silver bromide (plate) emulsion

hi

i was wondeirng if anyone can point me in the right direction to find a formula for a

silver bromide emulsion suitable for coating dry plates?

i have used liquid light and other liquid paper emulsions, but am looking now to

make something with a little more "speed" and something that might more than blue

sensitive ...

any suggestions?

thanks in advance!

john

With the caveat that the "fast" emulsions given in this early 20th century text are probably about ISO 25 or 32, and the panchromatics are probably another stop or more slower in red than in blue, here's the only reference I've seen (on line or in print) for making more than the simplest of emulsions:<p>

<a href="http://rmp.opusis.com/documents/photoemulsions/photoemulsions.htm">Photo Emulsions</a>

This is a link to a dry plate "recipe" using liquid light as the emulsion main ingredient. Looks relatively easy:<br>

<a href="http://www.alternativephotography.com/process_dryplate.html">The silver Gelatin Dry Plate Process</a>

<br><br>

This also looks intriguing:<br>

<a href="http://groups.yahoo.com/group/yahoo-cls-DryPlateEmulsions/">Dry Plate Emulsion Laboratory</a>

thank you donald & philippe!

i appreciate your links :)

i actually contacted kodak this morning and they have publication on how to make a

simple silver bromide emulsion. it doesn't look very complicated, and if i can find the

time, i have a feeling i will probably give it a go :)

i also contacted rockland colloid and asked them about liquid light - turns out it is a

silver bromide emulsion kind of like the formula from kodak.

if/when i make a batch, i'll check back and post an image :)

thanks again!

-john

Hi John; it's me, Mark from Frisco. An orthochromatic (blue+red sensitive) emulsion is much more difficult to make than the simple blue-sensitive type. I remember ligthly reading up last year on the nature of this, and it was called color photography in the 19th. century. Since my interest was only in blue sensitive types, I didn't copy down the information, but here's the book I believe the information was in:

The Photographic Instructor, by W.I. Lincoln Adams, 1888.

As for increased speed, since you've used several paper emulsions, you might try hypersenstizing the fastest one you have. There were a number of ways to accomplish this, none of which I've tried; but again, the old books have the real nitty gritty on this.

If you can manage a trip to George Eastman House in Rochester you'll find an immensely rich storehouse of books on dry plates. If I can manage a trip to the East Coast I'll make my pilgrimage there.

-Good luck, Mark.