This is a modification of the two beam transmission layout. (So go read that first... :-)

Deltas from the last run:

The variable beam splitter is a pain. I probably do not have enough light, but I was unable to find a position which resulted in the beams being balanced. The beam splitter was all the way at one end of its travel. It also does absolutely horrible things to the beam quality (multiple reflections interfering with each other). I have attempted to address that by putting some glass on the beam splitter, as well as trying to build a spatial filter. (pin holes are a pain, the spatial filter will be a separate web page eventually...)

In this layout, the reference beam is the one going straight through the beam splitter, since the reflected one seems to get drooled on the most.

Hologram 10.1: (star)
reference beam is 0.12 micro-watts, object beam is 0.14 micro-watts. The resulting exposure is 384 seconds, but is cut short by passing motorcycles. (This is memorial day weekend, and I'm right outside Washington DC, so components of the Rolling Thunder motorcycle ride were rumbling around.)

Developed for 6 minutes. Turned out OK... Reconstructs red/orange.

Hologram 10.2: (star)
same as 10.1, only got the entire 384 second exposure. Turned out remarkably like 10.1, even though its twice the exposure. Got some film movement which resulted in a really bizzare bulls-eye shaped pattern which moved as the angle of the reconstruction light changed.

It also got a rather impressive transmission hologram, from light reflecting in through the edge of the glass the film was sandwiched between. Reconstructs red/yellow/green, as the illumination light changes angles.

Hologram 10.3: (star)
Grossly under-exposed, operator error on the light meter.

Hologram 10.4: (foo dog)
Object is 0.16 micro-watts, reference is 0.12 micro-watts, 240 second exposure.

Developed 4 minutes (it seemed dense enough...). Did not come out, due to film motion. (Big blob right in the middle of the image) reconstructs orangeish.

Successful things: