Online Reference for overview of Darlot Lenses?

[Drew Bedo]

I will soon get,along (with some other stuff, a smallish brass lens, marked Darlot No. 2

I don't know much about these old brass lenses except that the old Petzval formula is now trendy for the "swirly Bokeh". . . .what the next 50-100 years of lens design tried to eliminate.

Is there an online reference that might give an introductory overview of the various models and configurations of the lenses from Darlot?

[goamules]

Not that I know of. There is a good book written by a nice lens scholar in France.

[Dan Fromm]

If you want to read it, write it. The references I cited in my Berthiot article and the on-line libraries that have them are a good place to start.

If you just want to know much of what can be known, buy the book. http://www.lereveedition.com/en/dossiers-collectors-11-a-20/n-14-jamin-darlot

[Drew Bedo]

Thanks Dan.


Related but tangent question:

How should I care for this lens' brass finish? I know what to do for my modern LF lenses and how to store a vintageknife or firearm. what is the best way to maintain or preserve the cosmetic appearance of the brass after using or just handling the lens?

[goamules]

Brass lenses originally had lacquer. There should be no maintenance required for the finish, just dust them. Over time, many start to lose their varnish. It thins or chips. Often people will have polished the brass over the generations. When you find a dark patina on a brass lens from the 1800s, you know it's been polished so much that the varnish was all removed. Or if it's "bare brass" it's been polished. I think all companies used a varnish, some held up better than others. For example, I have an early Dallmeyer from about 1863 that has all it's original varnish, and is shiny like the day it was made. Interestingly, many early American makers used thin varnish, and it's usually all worn off.

You can see on this one that handling or polishing removed the lacquer from the top of the lens, but it's remaining in other parts that are more protected.

https://live.staticflickr.com/3231/2718351406_6e8ac4df87_o.jpg

[Sanford]

I don't have any of these lovely lenses, but if I did, I would do what I could to preserve the patina as it is. I particularly like the way this one looks. I'd just rub it gently with some Renaisance wax and then put it to use

[Greg]

I don't have any of these lovely lenses, but if I did, I would do what I could to preserve the patina as it is. I particularly like the way this one looks. I'd just rub it gently with some Renaisance wax and then put it to use

Once purchased a brass Petzval lens that the owner had removed all the patina from. Owner honestly told me that he didn't like the image that the lens produced after he had "polished up" all the brass, so sold it to me at a bargain price. Tried the lens out and he was right. About a year later, on a whim, took the lens apart and found out that the elements and spacer were put back incorrectly. Once everything was correctly re-assembled, the optic had that "Petzval" Bokeh. Previous owner was more concerned with how cosmetically the lens looked and not with its performance.... Have a couple of brass lenses that I have cleaned the glass but otherwise do nothing else to them.

[Drew Bedo]

The wax suggestion seems to make sense. Is there any reason nOT to use a light film of wax?

[goamules]

Do you know what a wax will do to 130 year old varnish? Neither do I.

[Drew Bedo]

Do you know what a wax will do to 130 year old varnish? Neither do I.

No I do not . . .which is why I asked the question .

I tend to look on the possession of these vintage bits of photographica more as custodial, or stewardship rather than soverigne ownership. Sure I am using my gear, but I also look on it as holding my Kodak 2D for some one else, a future photographer, perhaps someone ot yet born.

The suggestion has been made to apply a wax coating to preserve the finish on an antique brass lens. A doubt about the advisability of doing so has been expressed. The question is whether or not this is a good idea.

Does anyone have experience of this, good or bad?

[lungovw]

I like the idea of removing the old varnish and applying a new one when the barrel becomes plenty of flaws and stains. But I see and almost understand that some people consider that a sort of sacrilege. My point is that even a Rembrandt has its varnish replaced when it gets dull, why not a lens?

[Drew Bedo]

Watch any presentation involving vintage or antique items. Condition and originality are paramount. For cars, its Original paint. For firearms, its how much of the original bluing is remains. For furniture . . .the same.

So here I have this150 year old lens by a desirable maker, Darlot, that has well preserved brass with good lacquer over all. I don't think I'll recoat that. Even if it was corroded or pitted, the original finish is paramount to determining its value. The glass needs cleaning if it is ever again to be used to create images. I may not do that.

Now I do have another old brass lens that has no maker's mark. It is not as old, is not particularly rare and has an iris diaphragm with marked f-stops. This will be, for me, a user that I will shoot film and drty plates with. I might consider refurbishing the brass at some point, but it actually looks great just now.

[pgk]

I rather like 'patina' as it suggests that the item has been used, and hopefully enjoyed. I don't refurbish things but do try to ensure that they works as intended.

[Tin Can]

Yes, I always prefer patina

But hate the big wet fixer thumbprint some ancient user imprinted on more than one piece of old gear I have