Sunday, February 28, 2010

Stereo Realist Panoramic Conversion by Gene F Rhodes



 I remember this '625eq' camera while browsing the links in Robert Monaghan's site long time ago. Recently I rediscovered the same while I again started browsing  Robert's archived site. 

The camera was handmade by Gene F Rhodes well known for his  website photoprojects.net. Though the original website is now defunct, you can retrieve a good amount of information from the archived website available here.

This 35mm converted stereo camera is known as '625eq' because it offers the same aspect ratio what a 6x25 medium format panoramic could provide. The description as I copied exactly from his website is as follows: 
A hand built, fixed lens,  35 mm wide-angle / wide-image panoramic camera made from a damaged Stereo Realist camera body and a  47 mm  f8  view camera lens.  If this were a medium format camera it would be 6 x 25 cm. The Realist's frame and film advance gearing were rebuilt to accommodate a new enlarged 24 x 102 mm image frame.  Three scans are required to load each 102 mm negative into the computer. According to Ron Leven of Schneider Optical the 47 mm  f8 super angulon lens has an image circle of 113 mm at  f11, and a 40.5 mm  filter thread. After many light drop-off tests I find this lens to be unusable without some kind of center filtering, and B&H Photo accepted a  special order for a Heliopan center filter, but they never delivered. This project was my most interesting, but it is now terminated


 This is so far the most detailed description I found about  the panoramic conversion of a stereocamera:
Job 1--Film Advance:    In a Stereo Realist the film take-up spool pulls the film through the camera. The film drives a star wheel sprocket which is shaft connected to a slotted disk cam in the upper chamber.  A cam follower rides on the edge of the disk and is shaft linked to a spring coil brake around the shaft of the take-up spool. When the follower drops into the slot the brake is applied and the film stops. A reset pushbutton moves the cam follower out of the slot, releases the brake and allows the film to be advanced. For stereo format the star wheel makes one turn per exposure but in the new camera the star wheel makes 2.2 turns. The first job was to separate the star wheel and cam with gears to get the 2.2 :1 ratio. The star wheel bearing support was in the image area of the new camera and had to be removed and a new bracket had to be created to support the star wheel, gears and a new cam disk. This required the cam follower to be modified to align properly with the relocated cam. (The gears and bearings were scrounged from my junk box as was the items below.)

Job 2--Lens Mount:      I didn't want to do any unnecessary machining so I decided to use a screw thread focusing technique much like screwing a lid on a jar. In this case the jar is from a pressure transducer bought at an aircraft surplus store and a matching 55 mm threaded lid. The lens is mounted through the lid creating an assembly that is compact and easily removed. The jar was shortened and modified so the front cover could clamp it to the camera. The lens mount was something to be proud of until I discovered severe light leaks. Now it is light tight but kludged.

Job 3--Center Filter: The light drop off at the ends of my negatives is 2-3 stops, and none of my many hand made filters were usable.  I have been using Picture Publisher software to correct the light drop off by using a especially created filter mask. This was satisfactory for a time, but is not a permanent solution.  (See above photos for before/after comparison.)

Job 4--Focus Calibration:   1/8 turn = 20',   1/4 turn = 10',   1/2 turn = 7',   3/4 turn = 6',  1 turn = 5',    2 turns = 3',    4 turns = 2',   9 turns = 1'   and 12 turns = lens fall off.

Note:  The viewer lens is from a one shot Kodak pan camera, but it brackets the image and shows the horizon. When in doubt, I use the yellow bubble balance.

You can visit this page for the description.

The bottom  picture compares the film sizes obtainable by this camera with others.

I thank Mr. Rhodes very much for providing the picture and information on his great handmade panoramic camera.

A handmade 6x17


This is a nice 6x17 by Stefan Lindgren. The camera is constructed of aircraft grade aluminium and equipped with a 90mm large format lens. Quite some technical points are well discussed and illustrated viz. how to make the panoramic  viewfinder , pressure plate etc. I beleive most panoramic camera making aspirants will be benefitted from these guidelines. 

The details are available here:

Visit his web page for more DIY projects along with other related stuff.

http://www.stockholmviews.com/

Another 6x12 by Jack Tait


This is another jewel of Jack Tait's creation. Crafted out of mahogany wood , this has a rotating lens panel providing rise,fall or cross front. The camera was bought by an UK based photographer.

To know more about Jack Tait visit his website:

http://web.me.com/jacktait/Taitographs2/Home.html 

Saturday, February 27, 2010

Some more handmade panoramic cameras

Looks like this  website is related to Horsley Camera, UK well known for their Wideboy and other panoramic cmaeras. The website provides extra information on a shift pinhole and a stereo panoramic camera.

I also found a piece of instructional matter for how to make a DIY motorised 35mm rotational panoramic camera by Mike Rignall here

See my earlier post on Horsley cameras. 

I found a couple of example photos taken by Mike Rignall using his rotational camere in Photosig

Wednesday, February 24, 2010

Master cameramaker Jack Tait and his handmade 6x12


I first saw a pic of this camera in Lee Frost's well known book 'Panoramic Photography' about five years ago. Recently while re-reading the same book, my interest in this camera got rekindled and thanks to Matt Sampson, who told me about the person behind this camera.

Mr. Jack Tait constructed a number of beautiful precision cameras including this one and all were sold away. Besides building cameras he  established  two schools of photography, one of design, written a few books and practiced as a freelance. Being a lover of analog gadgets I very much liked his hand built analog plotting devices or Taitographs: a discipline important enough to be the topic of someone's PhD thesis.

This 6x12 panoramic camera comes with a rising front and shifting viewfinder., making it very suitable for architectural panorama. In his own words, "This was made using a Mamyia 6x12 back and to my knowledge was the first  6x12 camera to have  movable rising front with a fully tracking viewfinder."

I thank Mr. Tait for providing information and pictures of  many  of his handmade cameras which I'll be publishing serially in my blog.

His website being:
Do visit his website to know more about him, his cameras and other very interesting objects.

A digital panoramic by Walter Dubronner


This is again from the collection of Mr. Walter Dubronner. This strange looking camera can be considered as a camera manifold comprised of five cameras. 

The cameras are all interlinked and they take five pictures  simultaneously.Followed by digital stitching to make the final panorama. The only negative point is the high battery consumption.

This semi-circular crown like camera reminds me of a tiara and I named it 'Tiarama' :-)

I thank Mr. Dubronner for providing me the pics. and information about this camera. His other handmade panoramic cameras can be seen here and here.

 

Thursday, February 18, 2010

A Mamiya based 6x12 found in Ebay

Recently this 6x12 panoramic camera got sold in Ebay. The camera had a Super Angulon and a Mamiya roll film back.

Thanks to the seller who kindly allowed me to use the pictures.Thanks are also due to Olaf Matthes who brought this to my notice.