My Super Wide Angle Stereo Camera Rig

I have never been a big fan of wide angle stereo photography, let alone super wide. But recently I have assembled a super wide angle stereo camera, based on Voigtländer equipment and I am experimenting with interesting results.

Voigtländer

Here is some information about the company (source: Wikipedia, http://en.wikipedia.org/wiki/Voigtlander).

Voigtländer is an optical company founded by Johann Christoph Voigtländer in Vienna in 1756 and thus it is one of the oldest names in camera equipment. Some of its famous products through the years include the Petzval photographic lens (fastest lens at that time: f/3.7) in 1840, the world's first all-metal daguerrotype camera (Ganzmetallkamera) in 1841, the first zoom lens (36–82/2.8 Zoomar) in 1960 and the first 35mm camera with built-in electronic flash (Vitrona) in 1965.

The company sold its shares to the Carl Zeiss Foundation in 1956, and Zeiss and Voigtländer integrated in 1965. In 1972 Zeiss/Voigtländer stopped producing cameras, and a year later Zeiss sold Voigtländer to Rollei. In the late 1990s, Cosina licensed the rights to use the Voigtländer name, and the names of Voigtländer lenses, for its own products. So since 1999 all Voigtländer products are made by Cosina.

The company’s current products are listed in http://www.voigtlaender.com/ and include rangefinder cameras and lenses with Leica screwmount and bayonet mounts. As you can see, if you visit their products page, the majority of their lenses are in the wide/super wide range. This is expected because rangefinder cameras are well suited for this kind of photography.



My RBT/Voigtländer 3D Rig

My super wide angle stereo camera rig consists of an RBT S2 Stereo camera (see:
http://www.rbt-3d.de/index.php?client=1&lang=4&idcat=64&idart=57) and a pair of 15 mm Super Wide Heliar lenses.

The RBT S2 stereo camera is based on the Voigtländer Bessa R2 camera and has the following features:
• Leica M-mount
• Manual operation (no batteries required)
• Through the lens light metering
• Twin VF, bubble level, Self timer
• 75mm lens spacing (other configurations are available too)

The 15 mm Super Wide Heliar is a newer lens by Voigtländer. It comes with a Leica-M mount and it is extremely compact (one of the advantages of RF lens design is that the lens can go back into the camera and does not need to clear a mirror as it is the case with SLR cameras). Other features:
• Aperture range f4.5-f22 with ½ stops
• 6 groups, 8 elements, 110˚ angle
• Diameter: 59mm, Length: 38mm
• Weight: 156g (5.5 oz!)
• Filter mount: 52mm
• Integrated Lenshood

Another necessary ingredient for the system to work is a separate 15mm view-finder. Shown in the pictures here is also an external light meter (Voigtländer VC meter) mounted at the top. This is not necessary but allows me to set the exposure by looking at the top, instead of through the camera’s view-finder. Also, for my camera I have an original Voigtländer strap and camera grip. I bought the RBT camera from 3D Concepts (www.stereoscopy.com/3d-concepts/) and lenses & accessories from http://www.cameraquest.com/

Ultra-wide angle photography is a specialized area and I am still experimenting and learning what works and what does not work. Expect to see some examples in our next stereo club soon.

RBT Film Formats

To understand the dilemma that RBT (or any person/company attempting to design a 35mm stereo camera) faces, consider the size of the full-frame 35mm film format: 24x36mm. The simplest solution for film economy, while maintaining full frame, is to have a full frame pair, separated by a full frame. This design will lead to the sequence: ABAB/CDCD/, etc. (the film can be cut every two pairs without splitting a pair) The only problem is that the minimum separation of a pair is 2 x 36mm = 72mm. That would have been the case if the pictures touched each other. With a bit of a margin between each pair, we arrive to the 75mm image (and lens) separation

This is configuration B, possibly the most popular configuration. The configuration leads to alternating advance sequence (1-3-1-3, etc). One advantage is that the roll looks similar to a standard roll exposed from a 2d camera, so the slides can be handled and mounted by automated machines. The disadvantage is that the lens spacing (75mm) is wider than the spacing of the eyes (which is around 65mm average).

If one does not like this 75mm wide separation of the lenses (dictated by the separation of the images on the film) then they have two options:

1) Reduce the image size. Keep the same basic format (ABAB/CDCD/, etc, alternating advance sequence) but make the size of each picture slightly smaller, 33mm instead of 36mm. By cutting 3mm from each picture, we can reduce the spacing of the images and lenses by about 9mm. The result is a 65mm lens spacing (desirable) but the image size is smaller and the roll cannot be processed by automated machines. This is configuration A.

