Ross London CdeV No. 2 Your thoughts Please?

[Daniel Unkefer]

Hi All,

I just won this old brass Petzval lens. At $135 plus shipping I think I did very well. I'm very good at finding flanges and I have several local sources in my town. I believe from my internet perusing it is a Ross London CdeV No. 2 or something closely similar. The cell diameter is approx 2.25" and overall length 5.25".

https://farm5.staticflickr.com/4850/31379154987_ba45d8fa28_c.jpg (https://flic.kr/p/PNSnxz)Ross Lens 1 (https://flic.kr/p/PNSnxz) by Nokton48 (https://www.flickr.com/photos/18134483@N04/), on Flickr

https://farm5.staticflickr.com/4904/45405367655_99be06ee02_c.jpg (https://flic.kr/p/2cbjnUt)Ross Lens 3 (https://flic.kr/p/2cbjnUt) by Nokton48 (https://www.flickr.com/photos/18134483@N04/), on Flickr

My intention is is to use this lens on my 4x5" Sinar Normas cameras. Your thoughts?

[Steven Tribe]

I'll check my no.2 - perhaps tomorrow!

YOu will have this thread moved to the right section!

Done! --Oren

[Mark Sawyer]

I think you did pretty well. If you haven't found it yet, there's quite a bit on the old Ross lenses at:

http://antiquecameras.net/rosslenses.html

[Steven Tribe]

This was a lens I was watching. It certainly looks the part and I have been back to the listing to check the other photos.

Problems are the following:

- Rofs/Ross lenses are always engraved as such. They did not supply lenses to camera sellers without any engraving. This lens has no sign of an engraving. The engraved area on a Ross lens was originally quite small and a few lenses from before 1857 have lost their engraving when they have been converted to WHS. But this has no cut-out in the brass sleeve.

- So if it is a unengraved Ross lens it must be before 1857. But there arise some new problems. I remember Ross CdeVs from this period as having only 2, rather than 4, screws on the pinnion cover. Early Ross CdeVs have a rather thin brass hood, which has often been loss - this one looks quite substantial in brass gauge, but a lot too small in width and length.

- Finally there is the rather huge aperture restrictor in the lens barrel which will bring the speed of the lens down from around F3 (Or less!) down to over F4.5.

I think it is a projection lens - attractive and in OK condition - around the 1890's. You can easily knock out the internal baffle to get some speed! I can't really deduce coverage from the somewhat unclear listing description.

[Daniel Unkefer]

OK Thanks Guys!

So I wondered why no WH stops or engraving. Yes I think I can prolly remove the internal baffle (wondered about that!); I metal cut a lot of my equipment in my workshop to get it where I want it to be. Functionality is my only goal, dosen't have to be authentic in every respect. I hope it will work on my 4x5 Normas and 4x5" Profia Plaubels for portraits, and I will be happy; on both kinds of cameras I use the Sinar Norma shutters. Perhaps in a portrait scenario (moderate close up) it will cover 4x5/9x12? We will see. Swirly Petzval edges would be a bonus to me.

It seems the right dimensions and overall "look" to be a short Ross Petzval. Yes Mark, I have read about their lenses from the old article, I know extravagant claims were made back then!, but it sure sounds like exactly what I want. The best of the best of the best according to the article.

https://farm5.staticflickr.com/4884/32476727508_95b6d06daf_c.jpg (https://flic.kr/p/RtRHBJ)Ross Portrait Lens (https://flic.kr/p/RtRHBJ) by Nokton48 (https://www.flickr.com/photos/18134483@N04/), on Flickr

Certainly looks similar to this one! :)

[Two23]

I would try it as is before doing any cutting. Should be easy to unscrew and clean. Covering 4x5 might be iffy, but should be close.



Kent in SD

[goamules]

We were talking about your lens on your post on the Rangefinder forum, before I saw it here. Like people said above (and I did on the other forum), it's not a Ross if it's not engraved Ross. There are other differences if you look at the one you just showed, compared to yours, like the groove right at the front edge of the outside barrel, the knurling of the rear fixture, the stepped ring of the front element, and more. All Petzvals look very similar, you can't just say "It looks like a xyz" without some very good parameters being shown to match. To me, it looks like a French lens, but again...I could be wrong.

[Two23]

I too am skeptical that it was made by Ross--I believe I what see, not what an ebay seller writes. Be that as it may, it definitely is a Petzval and I think you're going to enjoy it. You got it at a good price. Certainly didn't get hurt.:)


Kent in SD

[Daniel Unkefer]

Thanks again Guys. I know a lot about my modern lenses, but never anything so vintage.

If it gives me swirly Petzval bokeh, covers at least 9x9cm or maybe 4x5, and can hopefully be made into a lens of about F3.0 or F3.5, then I will be completely happy. I'm really not concerned about who made it, just that it is functional for my needs.

