In practical terms, without a hardener like Zebra Chrome Alum, silver gelatin emulsions can be susceptible to wrinkling or curling if exposed to fluctuating temperatures or certain chemicals that soften and swell the emulsion. By incorporating our hardening agent into your workflow, these concerns become a thing of the past.
The precise amount of Chrome Alum required depends on the gelatin-water ratio of your specific emulsion, necessitating a bit of experimentation with your recipe. However, a reliable starting point, suitable for most emulsions including FOMA, is as follows:
To create a 2% Chrome Alum Hardening Solution:
- Combine 100ml of distilled water with 2g of Zebra Chrome Alum Hardening Agent.
- Mix until the Chrome Alum is fully dissolved.
- Add 2.5ml of this solution to every 100ml of photographic emulsion.
It’s crucial to add the Chrome Alum just before the coating process and only to the portion of emulsion you intend to coat. Once introduced, the hardening process begins, even if the emulsion is kept at a consistent temperature to remain liquid. Therefore, adjustments to the amount of Chrome Alum used may be necessary based on your emulsion and workflow requirements. With Zebra Chrome Alum, you can confidently achieve superior results in your photographic endeavors.
