Info on very early Petzvals?

[Mark Sawyer]

A friend at the University of Arizona's Optical Sciences Department recently queried me about early (1840's) Petzvals as follows:

"I would like to find out where in the early Petzval lenses the diaphragm was located. There are two options: a) near the first lens, b) near the middle between the lenses. The only way to know is by actually examining either:
1) The original Peztval-Voiglander camera
2) One of the replicas built in commemoration of the first
3) Looking at Petzval lenses of around 1841-1849 before the Waterhouse stops came in use."

Can anyone point me/him to some good information? (I've already sent him a link to Dan's Petzval history page.)

[goamules]

Actually, I believe Waterhouse stops were invented in 1856 or 1858 depending on who you believe. So any lens prior to this would be useful. But I'm not sure they had much of a diaphragm, I'll have to look at some of my early, uncut ones, but I think they were smooth barrels inside. The fastest design was certainly what they were after in the Daguerriean age. By the wetplate era of the early 1850s, they needed to stop them down some, and started retrofitting the old Petzvals with slots. So I'd look at any uncut Petzval up til about 1851. You're in luck, I have several!

[Mark Sawyer]

Thanks, Garrett! I'd already told him the early Petzvals may not have had aperture restrictions as the early processes were so slow, and one wouldn't want to trade away aperture for other benefits. But not knowing those very early lenses, I could be wrong...

[goamules]

I just looked at one I have out, a quarterplate NY radial drive uncut, and can't see any internal restrictions.

[Two23]

I have an 1847 Voigtlander Petzval. It has no diaphragm at all. Neither does my 1855 Grubb or 1850s Derogy Petzval. Since Dag-type was so slow, they just shot them wide open. That was the point--fast lens, faster exposure time on their very slow media.

Kent in SD

[maurits]

Mark, Garrett, I have two pre-Waterhouse Hermagis convertible lenses that use internal aperture disks.

The big lens on the left and in the middle has a set of small aperture disks to install in the lens hood when the lens is operated in landscape mode, using only the reversed front group (first image). The disks are held in place by a round steel spring.

Smack in the middle of the lens is another, much larger aperture holding device. These disks are to be used when the lens is in portrait mode. The barrel of the Hermagis convertible conveniently unscrews into two parts. Here, the rear part of the barrel holding the air spaced group is taken off the lens. Don't let the flange mounted on the back side of the lens board confuse you. It is just there as an extra safety measure.

The tiny (160 mm focal length) Hermagis convertible barrel also unscrews into two parts. You can see an internal aperture disk mounted and held secure by a steel spring.

On both lenses, when using the focusing device to retract the lens as far as possible into the camera, the aperture would be exactly on the same plane where the flange meets the lens board.

Maurits


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[maurits]

On the left the internal disk aperture from an early Alexis Millet internal bayonet mini-cone lens. In the middle a Darlot cone lens with a disk aperture installed. On the right the bayonet front group of a Derogy I used to have. It came with (I think) three disks. One can be seen mounted here.

In the case of the last two lenses, I think the disk apertures were primarily meant to be used when in landscape mode.

Maurits

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[Jason Greenberg Motamedi]

To my knowledge, there was no way of reducing the aperture of the Voigtlaender cannons. This is based on my playing with one of the "original copies." Previous to the 1850s there may have been washer stops on Petzvals--as there were with landscape lenses--but I can't say I have seen them.

[CCHarrison]

Ditto on what Jason said. The earliest Voigtlander Petzvals had no stops/diaphragms. However, some of the earliest landscape lenses did.

Dan

[Mark Sawyer]

Thanks, all! It sounds like no aperture restrictions were used in the earliest Petzvals, though in Mauritz's "convertible" Hermagis Petzvals there were washer stops for use in the landscape lens configuration.

BTW, was the term "landscape lens" used because landscapes would hold still for very long exposures at small apertures, while people couldn't? (Never thought about it before...)

[CCHarrison]

Keep in mind that Hermagis didnt even start making lenses until 1854/1855, and by that time, aperture controls (mostly discs inserted in the tube) were being used even on some Petzvals.