I know Petzvals in this range tend to be very expensive.

It arrives Dec 24 from London, so Merry Christmas to me! :)

[Two23]

When it arrives, see if it's a convertible Petzval. To do that, unscrew the front lens group and unscrew the hood. Unscrew the rear lens group. Turn the front group backwards and see if it will screw into the rear of the tube. If it does, it's a convertible lens. It becomes an achromatic doublet landscape lens. Focus it on something far away, then measure the distance from the middle of the lens to the ground glass. (It will be a longer focus than when all four elements were used.) Using a micrometer or something, measure the diameter of the diaphragm in the middle of the lens. Divide length by diameter and you have the new aperture value. I would write that down on the back of the lens board so you don't forget. It will be fairly close to the Petzval. If the Petzval configuration is fl=6 inches & f4, the AC doublet should be something like fl=9 inches and f6.3, or something in that ball park.


Kent in SD

[Daniel Unkefer]

Nice! I will check that out. This is going to be fun for me.

[goamules]

Indeed, I've never met a Petzval I didn't like.

[Daniel Unkefer]

Indeed, I've never met a Petzval I didn't like.

OK Now I am getting stoked. Your flikr pictures are wonderful.

https://farm2.staticflickr.com/1979/43851423630_6880c074a3_c.jpg (https://flic.kr/p/29P11u7)New Showcase for Plaubel System (https://flic.kr/p/29P11u7) by Nokton48 (https://www.flickr.com/photos/18134483@N04/), on Flickr

Here is my new office showcase for my Plaubel collection. As you can see, my collection is mainly 1960s-1970s vintage lenses, and a lineup of very modern hacked Fuji GX680 lenses. The Petzval will be totally new to me and I have nothing like it.

I want to do 6.5x9cm and 9x9cm J Lane dry plate photography, along with using modern sheet and roll films. I think the Plaubels will be perfect platform for this upcoming project. All I need is time, and that coming up soon in a very big way. I am retiring Dec 31! :)

[Two23]

A few Petzvals.

Kent in SD

[jhonsnicker]

Wow, you have a precious collection of lenses. The London 10523 is the really really awesome thing that i ever seen.
My best wishes are with you. Take a try and make a beautiful collection of snaps.

[Louis Pacilla]

. The London 10523 is the really really awesome thing that i ever seen.


OK maybe a few lenses in a cabinet but the Rofs/Ross lens is NOT his.
He was trying to convince himself and others who know better that a 1890's or later magic lantern lens he bought for a 1/5 the going price of a true Ross Petzval. The OP snipped this screen shot of an others Ross Petzval so 10523 is not his.

[pjd]

A few Petzvals.

Kent in SD

The cat does not look impressed! Good looking cat though.

[Daniel Unkefer]

OK maybe a few lenses in a cabinet but the Rofs/Ross lens is NOT his.
He was trying to convince himself and others who know better that a 1890's or later magic lantern lens he bought for a 1/5 the going price of a true Ross Petzval. The OP snipped this screen shot of an others Ross Petzval so 10523 is not his.

"Certainly looks similar to this one! :)" Did you see that?

I really don't care who made this lens. I'm somewhat interested in it's history, being so old. More important to me is it's functionality and if it will work for my uses. Several here and elsewhere have stated it's prolly not a magic lantern lens. If it is, I could care less, if it works for my needs.


"I've never met a Petzval I didn't like" Sounds good to me. I will report what I find.

[goamules]

It will be a good lens, today we get them for their primitiveness. It may vignette, have swirl, have a curved field, and other aberrations. Which is what makes them photograph so distinctively. I have Petzvals from 1" to 22" focal lengths, and have shot them on all formats. They're really fun.

[Daniel Unkefer]

Wow, you have a precious collection of lenses.

Thanks! I've been collecting large format lenses (specific to my interests) for thirty five plus years. I suppose I have close to fifty lenses total, the rest are in my studio in the basement. The Plaubel collection I wanted in my office, as a reminder to get out and start using them! :)

[Daniel Unkefer]

It will be a good lens, today we get them for their primitiveness. It may vignette, have swirl, have a curved field, and other aberrations. Which is what makes them photograph so distinctively. I have Petzvals from 1" to 22" focal lengths, and have shot them on all formats. They're really fun.

Sounds great. Can't wait. Much fun ahead.

