Movie Cameras

Ultra-16 Viewfinder for 15mm Lens on Bolex

The 15mm lens gives a very pleasant look in the Ultra-16 format.  However  my modified Bolex Octameter Viewfinder I was telling you about last time, only zooms out to 25mm.  So the thought came… why not use that neat little Phago viewfinder that I’ve been using on the GIC camera.  It’s vertical field-of-view is correct for about 15mm on regular-16,  but horizontally it goes out wider,  as it’s  meant for a still camera ratio of 1.5 to 1.  So I reckoned if I added a mask for 1.85 :1  this would be right for U16.  I used a plastic Canon EOS eyecup frame  (lots about !) modified so it slips over the front lens of the Phago finder.  The frame has been filed out to 1.85:1 ratio.  It’s secured by a small bracket over a 2.5mm bolt fixed to the top of the finder. A nut can be added but isn’t that necessary;  I want it reasonably quick to detach for use on the GIC camera which is Regular-16.

Now,  how to attach the viewfinder to the Bolex ?   Luckily I had an old Octameter chassis, and I made use of the panel that fixes to the camera door.  Removed most of the rest.  Then I found an accessory shoe on an old flash bracket,  sawed it off,  and with a small chunk of aluminium it’s  all bolted to the Octameter panel. The Phago’s GIC  bracket slots into the accessory shoe.  No parallax adjustment provided but at least it’s  simple to attach and use.  And the Phago is incredibly bright and clear,  better I have to say than the Bolex Octameter finder.

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  1. Doug,

    Your solution to the 15mm viewfinder problem for Ultra16 looks good!

    What effect does the distance from the film plane have on this viewfinder’s field of view — can this only be determined by using the Bolex CADRO prism focuser?

    Best wishes,

    1. Hello James
      Not sure if you mean the sideways distance ? Or the fact it’s a short distance behind the film plane. It doesn’t seem to have any effect on field-of-view, unless of course the subject is close. And the Bolex CADRO focuser was very handy to compare images. I should also mention that this accessory should be used with great care, so that the glass prism doesn’t scratch the polished surfaces of the gate.
      Thanks !

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