View Full Version : Blue Sensitizer

12-14-2011, 05:09 PM
For the first time, I am now considering a blue sensitizing dye. This is because, in my current emulsion the portions with sensitizing dyes are each considerably faster than the portion with no dye. Any suggestions as to something currently availible?

12-14-2011, 05:27 PM

PE addressed blue dye in a post (http://www.apug.org/forums/viewpost.php?p=1250766)a while ago.
AFAIK, dye is used to sharpen the response in the blue end, not to increase sensitivity. I haven't found anything in the usual places (Sands, Honeywell etc.,)

12-14-2011, 11:54 PM
Thanks Ian,
I think that I will do some speed comparisons between each of the 3 parts tomorow - Frieday. Then I will get a better idea of how to best blend the 3 parts. .
P.S. I think that I may have just solved my problem, in my head. If I am correct, the explanation will be embarising. So I may not say anything more.

12-16-2011, 04:47 PM
Guess what! I was correct! The explanation is embarrasing! So, disregard everything that I have written on this thread.


12-16-2011, 05:11 PM
Forget what? What thread? :whistling:

Photo Engineer
12-16-2011, 07:17 PM
The idea is to put enough green (or red) dye on an emulsion to kind of match the speeds of the emulsion to the two regions of the spectrum. And, this is speaking of the area under the curve, not the raw speed at any one wavelength. After all, we use white light for most all exposures.

So, this is a hard measure to make. I devote a page or so to this with figures in the book.