Auxiliary Fisheye Attachment Lenses

Fisheye lenses. Skaters love 'em, people hate 'em. I exaggerate, but I think most photographer's would agree that this unique lens has a time and place. Ever since I got into the world of photography I remember wanting to experiment with a fisheye lens. I liked that it provided a way of seeing I was unaccustomed to. Without the aid of such an optic, I would never be able to experience such a vast field of view, simultaneously. I also realized quickly, that such a unique capability came at a premium.
So if you're looking to buy a fisheye, but cannot bring yourself to drop the serious kind of money it would cost to get one manufactured by the top brands, or you just don't have the cash to begin with, this might be the perfect solution! The catch is, as this fisheye is an "attachment", you need a base lens. Below I will discuss what types of lenses work best (50mm-200mm. most 50mm's work very well and are among the cheapest lenses available). If you do not have any of these lenses, then indeed it may be easier/cheaper to purchase a true fisheye lens.
The solution to which I am refering is called an Auxiliary Fisheye Attachment. These lenses were made, from what I have found, back in the 70's. As in many other cases, only a few variations were manufactured, yet a barrage of names appeared around the ring near the top of the lens. Spiratone, Soligor, Accura, Makinon, Kenko, Panagor, Kalcor, Portertown, and Samigon are all I have come across thus far, but I am sure there are more. Peter Ganzel's site has an entire page dedicated to these units. Below, I have compiled a few examples from his site as well as a couple I took.
HOW IT ATTACHES
I have owned 3 versions of these units. Each was different! To the right, I have created a visual to demonstrate the basic components. They are as follows (from top to bottom):
1. Lens cap
2. Lens unit
3. Adapter Ring
4. Step Ring
5. Base Lens

The lower part of the lens unit (which has a large silver screw) also detaches but I am unsure exactly why this is. Ideally, the lens attaches to the front of a base lens via the filter thread. Depending perhaps on who made it and when, the adapter rings size is varied. Of the samples I have had, the adapter rings could be swapped to mount on any brand aux fisheye so it would seem the very small thread which connects the adapter to the lens unit might be universal among these fisheyes, but I cannot say for sure. In any case, the adapter rings vary in size on the filter side for sure. I have had a 52mm, 55mm, as well as a Series VII. Consequently, the next part of the assembly is a step ring. The size is completely dependent on your specific adapter ring size and the lens on which you wish to mount the fisheye. And the lens makes all the difference in the world.So let's talk about choosing a lens. Each fisheye I have seen has a ring denoting various focal lengths. According the the directions for use, the user is to set this ring to the appropriate focal length lens. The focal lengths listed are typically between 45-200mm. Different focal length lenses will yield very different results. For the samples at the end of this post, I used a Nikon D200 with a 1.5x crop factor senor and a Nikon 50mm f1.8 Series E lens as my base unit. However, when I put the same lens assembly on my D700, because of the full frame sensor, I can see the whole circular image and there is much more negative space. Consequently, I tried the attachment on a Nikon 105mm f4 Micro lens. This yielded something much closer to a full frame fisheye, in which almost the entirety of the sensor was being used. So it really comes down to experimentation! Here are some things to consider:
- Faster is better. These attachments will take the lens down a couple stops. Starting with an f/5.6 is not only going to make composition and hand held shots tough, it will most likely yield poor results. Preferably something f2.8 or faster.

- Prominent front elements. It seems the nearer the optics of the base lens are to the attachment, the better. Some lenses, such as the Nikon AF 50mm have a recessed front element and in my experience, will actually hinder the functionality of the fisheye.

- Heavy! These attachments are from the 70's. They are well-built with all metal constructions. Be sure to choose a lens with a durable front ring that can support the weight. Plastic lenses will struggle with these. I give the plastic Nikon 35-70mm f3.3-whatever a go. The rig sounded awful.
HOW IT WORKS

Simple, they used to have directions posted on the inside of the lens cap (image courtesy of Peter Ganzel)!




Now, in all honesty, these will not yield the edge-to-edge sharp images of a Nikkor lens. They won't necessarily prove convenient either. What they WILL do is give a true fisheye image. And with some ingenuity, prove a very versatile tool. These can be used on a number of cameras including medium format!
Here a just a few samples of some things I have done with these lenses. All were shot with the Nikon 50mm as the base lens on a Nikon D200. I also engineered a ringflash to accompany the fisheye for the portraits.

KEEP IT GOIN' KEEP IT GOIN' KEEP IT GOIN' FULL STEAM...

This guy took one of these fisheyes bungee jumping as an inexpensive alternative to a more costly lens. I'm thinkin however, if something went wrong the broken lens would be the least of his problems...

As previously stated, Peter Ganzel has a webpage with more examples of these fisheye converters.

I found a thread on photo.net in which members discussed these fisheye things a bit.

Fantastic! Scan of original user manual for the Spiratone Auxiliary Fisheye: http://www.apecity.com/manuals/pdf/spiratone_fisheye_auxiliary_lens.pdf

This page has more information and some neat original advertisements: http://www.thecuckoofarm.com/cuckoo/photo/lens/lensacc/spirfisheye/spirfisheye.php