[Daniel Unkefer]

https://farm1.staticflickr.com/525/32575847695_059b2def26_c.jpg (https://flic.kr/p/RCBJAt)Makiflex Petzval (https://flic.kr/p/RCBJAt) by Nokton48 (https://www.flickr.com/photos/18134483@N04/), on Flickr

Here's another Fellow on the Internet with the same idea as mine.

https://farm1.staticflickr.com/606/32535166606_7eb37005e2_c.jpg (https://flic.kr/p/Rz2ewo)Makiflex Petzval 2 (https://flic.kr/p/Rz2ewo) by Nokton48 (https://www.flickr.com/photos/18134483@N04/), on Flickr

Very nice result!

[Daniel Unkefer]

https://farm8.staticflickr.com/7910/44685338590_65132e4ac7_c.jpg (https://flic.kr/p/2b5G3mf)New Petzval Lens on Std Makiflex (https://flic.kr/p/2b5G3mf) by Nokton48 (https://www.flickr.com/photos/18134483@N04/), on Flickr

OK It's here! Viewing through it, I absolutely love it! Surprisingly sharp on the glass. Shown on Makiflex Standard Body, lens focused on infinity target. I am so glad I took a chance on getting this one.

Later today, I removed the glass elements, nothing is marked anywhere. The central stop looks like it's much later to me, and rather homemade. Made of silver metal and coated with candle soot. I removed that rather easily from inside the barrel, and now I should have an F3.0 or F3.5 lens. Without the central stop, the lens is sharp in the center, and rather swirly at the edges as I have seen in so many Petzval examples.

Now I need to find a proper flange and clean it a bit more. I am super pleased.

[Two23]

You're on a roll here.:o


Kent in SD

[Daniel Unkefer]

You're on a roll here.:o Kent in SD

I'm having fun :)

https://farm8.staticflickr.com/7833/45614007705_07869702bb_z.jpg (https://flic.kr/p/2cuKHjH)Unmarked Petzval Sinar Norma Board (https://flic.kr/p/2cuKHjH) by Nokton48 (https://www.flickr.com/photos/18134483@N04/), on Flickr

Here is the unmarked Petzval attached to a Sinar Norma Board, using a copious amount of Gorilla Tape. So now I can mount it on my 8x10" Norma, 5x7" Norma, and 4x5" Normas. It will be interesting to determine it's actual true focal length and to examine the full image circle.

[Daniel Unkefer]

https://farm5.staticflickr.com/4176/34521427212_c1b3c65964_z.jpg (https://flic.kr/p/UAxkAU)DSC05763 (https://flic.kr/p/UAxkAU) by Nokton48 (https://www.flickr.com/photos/18134483@N04/), on Flickr

This is what I will use to examine the image circle of the Petzval.

Question -- Where in the lens barrel do you think the nodal point of this lens would be?
Nodal point of the lens to film plane point focused at infinity should determine actual focal length if I remember correctly.

[Two23]

https://farm5.staticflickr.com/4176/34521427212_c1b3c65964_z.jpg (https://flic.kr/p/UAxkAU)DSC05763 (https://flic.kr/p/UAxkAU) by Nokton48 (https://www.flickr.com/photos/18134483@N04/), on Flickr

This is what I will use to examine the image circle of the Petzval.

Question -- Where in the lens barrel do you think the nodal point of this lens would be?
Nodal point of the lens to film plane point focused at infinity should determine actual focal length if I remember correctly.

Anywhere in the middle should be close enough.


Kent in SD

[Daniel Unkefer]

OK Thanks again. Your Petzval collection is very cool.

[Daniel Unkefer]

Been outside with 8x10 Norma. Focused at infinity, the mystery Petzval lens has about an 8" image circle. I can clearly see the edges of the circle (extremely swirly). Dead razor sharp in the center. Measured focal length 180mm-190mm range depending on where the lens' nodal point actually is. So quite useful focal length for my potential many uses.

Bright image on the groundglass! And I do think it is prolly a convertible Petzval, because the front and rear cells can interchange.

Comments Welcome!

-Dan

[Steven Tribe]

Almost all later Petzvals have the same thread for the front and rear lens cells. The front achromat cell is always useable as a landscape lens. But fitting the front achromat at the rear doesn't make a Petzval a convertible version - the normal Petzval barrel is far too long for getting a reasonably sized image. The convertible Petzvals have a split barrel and, sometimes, an extra flange mounting thread around the lens hood.

[Daniel Unkefer]

Thank You Steven!

Not being convertible is not a deal breaker for me. I have wanted this lens (for a while now) so that I can make more unique images with it, versus my plethora of 60s-70s (and very modern lenses). I am enjoying just looking at the ground glass with this one :)

Off to my local LF parts sources in my quest for a matching mounting flange, and maybe a missing brass screw that holds the knob against the barrel.

Soon I will shoot some test film and go from there.

