Comparison

ZoneCalc vs Darkcloth

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

ZoneCalc

This app assists photographers in precisely calculating exposure and tonal placement using Ansel Adams' Zone System. It offers features for metering, reciprocity correction, and development adjustments, with options for multi-point measurements and data export.

Highlights
  • Zone System exposure calculation
  • Multi-point metering
  • Reciprocity correction
  • Development adjustment recommendations
  • Film-specific development times
  • Calculation history and export
Features
Read full description

ZoneCalc — Zone System Calculator ZoneCalc is a precision tool for large format, medium format and 35 mm photography following Ansel Adams' Zone System. Built for photographers who work with a spot meter, develop their own negatives, and want full control over exposure and tonal placement. METERING In Classic mode, enter the shutter speed for the deepest shadow with detail (Zone II) and the brightest highlight with detail (Zone VIII). ZoneCalc returns the shutter speed for Zone V — 18 % middle gray — the exposure you set on the camera. Multi mode accepts any number of measurement points across the scene. The app auto-assigns each point to a zone; drag pins on the zone strip to express your creative placement intent. RECIPROCITY For exposures above one second, the Schwarzschild effect is corrected automatically: t_corr = t_nom ^ p, using the film-specific exponent. The corrected camera time appears directly in the result card. The shutter speed list extends to 30 minutes. Films with reciprocity data: Ilford HP5+, FP4+, Delta 100/400, Kodak Tri-X, T-Max 100/400, Kodak Portra 160/400/800, Leica Monopan. N-RATING & DEVELOPMENT ZoneCalc compares the scene's dynamic range against the film's usable latitude and proposes a development adjustment — N−2 through N+2. For each film, concrete times are shown for common developers: D-76, Rodinal, HC-110, XTOL, ID-11, T-Max Dev — with dilutions per Massive Dev Chart and manufacturer recommendations. HISTORY & EXPORT Every calculation can be saved with a note and the chosen developer; two entries can be compared side by side. The complete result — shutter speed, reciprocity, N-rating and development times — exports as an image for the darkroom or for sharing via AirDrop, message or mail. DESIGN The interface follows the visual language of classic Leica instruments: monospaced typography, warm amber accent, hard edges instead of rounded corners. Fully localized in English and German, all-dark throughout — optimized for darkroom and field use. ZONECALC PRO Classic two-point metering with Zone V calculation and the zone strip are free. The one-time Pro upgrade unlocks: — Multi-point metering with interactive zone assignment — Reciprocity correction and N-rating — Development recommendations with times per developer — Save, compare and image export One app, no subscriptions, no data collection. All calculations run locally on device.

About

Darkcloth

Read full description

"A good photograph is knowing where to stand." — Ansel Adams Darkcloth is a field viewfinder for technical and view cameras. Use the phone camera to preview the frame before you set up the camera. Choose a film format and focal length, add rise, fall or shift, compare lenses, and check level. It is meant for planning the photograph, not replacing the ground glass. Included tools: • Framelines for 6×7, 4×5, 8×10 and custom formats • Multiple focal lengths at once for lens comparison • Rise/fall and shift preview over the live scene • Reflected-light meter with average and spot readings • Reciprocity correction for common film stocks, plus custom stocks • Roll and pitch level • Scheimpflug tilt visualiser with near/far depth-of-field readout Darkcloth was made alongside the Fysh FTC-1, but it is not locked to that camera. It works with other technical-camera and view-camera workflows. No account is required. No photos are uploaded.

Screenshots

ZoneCalc4 screens
Darkcloth4 screens

Verdict

The call

The clearest difference is in-app purchases: Darkcloth at none against ZoneCalc's 1. On price, update cadence, ads and device support there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. ZoneCalc sells 1 one-off in-app purchase. Darkcloth asks for nothing beyond the download.

UpkeepUpdate frequency

ZoneCalc ships an update every 3 weeks, Darkcloth every 10 days. The most recent releases landed on October 12, 2026 and October 14, 2026 respectively.

Scorecard1 real difference · 8 level
ZoneCalc versus Darkcloth: the parameters behind the verdict, then further details
ParameterZoneCalcDarkcloth
PriceFreeFree
Rating5.0 (2 ratings) — better—
Number of ratings2 — better—
Update frequencyEvery 3 weeksEvery 10 days — better
AdsNoNo
In-app purchasesYesNo — better
MonetizationFreemium—
DevicesiPhoneiPhone
Requires iOS17.616.0 — better
Further details — not scored
Size3 MB2 MB
Age rating4+4+
DeveloperJuergen SukLACHLAN M FYSH

In-app purchases

1 purchases

ZoneCalc

One-time1
  • ZoneCalc Pro$3.99
None

Darkcloth

No in-app purchases

Questions

Is ZoneCalc free?
ZoneCalc is free to download, with in-app purchases available.
Is Darkcloth free?
Darkcloth is free to download, with no in-app purchases.
Do ZoneCalc or Darkcloth have ads?
Neither ZoneCalc nor Darkcloth shows ads.
Which is updated more often, ZoneCalc or Darkcloth?
ZoneCalc ships an update every 3 weeks, and Darkcloth every 10 days. Most recently, ZoneCalc was updated on October 12, 2026 and Darkcloth on October 14, 2026.

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