Kodak Retires Kodachrome Film

[Photo Engineer]

Wow, that _is_ a fascinating process! Thanks for the image. If you are able to disclose, to what level of machining tolerance do those ladders have to made in order to assure accurate emulsion thickness across 42 inches?

Laser cut Joblock (sp?) tolerances are used to make the device. They are constantly aligned to maintain the exact nature of the hopper and they are made of Titanium for strength and corrosion resistance.

PE

[Photo Engineer]

Laminar Flow or: How I Learned To Stop Worrying and Love Fluid Dynamics.

More than that is involved including viscosity, surfactant and content.

In fact, the measure for viscosity or even better the coatability, Poise or Centipoise, are not fine enough for this work. Kodak engineers devised a new methodology and terminology that is far more precise.

PE

[Ray Rogers]

If I am understanding the drawing correctly, each layer flows one on top of the other, and they all meet up at the other end without blending together? If so, that's incredible! What keeps them from combining to form one?

Essentially, I think it is differences in viscosity, but as PE mentions, there are perhaps other aspects at play as well.

A related thing happens in the production of Soda-Pop;
A high viscosity sugar syurp can sit at the bottom of a bottle filled with low viscosity flavored water forever untill mixed by a good shake.
Once mixed, however, they stay mixed.

Kodak researchers working on Kodachrome noticed this same phenomona in their emulsions and that gave them the idea.

:o Also, it is interesting to note that this device may actually be a real product of Kodachrome research.

[Kirk Keyes]

So did someone shoot the projectionist or did someone break into the locked unattended booth and steal the projector? Perhaps it took a phonecall from theater operations 1,500 miles away to get someone to come to the theater and get the other projector out of storage and boot it up.

I understand that all the shows across the country at that time had the same crash with the movie. It must have been an issue with the transmission of the digital movie.

[Ektagraphic]

I don't really see the point of Kodak-bashing. I'm grateful for the products they DO still offer.

Thank you! They still offer SIX diffrent Ektachrome emulsions! I think that quite a few in this highly digital age.

[Steve Smith]

If I am understanding the drawing correctly, each layer flows one on top of the other, and they all meet up at the other end without blending together? If so, that's incredible! What keeps them from combining to form one?

From what I remember from the Ilford tour a couple of years ago, this is the method used in their coating machine.

Not sure what stops them combining either!


Steve.

[Ian Grant]

Not quite the same as Ilford's cascade coating that we saw (last Autumn) where the paper is fed under the coating head.

The adjacent layers will mix very slightly and combine, but that should make no difference in practical terms, but as coating is relatively fast there's very little time for them to mix further as the gelatin sets quickly.

Ian

[Steve Smith]

'Cascade'. That was the word I was trying to remember.

From what I remember about the pilot machine we saw running, it seemed to look like the drawing in Ron's post with the application point just about level with the centre of the roller with the film moving up past it.


Steve.

[Ian Grant]

You're right Steve I was thinking of the Glass plate machine Even Kodak can't put that round a roller

Ilford held a Patent for cascade coating USP 3903843 which has drawings of the coating heads.

Ian

[Steve Smith]

Ilford held a Patent for cascade processing USP 3903843 which has drawings of the coating heads.

There was quite a large block diagram type of drawing of the cascade head in the main coating machine building too (if my memory is still working properly!).


Steve.