Wet Collodion vs. Emulsion making & the difficulties involved

Photo Engineer said:

Dan;

Mercury and mercury salts cause severe fog in photo materials when not used in the correct manner. Merthiolate is one of them.

We had a case of severe fog on a product line that was traced to mercury and it was found that one of the line workers had visited a relative and slept in a bed used by another individual who had had a cut treated with merthiolate.

The transfer of the merthiolate onto the sheets from one person and then to the other person and then to the film was enough to cause serious defects.

This was one of our courses at EK. Things to avoid.

So, we had special pens, as the ink in most pens and markers can cause fog in films. We have special insect spray, as most sprays can cause fog. The list goes on and on and we had to take classes in all of this.

BTW, Dye Transfer paper used a Thorium salt and was mildly radioactive. They used special equipment and a special machine to make it. If they had not, the accumulated radioactivity would have affected other products on the same machine. And, all Kodak buildings in which film is made have footbaths to remove any outside dust. We have a special laundry and labware cleaning facility and wear specical outfits to prevent contamination.

I would guess this adds to the Kodak quality and also the cost.

PE

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htmlguru4242 said:

Would people recommend the John Coffer set or Quinn Jacobson's book?

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dslater said:

Wow - very interesting. So did Kodak have some kind of store at the plant where employees could buy things like pens and markers? Does pen and marker ink still cause fogging or did they used to have mercury in them?

Dan

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Photo Engineer said:

I had 2 passes. One for the plant keyed to buildings and areas that I could go to, and another for stockrooms. I could go to a stockroom and get a pen, pencil, graph papers, wratten filters, step wedges, tablets, safe-flashlights and regular flashlights, chemicals, labware and on and on and on. They scanned the card and my project would be charged. I got anything I needed that way.

Actually, I had 3 passes. One was for exit from the plant carrying very confidential material and this pass exempted me from inspection, as the gate guards could not see the contents of my briefcase.

PE

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Photo Engineer said:

Actually, I had 3 passes. One was for exit from the plant carrying very confidential material and this pass exempted me from inspection, as the gate guards could not see the contents of my briefcase.

PE

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