Alt Exposure Cal and washout

Alt Exposure Cal & Washout helps you lock in a reliable, repeatable standard exposure for alternative photographic printing — and track your washout time alongside it.

Stop guessing. Start calibrating.

Designed for UV-based and contact printing processes, this app turns step wedge testing into a structured, repeatable system. Enter your baseline time, identify your first max-black step (or first clear white when calibrating polymer), input steps-per-stop — and the app calculates your standard exposure instantly.

Then record what actually worked.

Made for:

Cyanotype
Platinum / Palladium
Salt Printing
Carbon
Photopolymer
Gum Bichromate
Van Dyke
Other alternative processes

What it does

• Calculates a precise standard exposure from a step wedge
• Includes a simple process picker for fast logging
• Records washout time alongside exposure
• Optional notes for paper, ink, aquatint timing, coating variations, humidity and more
• Clean, newest-first log so your most recent calibration is always at the top
• Entries remain editable as your process evolves
• Export exposure records to Google Sheets for long-term archiving

Washout tracking

Washout timing can be recorded and adjusted to suit your working method. It is stored locally in the app so you can refine your preferred timing over multiple sessions.

Export made simple

Exposure records can be exported to Google Sheets using a small Apps Script (instructions included in-app). Each export includes:

• Date
• Process
• Standard exposure
• Paper
• Ink
• Notes

Your sheet automatically keeps the newest records at the top so comparisons across sessions remain quick and practical.

Why it helps

Alternative photographic processes are sensitive. Paper batches change. Humidity shifts. UV units age. Coating thickness varies.

This app helps you:

• Compare exposures across papers
• Track seasonal differences
• Record washout variations in one place
• Build a clean archive of what truly worked
• Reduce wasted materials
• Develop repeatable standards

Built by a practising alternative process artist, for artists who value precision without unnecessary complexity.

Terms of Use (EULA)
https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

Privacy Policy
https://itsasalfordthing.squarespace.com/privacy-policy-exposure-calculator

Happy printing.