T3D Re: Lenticular Prints

[George Gioumousis <georggms@xxxxxxxxxx>]

Dylan The Hippy Wabbit wrote
Can anyone fill me in on how lenticular prints work?  I've got the broad
picture, but I can't find any good information on the details.

I, Dr G, wrote, in answer
The Nimslo prints have lenticules .005 in wide. There are 4 stripes 
(.001 in wide) under each lenticule, one from each lens. The emulsion
is on the back side of the material. The prints are made through the
lenticules, one for each negative, on some pretty precise machinery, 
then a very white coating is applied to the back side of the emulsion.

Dave Spacey, aka Dylan, wrote
Am I right in thinking that implies a 0.001 in unexposed strip?
Presumably that would be under the joint between the lenticules.  If it's
not just a rounding error then it would make a useful alignment guide.
When the white strip disappears the lenticular layer is positioned
correctly.  :-)


Peter Homer <P.J.Homer@xxxxxxxxxxxxx>, wrote
Actualy I believe I read somewhere that the Nimslo prints had a total of
16 stripes under each lenticule because each of the 4 images was printed 4
times with movement in the enlarger between exposures . But that does not
agree with the stripes being .001 in wide and the lenticules .005 in wide.

Greg W. wrote,
That's going to require a minimum 1,000 dpi resolution printer in at
least one axis, and since you can't trade off dots to get more colors
(because that enlarges the effective dot size), it will have to be able
to print continuous-tone ideally (dye-sub for example), or at least
in multiple shades/pixel if you're willing to make that trade-off too
(color banding/false contouring).

While those specs aren't unachievable, they are going to limit the
choices quite a bit.  You could use a lower LPI material to ease these
requirements.

Now back to me, George G.
I must admit it's at least 8 years since I read the Nimslo patents, 
so my memory might be a bit fuzzy. I do remember the numbers .001. .005 
and 4 quite well, and also that there was no point in having a stripe under 
the joint. However, I also remember a patent that ran lots of stripes, but 
I think that was one of the earlier patents.

It takes a lot of things coming out just right to make this work, and
part of the trick is to expose through the lenticules, which more or less
puts the stripes in the right place. As Greg W. said, this would not be
easy with a printer. Clearly he is right that one would have to use a low
LPI material. 

I have read that Kodak makes large lenticular displays, but I've never seen
one. I have seen an 8x10 print a friend had made at Nimslo; looked better
than the tiny prints. I also so a couple of larger than 8x10 lenticular
transparencies at a photo show a while ago. One was of John Wayne with
tobacco smoke (which seems in poor taste) and the other of a young lady
in a skimpy costume.

I would love to see some results using a printer. If anyone gets anywhere,
please let us know.

George G.


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