about these Petzval portrait lenses....

[Frank_E]

Still a relative LF newbie. Have only shot 8 sheets so far. No problem developing them in my Jobo. I go in the darkroom tomorrow to try and print them...

Seeing some of these Petzval portraits causes me to also want to try that genre of LF photography. But after following the threads here for a while it seems to me that the lenses are relatively scarce or expensive (I shoot 4x5 by the way...)

Have been browsing ebay to see what older lenses are available. Most do not declare them to be a Petzval lens formula. So some questions:

1. What are the distinguishing descriptors which would suggest the lens might well have a Petzval formula?

2. From other threads here I learned that often brass Magic Lantern lenses might be suitable, but these typically don't have Waterhouse stops. How do you otherwise create these iris stops. Do they have to be behind the lens or can they also be at the front (easier) but will that somehow affect the image. It seems a shame to cut the barrel to place home made stops between the two lens elements. But I guess that could be done if you are so inclined. Have others done this?

3. I understand that the easiest (but not easy) way to establish a shutter mechanism is to somehow fasten a Packard shutter behind the lensboard. However there seems to be limited information which I have found about these shutters. What type of Packard shutter should I look for.

Thanks for the help..

[goamules]

Hi, you should be able to find a 4x5 sized Petzval pretty easily. The reason a lens doesn't ever have the word "Petzval" is because it was patent protected, but not internationally. Early manufactures used the design, but not the name. They were the common portrait lens for 60+ years, and have many trade names.

1. A key indicator is it will be a relatively long lens, compared to it's width. Long looking lenses are usually either a Petzval or Rapid Rectilinear. If you can handle one, the rear element will have two lenses, separated by a metal washer. The front will be a cemented double lens.

2. An iris or stop needs to be at the nodal point, which for a Petzval is between the two lens elements.

3. There are only two types of Packards; with flash sync and without. There are various sizes. You need one that will fit on or behind your lensboard, but have a large enough opening for the lens you want. Most of the time a petzval is so long you will need to offset either the lens, or the shutter, so there is room betweeen.

Try looking here:
http://www.antiquecameras.net/petzvallens.html

http://creativeimagemaker.co.uk/mod/resource/view.php?id=120 (http://creativeimagemaker.co.uk/mod/resource/view.php?id=120)

Garrett

[Steven Tribe]

Look under " reasonable price petzval lenses " for a current discussion. The photos posted there give some idea of one of the mass produced projection lenses which is available and will cover 4x5. This type, and the one with the sliding front cover talked about there and currently on a well known auction site are petzvals which was the cheapest lens type to produce at the time. These types always seem to be 5cm (2") x 10 - 11 cm and the barrels are threaded quite deep at the back to allow the manufacturer to install lenses of different focal lengths. They are not fast like the "sexy" taking lenses from Voigtländer etc. but speed is not a good thing with modern emulsions and primitive shutters!

[Lachlan 717]

Another (and, in my opinion much better) option to the Packard is a Sinar Auto Aperture Shutter.

This allows most barrel/shutterless lenses to be used without the fiddley Packard air system. You get accurate timing over many shutter speeds (esp long exposures) rather than 1 guessed shutter speed.

And, rather than just using a Sinar rail camera, I have it on expert advice that a wooden field camera will soon be available that accepts these shutters.

Lachlan.

[Mark Sawyer]

1. What are the distinguishing descriptors which would suggest the lens might well have a Petzval formula?

2. From other threads here I learned that often brass Magic Lantern lenses might be suitable, but these typically don't have Waterhouse stops. How do you otherwise create these iris stops. Do they have to be behind the lens or can they also be at the front (easier) but will that somehow affect the image. It seems a shame to cut the barrel to place home made stops between the two lens elements. But I guess that could be done if you are so inclined. Have others done this?

3. I understand that the easiest (but not easy) way to establish a shutter mechanism is to somehow fasten a Packard shutter behind the lensboard. However there seems to be limited information which I have found about these shutters. What type of Packard shutter should I look for.

Thanks for the help..

1.) The Petzval is a specific design, two elements cemented together at the front, and two more separated at the rear. You can identify one by the internal reflection patterns, but if a seller doesn't know lenses, he/she probably won't be able to make a reliable identification.

2.) Magic Lantern and other projection Petzvals tend to be a bit lower quality, but that works well for some people. The Petzval "look" is most visible wide open, so that's where most photographers use them most often. Stopped down, they have a signature more similar to modern lenses, so you might as well just use a modern lens there...

If you don't want to cut the barrel for Waterhouse stops, you might be able to unscrew the front of the lens and slide in a home-made stop. If it's in the wrong place, it will adversely affect the field curvature and coma, but the Petzval has a curved field and coma issues anyways. That's why people use them!

3.) Look for a Packard shutter that works well, is the right size, and can do "instantaneous" exposures. (The #5 only opens and closes manually, the #6 will do that and, with the insertion of a pin, an instant exposure of around 1/25 of a second.