Petzval 85mm and 58mm lenses are two focal lengths available presently and both of them are characterized by their immensely swirly bokeh, strong field curvature, and sharp central focus. For lomography lovers and for photographers who long for something different, these happen to be a very attractive lenses.
(Petzval 85mm f/2.2 lenses, in golden and black colors)
History of Petzval
In the beginning days of its photography, the lenses that were used were very slow and required long exposures. They were based around the camera obscura after all. Josef Max Petzval, a mathematician, understood this problem and developed a lens design which was comparatively fast and not too big. He gave this design to Peter von Voigtlander, who was in the business of making lenses and telescopes. I841, Voigtlander and Son, launched the first camera with the lens based on Petzval design. This was a camera with a very sharp and fast lens for its time. The whole set was made in brass and shipped disassembled in an elegant wooden case. Considering the history of Voigtlander and Son, it was no surprise that the final camera with the Petzval lens looked like a telescope. It used round sensitized plate for capturing the photograph.
For many decades, Petzval design was used by various manufacturers with slight alterations, on different types of cameras, including some of the large format cameras as well. Some people also say that many of the present day prime lenses with simple designs are still based on this but with refinements.
Lomography New Petzval 85 Art Lens
Well, the lens is no longer new and definitely no longer limited to lomography enthusiasts. This was the first in the series of Petzval lenses that was released by KMZ factory (which also used to manufacture Zenit cameras). The company touts the lens as sharp in the center with strong color saturation and swirly bokeh. Unlike standard lenses, the company also proudly acknowledges the vignetting. 85mm focal length is well suited for portraits.
Petzval 58mm f/1.9 Bokeh Control Art Lens
The latest version, Petzval 58mm f/1.9 Bokeh Control Art Lens is designed to be used with present day cameras and still give the look of the first Petzval lens from 1841. The 58mm focal length is well suited for APS-C sized sensor cameras. The lens has a unique Bokeh Control Ring on-top of the lens to adjust the bokeh intensity within a 7 levels range. Lens uses a manual geared rack focus system. The lens uses interchangeable diaphragms which slide into the lens. These diaphragms have varying sizes and act as aperture control. These waterhouse stops provide a range from f/1.9 to f/16. As with regular apertures, the depth of field also varies with the ‘stop’ used. The widest stop which allows the maximum light (f/1.9) provides the best bokeh effects.
(Notice the swirly bokeh, a hallmark of Petzval lenses)
Here are some other options for those of you who want such swirly bokeh effects but can’t afford the lens or justify its price –
A jagged edged mask over the front element. This is the simplest option. Use a dark paper and cut an oval hole in it with jagged edges. The hole should be large enough to allow at least center half of the front element to be visible. Attach the dark paper on the front of your 50mm lens so that all the edges are nicely covered and hole falls in the center. Click a few photographs with the aperture wide open (f/1.8 in most inexpensive 50mm lenses). If the vignetting is a problem (if the corners appear very dark), increase the size of the hole a little.
Image-editing on computer. Similar effect can also be added during post-processing / image editing, using a vignette blur tool and a swirl brush. Regardless of what the supporters of Petzval lenses say, the same effects can be easily replicated on the computer, especially if combined with the mask as described above.
I got an opportunity to try out the Petzval 85mm f.2.2 lens. The glossy brass finish and metallic body looks real classy. The lens when attached to a modern DSLR looks eye catching and somewhat weird. To me the optical quality was average and the lens delivered what it was supposed to. The point where I had focused had just acceptable sharpness. The swirly bokeh did look interesting. It gets quite monotonous after sometime. I would rather use this money for something else and try the other methods available to achieve such bokeh. If anyone gifts me this lens, then trust me, I’ll be a really happy person. The lens is really nice but it just is not my kind of thing. (I just hope that the person who had loaned me his beloved Petzval doesn’t read this article.)
When it comes to these lenses, the 85mm focal length is something that would suit me more than the 58mm (though I am planning to buy a sharp 58mm prime too in future). So, I end this short article with the hope that someone will someday gift me a Petzval lens, which I’ll surely enjoy.
Petzval sample image of the girl with swirly bokeh – by Kevin Law / Flickr Creative Commons / CC BY 2.0