Your Oldest Lens

[Steven Tribe]

The Darlot script looks correct. Ir would be a mistake to assume the 48 is the year. Some even have the name of a person (polishing/assembly/inspection) and micro engraving/etching of letters/symbol codes on the outer rear surface.
Darlot was a big supplier of unmarked lenses to retailers who often put their name on them. I have a "Marion" vesion where the flat inside of the brass lens hood as a tiny AD stamping.

[Jon Wilson]

The Darlot script looks correct. Ir would be a mistake to assume the 48 is the year. Some even have the name of a person (polishing/assembly/inspection) and micro engraving/etching of letters/symbol codes on the outer rear surface.
Darlot was a big supplier of unmarked lenses to retailers who often put their name on them. I have a "Marion" vesion where the flat inside of the brass lens hood as a tiny AD stamping.

Steven, do you believe this Darlot would have been made in the 1850's? Here are a couple more images of the barrel/pill box.
Jon

[Steven Tribe]

Can't have been made in the 50's as Darlot evolved from Jamin/Jamin-Darlot in the early 1860's.
There is a "slot" in the small washer stop housing and apparently a "pressure strip" system (or is this just a brass strip which has been soldered in, in place of an F adjustment system?).
Could be any time from 1861 - 1890's.

[goamules]

Jon, the early ones are labeled Jamin on the glass edge and barrels. Since yours reads Darlot, it is later, the dates Steve gives are the period Darlot made this. Yes, they made them up until quit late, into the dryplate period. Jamin and Darlot are at this time difficult to date accurately. Their serial numbers seem to have started and stopped several times with gaps, overlaps, high starting numbers, low restarting numbers, etc. The ones engraved with an address can help.

[Jon Wilson]

Thank you Steve and Garrett. Then this one is definitely newer than my HBH lens.
Steve, it appears to be a "brass strip which has been soldered in." There probably had been a focus adjustment knob that was removed and covered up with the "brass strip" for the inside of the barrel reveals a screw hole and small rectangle where the gear/teeth could have fit. In any event, it is another one I will be trying out. Thank you again. Jon

[Steven Tribe]

I have looked at all the photos once more.
I don't understand why the barrel has signs of an earlier rack & pinion track in something which can only be called a sleeve. A "track" placed here would make no sense as the barrel has the usual thread system to be attached to a flange. It cannot be a focussing device. I thought perhaps it might be part of a larger Darlot Petzval/Landscape set - where the extra barrel and "rear" lens pair have got mislaid. This could explain the lack of engravings - they are on the other barrel section! I have never seen of these, and they exist in many variations. If this is the case, then we are probably talking about the 1860's. Darlot dropped these designs quite early.

[Two23]

Maybe either Darlot or a lens owner made a meniscus lens out of a broken Petzval? The rack & pinion were clearly once there.


Kent in SD

[goamules]

I have looked at all the photos once more.
I don't understand why the barrel has signs of an earlier rack & pinion track in something which can only be called a sleeve. A "track" placed here would make no sense as the barrel has the usual thread system to be attached to a flange. It cannot be a focussing device. I thought perhaps it might be part of a larger Darlot Petzval/Landscape set - where the extra barrel and "rear" lens pair have got mislaid. This could explain the lack of engravings - they are on the other barrel section! I have never seen of these, and they exist in many variations. If this is the case, then we are probably talking about the 1860's. Darlot dropped these designs quite early.

No, a focus knob was a common part of some pillbox lenses. Here is one I had:



And here are more: http://www.photographica.nu/unk257.htm, http://thenewpictorialism.blogspot.c...ld-lenses.html, etc.

[Jon Wilson]

Steve, here are a couple more pictures of the "rack & pinion slot" patch. Picture 1 shows the exteriod side of the barrel patch, while picture 4 shows the slot and screw hole which were closed with the patch. On the opposite side of the barrel is a "weld" or "braze" line, inside (picture 2) and exterior (picture 3) of barrel.

I don't know if there was another sleeve with lens that are long gone, but I hope you and others can educate me while shedding light on this large achromatic landscape lens.

I was able to finally place this lens on a 6x6 board. It appears that the focal length of this lens is around 16 inches. I was able to take a couple of images with the barrel removed. Those images on the gg created an ethereal glow/diffused image that one typically finds with a meniscus/achromatic lens. Then, I was able to take a couple of images with the barrel in place, but the "pill top" removed. That landscape image was calculated to be f12 +/- while with the barrel removed, it calculated to be f5 +/-. I hope to develop those WP negatives later this week.
Jon

[Steven Tribe]

I assumed there was no inner barrel and all the brass we can see was just a one piece and the front piece just screwed into this.
Looking at the interior finish, it could be the barrel and sleeve have been turned in relation to the various cut out holes for the rack and pinion mechanism and then soldered together.