P3D Lens choice for Fader Projectors

[Jon Golden <3dman@xxxxxxxxxxx>]

I have had several requests about choosing lenses for the optimum image
size at the screen..but I thought that this might be good information
for anyone also using Kodak projector lenses of the sizes below, which
we offer with the Brackett Fader or Dissolver.  Image height is recorded
here, so Realist format users can basically figure a square format
image.  European, wide and full format images you can calculate based on
the ratio of your images width to its height.

The following will help you to determine what the vertical height of
your image will be, at a given distance with the optical lengths listed
below.  Lenses listed are based on Kodak models.

New Brackett Fader Projection System, just click on the
link below and scroll down below the RBT 101 projector to see it, but
contact me for more current info and updates!

http://stereoscopy.com/3d-concepts/projector.html

Lens options are priced per pair: Kodak pairs have been carefully
matched for focal length by Bob Brackett, and modified to adapt to the
Fader projector.

$ 210.00 pr   f2.8 85mm
$ 198.00 pr   f2.8 100mm (only focal length matching required)
$ 340.00 pr   f3.5 180mm
$ 360.00 pr   f3.5 70-120mm Zooms
$ 32.00  Special synch cable: adapts two Faders for stereo-dissolve      



IMAGE SIZE: BASED ON OPTICAL LENGTH AND DISTANCE FROM SCREEN

70-120mm Zoom sets: To be determined by user, using guidlines below.

70mm lens
10 ft distance from screen: 34in 
15 ft distance from screen: 60in
20 ft distance from screen: 79in
25 ft distance from screen: 99in
30 ft distance from screen:121in
40 ft distance from screen:160in
50 ft distance from screen:200in
60 ft distance from screen: --
75 ft distance from screen: --
100ft distance from screen: --


75mm lens
10 ft distance from screen: 32 in
15 ft distance from screen: 54in
20 ft distance from screen: 72in
25 ft distance from screen: 90in
30 ft distance from screen:109in
40 ft distance from screen:145in
50 ft distance from screen:181in
60 ft distance from screen: --
75 ft distance from screen: --
100ft distance from screen: --


85mm lens
10 ft distance from screen: 30in
15 ft distance from screen: 49in
20 ft distance from screen: 65in
25 ft distance from screen: 81in
30 ft distance from screen: 97in
40 ft distance from screen:130in
50 ft distance from screen:162in
60 ft distance from screen: --
75 ft distance from screen: --
100ft distance from screen: --

102mm lens
10 ft distance from screen: 27in
15 ft distance from screen: 41in
20 ft distance from screen: 54in
25 ft distance from screen: 68in
30 ft distance from screen: 82in
40 ft distance from screen: 109in
50 ft distance from screen: 136in
60 ft distance from screen: 163in
75 ft distance from screen: --
100ft distance from screen: --

120mm lens
10 ft distance from screen: 23in
15 ft distance from screen: 34in
20 ft distance from screen: 46in
25 ft distance from screen: 57in
30 ft distance from screen: 68in
40 ft distance from screen: 91in
50 ft distance from screen:114in 
60 ft distance from screen:137in
75 ft distance from screen:171in
100ft distance from screen: --

180mm lens
10 ft distance from screen: 16in
15 ft distance from screen: 23in
20 ft distance from screen: 31in
25 ft distance from screen: 39in
30 ft distance from screen: 47in
40 ft distance from screen: 62in
50 ft distance from screen: 78in
60 ft distance from screen: 98in
75 ft distance from screen:117in
100ft distance from screen:156in

If you have any further questions, please do not hesitate to ask.
        
Regar-D-D-D-s Jon Golden

3D Concepts
P.O. Box 205 
Waban, MA 02468
3dman@xxxxxxxxxxx 
http://www.stereoscopy.com/3d-concepts
Tel: 617-332-5460


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