Recently, I was asked if some tiny things could be done to adjust sharpness, increase highlight/shadow development, change grain size by fiddling with the chemistry that’s going inside the bottle while developing. More specifically,  the effects of adding Potassium Bromide (KBr) and and whether you might end up with some crispier images with bigger grain.

The answer to all the above questions is Yes. But in this post we will specifically talk about the KBr.

Potassium Bromide Crystals

Potassium Bromide (KBr) is a restrainer. As explained elsewhere, any film developer has four components : Developing Agent, Accelerator/Alkali, Preservative and Restrainer. The job of the restrainer is to prevent the development of grains that received no light (or very little light).

So, if you are getting excessive fog (more…)