Zone System exposure, made usable in the field.
Zones helps serious film photographers place tones, calculate exposure, apply real-world adjustments, assign development targets, and leave the field with a clean record of the work.
For sheet film and roll film / Exposure adjustments, notes, and CSV export / No location tracking in phase one
Place tones and calculate exposure
Apply filters, bellows, reciprocity, and manual compensation
Assign development targets for sheet or roll workflows
Export a clean CSV log when the session is done
How it works
Start the session
Set camera, film stock, format, and ISO rating to begin a field session.
Place tones
Meter subjects and assign them to zones based on your reading and intent.
Calculate exposure
The app calculates aperture and shutter speed from your placements.
Apply real adjustments
Add filters, bellows extension, reciprocity failure, and manual compensation.
Finish with a usable log
Assign development targets, add notes, and export a CSV record of the work.
Field workflow details
Place Your Zones
Zones does not require a reference photo. The log is based on meter readings, zone placement, and your exposure decisions.
Adjustments stay attached to the exposure
Filters, bellows extension, reciprocity failure, and manual compensation are recorded with each exposure, not buried in global settings.
Development intent stays practical
Assign N, N+1, or N-1 to each sheet or a single target for the whole roll. The app does not attempt to calculate development time.
Editing stays open
Sessions can be edited, re-opened, or exported at any time. The CSV is yours.
Sheet film and roll film
Sheet film
SHEET COUNT AND BACK ASSIGNMENT
Track individual sheets and assign them to film backs for organization.
N, N+1, N-1 LOGIC
Assign development targets to individual sheets based on contrast intent.
Roll film
SINGLE DEVELOPMENT TARGET
Assign one development target for the entire roll session.
SESSION ORGANIZATION
Sessions are organized by camera, film, format, rating, and status.
The Zone System is demanding enough in the field. Recording it should not make it harder.
Zones is built for photographers who need a clean record of zone placement, exposure calculation, and development intent. It does not attempt to automate judgment. It gives you a structured place to record the work while you are still in front of the subject, and a usable log when the session is done.
Interface
Download Zones for iPhone
Available now on the App Store for iPhone.