Twin Cameras

[Mark_Poole@xxxxxxxxxxxxxxxxxxxx (Mark Poole)]

     First:
     Thanks to everyone who went to the trouble of explaining the Keystone 
     effect.  I now have a much better understanding.
     
     Second:  I am in need of good Postscript software.  I am unable to 
     view the documentation alluded to.  I have tried Adobe Acrobat, but I 
     have had difficulties with it (all the graphics drop out).
     Any suggestions?
     
     Third: On Sat, 9 Dec 1995 Thomas Lang asked about Twin camera rigs vs
     Stereo Realist.
     I have only Twin Camera experience, so I can only comment about that.
     
     Cheap shutter synch: I have seen some posts about taking two 
     electronic wire models and splicing them in together.
     I have not done this.
     
     Expensive shutter synch: Wireless models with a master trigger and two 
     slaves.  These were created for wildlife photography and you can 
     trigger them from 20 -30 yards away.  About $300.  I love mine.  The 
     main drawback is that the unit will not trigger the autofocus.  You 
     must preset this.  This setup works well.  I have had few problems 
     with it.  The only time it messed up was when I was on top of Flat Top 
     Mountain (Bedford, VA) on a very foggy (or low-flying clouds) day.
     The wind was stiff and I guess the moisture in the cold air would 
     prevent the infrared light from reaching the slave units at the same 
     time.  One would fire, the other would not.  
     As I have said before, the real novelty is that I can now be in the 
     picture, too.
     
     When I first started, I got a pair of cheap aluminum camera mounts 
     ($3) and screwed them to a piece of 3/4" plywood, and mounted the 
     cameras bottom to bottom. I worked at a woodworking supply house, so, 
     I got a 1/4" x 20 steel threaded insert and screwed this into the 
     plywood.  This is the correct size for photo hardware.  I attached 
     this to my tripod and flipped the head 90 degrees.  This worked really 
     good, and looked like hell.  The images came out great.
     
     I wanted to mess with hyperstereo, so I built a really ugly slide bar 
     out of an old storm door.  It had a lot of play in it, owing to its 
     quick creation, but it produced some nice images.  I have just 
     completed the next iteration in this do-it-yourself exploration.  I am 
     composing my notes and will post the details of this later.  I have 
     seen some nice hyper bars for around $170 in NSA Stereo World.
     
     I shoot slides.  I haven't tried prints.  I started shooting with 
     Kodak, then switched to Seattle Film Works brand to save money.
     I am switching back to Kodak, or may try Fuji.  The SFW film just 
     looks too washed out and grainy. To view these I use the Franka from 
     Reel 3D, but others have suggested models with an internal light 
     source.  I think I will try one of these.
     
     Some quick observations on Twin SLR Cameras:
     Pros:
     Interchangeable lenses.
     Great images from using good optics.
     Can get slides processed anywhere, and just drop them in the viewer 
     with no cutting or mounting.
     Great flexibility with Hyperstereo.
     
     Cons:
     Must be very careful with both camera settings (I set aperture 
     priority, shutter speed usually doesn't play as big a role as 
     depth-of-field).
     This rig is big and heavy.  I have never attempted to freehand it, and 
     probably couldn't without assistance.  Just getting it out of the car 
     is a production.
     Lack of spontaneity, due to fiddling with this and that, setting up 
     tripod, assuring everything is level, the cameras have the correct 
     orientation, all slaves and master set on and set up to same channel, 
     etc., etc.
     Shutter synch difficulties.
     Flash synch difficulties.
     
     Summary:
     I like my twin rig, probably because I have suffered so much to get it 
     right.  I would like a smaller, lighter and more spontaneous option, 
     with a normal interoccular distance, for indoors, in tight spaces.
     
     You get attention with the kind of set up I have.  I spend much time 
     explaining stereo, and finally I started carrying around a cheapie 
     viewer with a slide-pair in it.  Most people get really excited by it, 
     and I make a lot of new friends.  Hopefully I get people interested in 
     stereo.  I have run into a few people who say, "I used to do that, I 
     even have an old xxxx camera, but haven't touched it in years."  Most 
     of these guys have kids in tow, and as they walk off I can almost read 
     their thoughts; "Well, maybe I should dust that sucker off and..."
     
     One last note:  I was at the Ashville (NC) zoo, in the big African cat 
     area.  A Chervil or Civet (I forget which) had been ignoring all the 
     other shutterbugs.  When she turned and spied my setup her ears went 
     back and she let out what my wife later called the "hiss-from-hell."  
     I guess the twin camera lenses looked like the eyes of a big predator 
     (Either that or she just didn't like my face).  I was so startled that 
     I didn't get the shot. Oh, well...
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     Mark Poole               |  Mark_Poole@xxxxxxxxxxxxxxxxxxxx 
     The ants find kingdoms in a foot of ground -William Rose Benet 
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