version.

Note Hermagis used size 1 as the largest, except size 00 for the Hermagis Eidoscope series! A size covering 8x10" will have a lens about 11cm across. I have the convertible in this size and it weighs over 4 kilos!

lukefeeney
26-Feb-2018, 18:43
Hi Steven,

Thanks for the information. Very interesting indeed. I'm not sure my camera will like a 4kg lens on the front.

Luke

Steven Tribe
27-Feb-2018, 02:19
Lens board size can also be a problem. The external diameter of the 8x10" Hermagis is 8".

Brass lenses with sleeves for front focussing have the advantage of being mounted so that almost 50% of the weight is past the lens board - that is, bulk weight is the same but torque on the front standard is much less.

The coverage is given by the makers in relation to the portrait demands of the 19th century. Many smaller lenses could stretched and, of course, slower lenses have much better coverage - like the D series Dallmeyer.

alex from holland
28-Feb-2018, 01:05
Steven, i don’t think you really need a petzval that big to cover 8x10”.
I have been using 300mm hermagis petzvals for 8x10 without any problem.

Steven Tribe
28-Feb-2018, 01:50
Yes, I know and did mention it in the post. I realise that just about all 300mm (12") Petzvals can be pushed to cover 8x10".

The classic example is the Dallmeyer 3B which sells well to larger formats, although it is given as a full plate lens. One of the problems with the sizing of Petzvals is that they were made with reference to Medaillon, CdeV and Cabinet sizes, then to 1/4, 1/2, etc. plate sizes. Certainly, the 1/4 plate doesn't doesn't cover the modern 4x5" format!

I feel safer quoting the published figures!