[jhonsnicker]

When it arrives, see if it's a convertible Petzval. To do that, unscrew the front lens group and unscrew the hood. Unscrew the rear lens group. Turn the front group backwards and see if it will screw into the rear of the tube. If it does, it's a convertible lens. It becomes an achromatic doublet landscape lens. Focus it on something far away, then measure the distance from the middle of the lens to the ground glass. (It will be a longer focus than when all four elements were used.) Using a micrometer or something, measure the diameter of the diaphragm in the middle of the lens. Divide length by diameter and you have the new aperture value. I would write that down on the back of the lens board so you don't forget. It will be fairly close to the Petzval. If the Petzval configuration is fl=6 inches & f4, the AC doublet should be something like fl=9 inches and f6.3, or something in that ball park.


Kent in SD

Where did you find that? It's really unique, love it dude.
Send me the link to approach on it.

[jhonsnicker]

https://farm8.staticflickr.com/7910/44685338590_65132e4ac7_c.jpg (https://flic.kr/p/2b5G3mf)New Petzval Lens on Std Makiflex (https://flic.kr/p/2b5G3mf) by Nokton48 (https://www.flickr.com/photos/18134483@N04/), on Flickr

OK It's here! Viewing through it, I absolutely love it! Surprisingly sharp on the glass. Shown on Makiflex Standard Body, lens focused on infinity target. I am so glad I took a chance on getting this one.

Later today, I removed the glass elements, nothing is marked anywhere. The central stop looks like it's much later to me, and rather homemade. Made of silver metal and coated with candle soot. I removed that rather easily from inside the barrel, and now I should have an F3.0 or F3.5 lens. Without the central stop, the lens is sharp in the center, and rather swirly at the edges as I have seen in so many Petzval examples.

Now I need to find a proper flange and clean it a bit more. I am super pleased.


You really did amazing, how do you feel know?
on the other way i can't explained my feelings.

[Daniel Unkefer]

You really did amazing, how do you feel know?
on the other way i can't explained my feelings.

I feel very good about this new purchase. I really do think this one is super cool.

I have had no luck getting a flange from Midwest Photo, I stopped in and JimmyA tells me he sold all his stash of hundreds and hundreds and hundreds of flanges and unbelievable stash of LF lens parts. What a bummer. An incredible resource in now GONE. On the other hand, he told me who bought all the goodies and I do stay in contact with this person..............

But, I have contacted an old friend, who collects old brass lenses. We are meeting Sunday and he is bringing a baggie of flanges that are close to 79.5mm, which is what I need. Jimmy A measured it for me with digital calipers, it's 79.5mm. Flanges are difficult, my collector friend says they were sometimes one-off specific to a given lens. BTW he says he just made a giant brass lens purchase, that nearly doubled his collection of brass lenses. And believe he has a MAJOR collection. So a great time to hook up with him and have lunch :)

I'm now in retirement mode (four days now) and soon I will get going with all these projects. Got a honey do list to work thorough but I am getting there!

I know I am going to enjoy using this Petzval. I have no regrets. And there are many ways to mount a lens to a board, when you don't have a flange. We will see on Sunday when I meet with my friend.

Life is good :)

[goamules]

The only flanges that I've had luck matching to a lens are British. The TTH were patented, and the Dallmeyers were standardized. Out of hundreds of tries, I've only gotten a couple more that kind of, sorta fit a lens that had the flange missing. Even had a machinist make a flange for a big Cooke, but it didn't fit. I'd find an alternate method. I often just make a snug hole in the lensboard, then put a rubber hose clamp on the rear of the barrel, to hold it against lens thread rim, at the front.

[Two23]

I have flanges made for my best lenses, and mostly those come from SK Grimes.


Kent in SD

[Daniel Unkefer]

SK Grimes is a very real possibility. May I ask approx cost and time? JimmyA said they would need the lens (of course!).

My collector friend says he has screwed brass lenses in a soft aluninum plate, and then mounted the plate. And I guess there is always my friend JB Weld but that is a absolute last resort.

So I have few cards yet to play on this deal.

Maybe I will luck out Sunday. Or maybe this other Guy will let me look through all his flanges.

[Two23]

I have wondered if a light duty substitute would be to drill a hole into a lens board very slightly smaller, grease the brass threads well, and then epoxy in place. For small Petvals on thin technika boards I've tightly wound tape around the threads protruding through the rear.


Kent in SD

[Daniel Unkefer]

https://farm8.staticflickr.com/7835/46602047111_2fbf9fea0f_z.jpg (https://flic.kr/p/2e14F1T)Light Duty Petzval Mounting Plaubel Board (https://flic.kr/p/2e14F1T) by Nokton48 (https://www.flickr.com/photos/18134483@N04/), on Flickr

I found this Plaubel board, which very tightly friction fits the main tube of the Petzval. (Had to remove the rear cell group). Screw the rear group back in, and I'm in business. This will do while I investigate options for a flange.