Minas Tirith

I’ve been working on a commission from a co-worker for a bit now and the last few days have been spent doing tests (I generally manage to get one in a day during the week) of new bleaches and color swelling.

[originally posted Apr 6, 2005]

[edited Apr 8 to add green version]

The original model was lit a bit hot on the left hand side and with the JD2 bleach that side was coming out a shorter wavelength (more green) than the rest. Yesterday I started using EDTA bleach and the results have been striking.

The hologram above was made yesterday with untreated PFG-01 and shot with a 25mW HeNe for 30 seconds and developed for 50 seconds. It’s a nice clear deep red and due to the brightness, very hard to photograph with my digital camera.

The picture above is actually of two holograms. Last night I cut two strips from a full-size sheet of film and soaked the one on the right in 1.25% TEA and the one on the left in 3.75% TEA. This morning I took the two strips, put them side by side in the film holder and exposed for 30 seconds. It doesn’t show well in the picture (the holograms are so bright that I had to stop the camera aperture way down which affected its color response) but the one on the left is actually yellow with a tinge of green while the one on the right is more orange.

Vital Statistics:
H2 on PFG-01 film exposed HeNe for 30 seconds.
Developed 50 seconds in JD2, bleached with EDTA
Post bleach Ascorbic acid bath.
No TEA on first picture, 1.25 & 3.75% on second (right to left).

Here’s the latest green shot. It was pre-swelled with 5% TEA and exposed for 15 seconds, developed 30 seconds in D-19 and bleached in EDTA.

And just for grins, here’s the green shot next to a DCG from the last PCG Gathering.

Here’s also a newer shot of a version on un-treated PFG-01.

If you’d like to buy a copy of this 5×7" hologram, click here.

Author: Michael Harrison

Husband, Programmer, Irish dancer, tinkerer, astronomer, layabout (as much as possible)

One thought on “Minas Tirith”

  1. Anyone have any foolproof methods for index matching sheets of PFG-01 roll film to glass? For 4×5″ sheets I’d used both mineral oil and lamp oil with decent success, although I detest the messiness of it.
    I’ve been working on the final Minas Tirith holo

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