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Richard Rankin
19-Mar-2011, 13:46
Ok, I couldn't resist this thing, but hey, it's from 1862 by the serial number, and who can resist this really old stuff? According to the Lens VM, this was a sort of early triplet used for early copy work, and eventually replaced by RR lenses and had no intellectual connection to the later triplets.

I showed it to someone and their comment was 'it looks like its been submerged for a century with barnacles attached' and that kind sums it up. I like to think of it as well-aged patina...

This one is f10, about 8" from the waterhouse slot, no stops included of course. Stops for these had the serial number engraved on the stops as well as the lens.

Looking at it, I have no clue as to how to take it apart and clean the lenses. I also want to see how the triplet is constructed inside there. I've disassembled many lenses, but this one has me stumped. I don't see any retaining rings, etc to remove.

Anyone ever seen one of these and cracked it open? I'll use it dirty if I have to, but I'd really like to get it clean.

Thanks , Richard

goamules
19-Mar-2011, 14:06
1. Unscrew the rear barrel from the base mount (ground glass side).
2. Reach inside and unscrew the knurled section that holds the center glass.

There are two barrels, you want to remove the rear one. The center element comes out from the ground glass side of the barrel, not the front one.

CCHarrison
19-Mar-2011, 14:21
layout

Richard Rankin
19-Mar-2011, 14:22
Thanks, Garrett .

That looked like the only possibility but I wasn't positive there was a line between the knurled part and barrel to try and unscrew. I'll need to round up some tools to do that. It's not coming off by hand strength alone...

Have you used one of these, then?

Steven Tribe
19-Mar-2011, 17:34
CCHarrison's diagram is from Traill Taylor's book from 1892 and doesn't give much idea of how the lenses can be removed from the mounts when you get to them.
The good news is that the glass used at this time is often still perfect. The bad news is, that with 3 balsamed lenses, the likehood of a meeting a breakdown in the balsam increases!
And, if it is like my Ross doublet from the period, the brass has been turned down over the lens edges. They were at start of a technical revolution and didn't design lenses that were easily serviced - just quick to make.

Richard Rankin
19-Mar-2011, 17:38
There's no separation that I can see, but the glass has some small scratching, I think. It's hard to tell unless you clean it. Sometimes what looks like a scratch is just gunk.

Haven't been able to unscrew the lens yet. I'll have to give someone with more hand strength a go at it, or find a pipe wrench maybe.

Thanks for all the info.

goamules
19-Mar-2011, 19:37
Hi Richard,
Yes, I've had a few of these, currently a small No. 1 and a No. 3. I shot this one with a very clean No. 1 I had for a while, since traded for a larger No. 3.

You may be interested to try it without the center lens. Even Dallmeyer mentioned doing that in period ads. I think it will become softer that way, but haven't tried.

http://farm5.static.flickr.com/4093/4850465804_fc0ccc4a41_z.jpg

http://farm5.static.flickr.com/4096/4849846795_058e098534.jpg

Richard Rankin
19-Mar-2011, 20:01
I think this must be a #1 but it seemed to cover fine on my whole plate and according to the ad I saw on CCHarrison's place, it is for 4x5. Mine is also missing that front part beyond the front lens which, I guess, is a simple lens hood.

Hopefully, I can bust this sucker open, get it cleaned, and try it with and without the center lens.