[Mark Sawyer]

Thanks, Dan; I wasn't aware Hermagis started that "late". By the mid-1850's, improvements to the Daguerreotype process made it significantly faster, and the collodion processes were faster still, so stopping down the lens was becoming practical.

[maurits]

The examples above are mostly late 1850's lenses. I think it is reasonable to assume that it took a while before most lens makers adopted the Waterhouse solution. So even in 1860, many lenses were made in the same manner as they were in the previous decade. At the same time, when the faster collodion process replaced the Daguerrotype, photographers started feeling the need to stop down exposure time.

The big Hermagis in my first post in this thread proves that washer apertures were also used for portrait Petzvals. This lens has separate aperture solutions for both landscape and for the Petzval configuration. It was designed that way. So the need to be able to stop down a bit was there a while before Waterhouse made life much easier.

[CCHarrison]

Here is my paragraph on aperture control for Portrait lenses ( from http://antiquecameras.net/petzvallens.html )

"The vast majority of (Portrait) lenses from the 1840-1855 period had no aperture controls. They were meant to be used wide open and didn't provide any means to stop the lens down. There were a few rare exceptions during that period. In those cases, the front lens group was unscrewed and a stop was inserted in the barrel and the front group was then screwed back into the barrel. In the mid-1850's, there were a few individuals* who apparently came up with the idea of inserting stops in the barrel of the lens. However, it is John Waterhouse of Halifax who is commonly credited with the invention, hence the name "Waterhouse stops."

In 1857, CC Harrison and Joseph Schnitzer (http://antiquecameras.net/1857ccharrisonlens.html)applied for a patent for what has become the "iris diaphram." Their patent was granted September 9, 1858; patent number 21,470. To this day, the same basic concept is utilized in almost all photographic lenses as Harrison patented. Harrison's main competitor in America, Holmes, Booth and Haydens, would also patent a form of an adjustable diaphragm on June 7, 1859; patent number 24,356.

It would take some time for the iris diaphragm to become commonplace since Waterhouse stops were simple to manufacture, inexpensive and did their job quite effectively. While the iris diaphragm eliminated the need to carry stops of varying sizes around, the complexity of manufacture and related expense would delay its general popularity until the late 1870's. From that point forward, most makers in Europe and the US, would offer their (Portrait) lenses with either Waterhouse stops or with the more expensive iris diaphragm.

Its important to note that since Waterhouse stops only needed a slit cut in the barrel to perform their function, so many early lenses of the 1840-1855 period may have had their barrels cut after they were originally manufactured.

In summary, portrait lenses with a slit for Waterhouse stops typically date no early than the late 1850's. Lenses with an iris diaphragm typically date from the late 1870's on, however, there are exceptions that date back as early as 1857. Photographic lenses with no aperture control would typically have been made from the 1840's to the mid 1850's.

* Lake Price, HR Smyth, and John Waterhouse all seem to have some claim towards the invention of lens barrel stops."


I would add that most manufacturers quickly adopted waterhouse stops. While you could still buy portrait lenses with no provisions for stops through the 1880's, almost all major lens makers offered the option of WH stops very quickly.


Dan


PS - I also recently blogged about my HB&H Petzval that had an aperture "cone" internal to the lens. These appear on sme HB&H lenses as early as 1857. See http://antiquecameras.net/blog.html

[CCHarrison]

And for extra credit, the images attached show an article written by John Waterhouse on July 1, 1858 to the Journal of the Photographic Society describing his "invention."

Dan

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[Two23]

BTW, was the term "landscape lens" used because landscapes would hold still for very long exposures at small apertures, while people couldn't? (Never thought about it before...)



I think the main reason for calling a lens a "portait" was that the exposure was much shorter, and it required the subject to sit still for the shortest amount of time. A landscape lens was taking photos of things that didn't move. There is more to it than that though. A wide fast aperture helps to blur the background and soften the image, both factors are nice to have for portraits. A landscape lens typically benefits from a smaller aperture which produces more DoF. I have a vintage 1854 E.G. Wood landscape lens that has three f-stops. It can be shot wide open (very soft!) It can be shot with an insert that stops it down to about f11, and finally there is a washer that can go into the insert that stops it down to about f22. The design is very early and is known as a double achromat or meniscus lens. Exposures would have been very long with this lens when it was new.

Kent in SD