First, to put things into context. It was always a source of frustration
that one was not able to manipulate colour transparancies in the same
way that black and white negatives could be manipulated in the darkroom.
(Amateur colour printing had not yet arrived). So, when I had set up my
digital darkroom I decided to investigate copying and manipulating some
of my old colour slides. After studying the literature, I decided to
make copies using my Olympus SP-500 UZ with an adjustable close-up
attachment with supplementary lenses attached to the front of the
camera. Images were recorded in both RAW and JPEG.
Images for this exercise were selected, more or less at random, from
those which had been made from Kodachrome 25 colour transparencies
which were about 30 years old. Only JPEG images as produced by the
camera were used and no attempt has been made to produce the correct,
restored image but rather to be able to compare the results obtained
from the two extremes of the slider setting and the original copy. Also,
as this was not a debuging exercise, no reference has been made to any
images which caused error messages to be displayed. The settings were
'Make less blue' -> Yes, 'Combine all layers' -> Yes and 'Degree of
Restoration' slider settings were either 1.2 or 0.7.
The images are available at www.littletank.org/upload and are arranged
in groups of 3. The left-hand image is the original slide copy, the
centre image is with the slider set at 1.2 and the right-hand image is
with the slider set to 0.7. You are free to use these images for any
tests, measurements or observations you care to make and if you have any
questions please do not hesitate to ask. All I ask is that if you want
to use any of them in any publication, please let me know.
So far, the process looks very encouraging but there must be many
questions to be answered before it will be possible to comment with
confidence on the use of the Restore plug-in. For example, what effect,
if any, is there on the fine detail stored within the original
I hope that these observations and the images will prove to be useful.
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