GABOR HOLOGRAM

The great-granddaddy of them all! Not many holograms are made in this configuration, because of two major flaws which will become obvious as you observe the reconstruction of this hologram's image: one, you are looking directly into the reconstructing light source, and secondly, there is the pesky secondary, real image.

So fire up a small laser, expand its beam, and let the reference beam impinge along the normal. Or point a larger laser at white object and use the light scattered from the spot to replay the hologram. It won't be as sharp, but it will be eye safer.

There are two virtual dice, a five and a two for the lucky seven, and if you view the hologram at arm's length or further, you will also observe their real image twins floating in front of the hologram. Looking at a row of street lamps through the hologram will conjure up lots of images of dice!

This batch of holograms was shot on the original Big Beam, (see Seven Single Beam Projects pages) circa 1986 or 87. The image is called Denny's Dice, as I made proof of existence holograms of each of the seven projects using dice, (What else? Skulls? Chessmen?) naming them after the inventor or major practitioner of the technique.

This batch of holograms was shot on the original Big Beam. Here is a shot of one of the two objects on the beam, probably the only picture of this set up. The piece of white paper is the line up for the film; the 70mm Film Transport replaced it for the production run

A Black and White Chemical Photo!

The objects, graphic images of dice, were first laid out on blue line graph paper, and made with Formaline tape. Then the artwork was photographed on the late, great, Kodak Technical Pan film in 35mm size, and blown up on to an Agfa Holotest 8E75HD plate to get the image floating in space.

The image was blown up with my trusty Beseler 23C enlarger. The Holotest plate required a 50" exposure, while exposing onto Agfa Brovira photographic paper required a .5" exposure, showing that the Holotest is about 2 orders of magnitude slower than photographic paper! It was assumed that photgraphic papers had an ASA, excuse me ISO rating of about 1, then the Holotest has an ISO of .01!

The holograms that were shot in the 15 foot Bubble Chamber at FermiLab of physics events were of this simple Gabor type of geometry!

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