Hermagis Serial numbers Need your help with a database

[Amedeus]

There are plenty of paired numbers on both the usual lenses and a double pair on the achromat. I think there is a good deal of "assembly" logic in writing actual focal lengths on lenses or combinations (Rear pairs). I am sure they could grind and polish accurately, they had to work with glass that must have had some variation in refractive index.

The numbers on photo 2 are from the rear pair, whilst the two sets on photos 3 and 4 are both from the Achromat.

The future project in "nailing the lens markings" could be a separate thread?

Looking at these numbers, no focal length combination that could work to come up with a total focal length that is reasonable in light of the size of the lens, so yes, this will need a separate thread ... the two digit numbers are killing that thought for now ...

Cheers,

[Steven Tribe]

The only figure which I could make sense of was the 209 - which appears twice on the achromat. The measured focal length of the achromat is around 209mm. Working back from published and actual total length of the combined lens (120mm) provides a figure for the focal length of the rear pair - but the figure doesn't match up with any of the other numbers.

I havn't found the blacking paper on any of my other Hermagises (to cover the clear gap between rack and barrel cut out) so they seem to worked out a better system after around 1855.

[Steven Tribe]

Strange, the same day that I suggested that internal blacking paper is associated with the early pre serial numbers, I find another one!

This was on ebay in october/november. Incomplete - missing the lens hood and the rear lens cell. The missing cell gave a good view of the bare brass, where the paper had been and the still mounted internal baffle showing where the paper strip had been.

https://www.ebay.co.uk/itm/ANTIQUE-H...97.m4902.l9144

[Amedeus]

Strange, the same day that I suggested that internal blacking paper is associated with the early pre serial numbers, I find another one!

This was on ebay in october/november. Incomplete - missing the lens hood and the rear lens cell. The missing cell gave a good view of the bare brass, where the paper had been and the still mounted internal baffle showing where the paper strip had been.

https://www.ebay.co.uk/itm/ANTIQUE-H...97.m4902.l9144

I just checked my incomplete 12,651 and there is indeed clear evidence on both halves of the brass barrel that there was a covering over the rack. The brass there is bare. The 8,154 is just received doesn't have any sign of paper but there's solder covering the gaps. This could have very well been a post-production fix.

Cheers,

[Amedeus]

The 8154 is a convertible Petzval after all, the racks are screwed together. Hood is gone, no flange. Glass is 105mm in diameter, a #3 in the series with a supposedly 450mm focal length, f4.2.

After some struggle to get the cells open, I found the front achromat only bearing the inscription "Hermagis", absolutely nothing else. (No separation whatsoever)

The rear was assembled incorrectly but the rear negative lens bears following in pencil, although at times hard to read as the upper half of the text had a lot of damage (tight fit in the cell)

"Hermagis - Opticien Breveté - Rue Rambuteau 18 - Paris"

Followed in what appears to be capitals "GCC" or "OCC" (faint) and then what I thought was 1819 but the second 1 is different than the first 1 and could be a squiggly 5 ... the 9 is better to see in person after rotating and changing the light ... the image below is not the best iPhone shot either ...



So possibly 1859 and not totally out of line with the notion that 8,000 is around 1860. We need some more lenses in the same serial number range to confirm. We by now know that the information on the lens rims changed from time to time and nothing can be assumed.

As for focal lengths ... the front achromat is ~673mm, the rear cell is ~1,000mm and the calculated FL should be 453 with a ~190mm between cells. Measured FL is ~447mm so all is according to the catalog.

Both front cells have a Roman VI stamped in them, most likely to keep them together.

Cheers,

[Steven Tribe]

I don't think I have seen stamped roman numerals before. The ones I have have scratched ones and indicate which male/female threads are a best fit (hand cut threads!).

Yes, I would guess it was a convertible as Hermagis don't appear to have made anything else for the first period after 1857.
Have added to the #20 list.

Address information is unique, I think.

Perhaps a new member of staff, recruited from Jamin who did this sort of thing! Hermagis was in a growth period!

Later: We all appeared to have missed an earlier thread with some interesting data.
Alex has (had?) a plain Petzval with lens writing of "1856" and had the Rambuteau address-no serial number. Must been one the last before Convertible production took over.

http://collodion-art.blogspot.dk/201...t-bievres.html

Here is the previous thread link.

http://www.largeformatphotography.in...-Hermagis-lens

The other lens described by Vitaly is interesting as it appears to have the size written on both lenses! he says the lens diameter is 80mm and focal length is 11" with a 3" on both lenses. Size 5 has a focal length of 240mm, glass diameter of 81 (unmounted) or 3 pouce (french inches). So perhaps we should be looking for "lignes et pouce" rather napoleonic cm and mm?

[Amedeus]

I don't think I have seen stamped roman numerals before. The ones I have have scratched ones and indicate which male/female threads are a best fit (hand cut threads!).

Could be deeply carved roman numerals rather than stamped.

Later: We all appeared to have missed an earlier thread with some interesting data.
Alex has (had?) a plain Petzval with lens writing of "1856" and had the Rambuteau address-no serial number. Must been one the last before Convertible production took over.

http://collodion-art.blogspot.dk/201...t-bievres.html

Here is the previous thread link.

http://www.largeformatphotography.in...-Hermagis-lens

Very similar address writing on the 8154 except for "Breveté" after Opticien and a few added characters.

The other lens described by Vitaly is interesting as it appears to have the size written on both lenses! he says the lens diameter is 80mm and focal length is 11" with a 3" on both lenses. Size 5 has a focal length of 240mm, glass diameter of 81 (unmounted) or 3 pouce (french inches). So perhaps we should be looking for "lignes et pouce" rather napoleonic cm and mm?

Great observation, lignes, pouce and cm/mm could be indeed used interchangeably based on who was doing the writing or what needed to be done to separate the work in progress.

Cheers,

[lucaas]

I have two petzval type portrait lenses.
objectifs a portraits no.6, 57620, 1917
extra rapides pour portraits no.4, 65758, 1920

and an eidoscope no.2, 41650, 1907

[Amedeus]

I just realize that I bought this lens from the buyer at Steven's link below ... supporting the upcycling economy ... (reconfiguring the lenses and polishing it up ... )

The rear lens cell from this is marked Jamin in pencil, no further markings anywhere else.

Both front and rear cell have a roman III stamped/cut in them.

Hood as we know is missing but I'm very tempted to recreate the hood in black anodized aluminum, matter of keeping history and modern age restorations separated.

I'll be shooting with this lens soon, that's in the end the purpose after all ;-)

Cheers,

This one

http://www.ebay.co.uk/itm/BIG-BRASS-...vip=true&rt=nc

could be an early Hermagis serial no. 4307.

The rear and front cells have been assembled wrongly.

I base my case on:

- the very heavy duty rack is cut away near the lens cells. This identical in appearance to the earliest Hermagis I have.

- the use of double screws to secure the rack to the barrel at both ends. I have only ever seen this on early Hermagis lenses.

- the general appearance is not in conflict with Hermagis early brass.

- The lens diameter is 81 mm which matches one of Hermagis standard Petzval sizes.

- marking the barrel, rather than the sleeve, was done in connection with "monture universelle". The hood assembly, which would shed light on this, is unfortunately absent.

- the serial number is a number which is realistic considering the "known" numbers.

What does the glass edge writing say.

It is, unfortunately, not my purchase!

I don't believe this ever sold as a Hermagis. The rough numbering and the slightly out of true rack screws suggest it might have been a construction attempt that never found its way out of the workshop for retail sale.
-

[purplecloud]

here is mine
SN 9335 convertible petzval
height 215 mm
front lens diameter 80 mm