2) Leave a gap between each pair (i.e. have no images recorded between two pairs). In this case we can keep any spacing of images (and lenses) at the expense of film economy. This is configuration C. This configuration only gives 13 pairs per 36 exp roll (vs. 20 for configuration A).



Which format is best?

It depends. Three questions to ask: 1) Is orthostereo (65mm) important to you? 2) Is automated processing important to you? 3) Is having full frame images (36mm wide) important to you?

Format B gives up orthostereo for automatic processing. If you want automatic processing, then B is the only choice, at the expense of orthostereo. If you want orthostereo but don’t care for automatic processing (because you are doing your own stereo slide mounting, for example) then go for A (film economy) or C (full frame size).

How important is the difference between 65mm and 75mm?

Some people will say that this difference is small. Some people will actually prefer the extra “depth boost” of the 75mm spacing. Those coming from the Stereo Realist format (70mm) should have no problem adjusting to 75mm. But, for me, coming from the gentle depth of the RBT S1 (59mm), the 75mm is too much. I do not like indoor shots taken with 75mm lens spacing. So I want 65mm. I also don’t care for full frame and I prefer film economy. The format of choice for me is A.

The RBT S1 camera follows a different format. For some reason, RBT designed the RBT S1 with a 59mm spacing. This leads to exactly half frame gap between each stereo pair. The film advance is fixed (20 perforations). Maybe this choice was dictated by the details of the film advance modification when joining the cameras. The RBT S1b uses a 45mm lens spacing but apparently the same advance sequence (and film waste) as the S1. This reinforces the idea that the details of the camera advance modification have led to this unsual format. I’ve heard that the RBT S1b was made especially for underwater stereo photography. Some people think that the 59mm spacing of lenses in the S1 is already too small, but personally I have grown accustomed to it.

RBT Stereo Cameras

The RBT Company in Germany has been joining 2d cameras to create 3d stereo cameras for quite a few years now. They probably started inspired by the work of Fritz Ochotta, linking Yashica cameras. Their web site is: http://www.rbt-3d.de/. The importer of RBT products in the USA is 3D Concepts: www.stereoscopy.com/3d-concepts/. Here is a list of the RBT cameras I am aware of:

A. RBT SLR cameras – Usually prefixed by “X”

RBT 108: Yashica 108 bodies, Yashica/Contax (Y/C) mount
RBT 109: Yashica 109 bodies, Y/C mount
RBT X2 – Ricoh KR 10M bodies, Pentax K mount
RBT X2II: Ricoh XR-X3000 bodies, Pentax K mount
RBT X3 – Ricoh XR-X3PF bodies, Pentax K mount
RBT X4 – Cosina Cs1 bodies, Pentax K mount
RBT X5 – Cosina FM10 bodies, Nikon F mount

B. RBT Rangefinder cameras – Prefixed by “S”

RBT S1 – Konica Hexar bodies, fixed 35mm f2.0 lenses, 59mm lens spacing
RBT S1b – Like above with only 45m spacing of lenses
RBT S2 - Voigtlander Bessa R2 bodies, Leica M mount
RBT S2a - Voigtlander Bessa R2a bodies, Leica M mount
RBT S2b - Voigtlander Bessa R2b bodies, Leica M mount
RBT S3a – Voigtlander Bessa R3a bodies, Leica M mount
RBT S3 – Zeiss Icon bodies, Leica M mount

From what I gather from the RBT web site, only the 109, X2II, X4, X5 and S2, S2b, S3, are currently produced. The 3d-Concepts web site lists as S3 a Voigtlander camera with Bessa R3 bodies. I am calling S3 the Zeiss Icon camera, following the RBT web site.

Most RBT cameras come in one of three configurations: A, B, C. More about these configurations in the following blog.

I have personally owned the following cameras: 108, X2II, X3, X4, S1, and now S3. The RBT S1 remains my favorite stereo camera.

Ochotta Stereo Camera - How it all started

It all started last December when I saw an auction in ebay with the strange title: “Stereo Reflex Camera, Manifacturer Ochota”.

The pictures showed a stereo camera that looked very similar to an RBT SLR type camera, but it was not made by RBT. I was intrigued and attracted to this camera and the two coupled Carl Zeiss Contax lenses (Distagon 35mm f2.8) but I did not need another stereo camera so I let it go. The opening bid was $2,500 and the auction closed without any bids.

A few days later, at a moment of weakness, I emailed the seller to ask if they would accept an offer. The seller (Sissi Stanek, well known stereo photographer, see her web page: www.stanek.name/) accepted the offer and so in late December I became the proud owner of this camera.

That was the beginning of a new obsession for me. In a very short time I have learned quite a bit regarding the Yashica/Contax SLR cameras, and the German genius who built stereo cameras out of them.