CalcuLight

CalcuLight is a powerful and intuitive light meter app designed for today's film photographers who want more advanced metering capabilities than what a handheld light meter can offer.

METERING MODES

Center Weighted: Classic center focused metering (approximately 30 degree field of view), similar to vintage film cameras.

3D Matrix: Full frame averaging for tricky scenes. Uses your iPhone's extensive EXIF data for fast and accurate readings.

Spot (Pro): Measure a precise 5% area of the frame. Tap anywhere to position the metering point.

Calculated (Pro): Tap up to five areas and receive an averaged exposure reading. Ideal for high contrast scenes and Zone System workflows.

EXPOSURE CONTROLS

Shutter Priority: Set your shutter speed. CalcuLight calculates the aperture.

Aperture Priority (Pro): Set your aperture. CalcuLight calculates the shutter speed.

EV Compensation: Per shot exposure adjustment in full, half, or third stops.

ISO, shutter, and aperture (Pro) values are available in full, half, or third stop increments.

ZONE SYSTEM VALUE DISPLAY (Pro)

When enabled, displays Zone System value overlay, showing the current zone from O to X alongside your reading.

In Calculated mode, each metering point displays its own zone value for advanced exposure control.

LIVE HISTOGRAM (Pro)

Real time RGB histogram overlay to detect clipped highlights and blocked shadows before you shoot.

Toggle between combined RGB, red, green, and blue channels.

LOG BOOK (Pro)

Save every reading with full exposure data, metering mode, GPS location (Choose precise or general) and timestamp.

Notes area will be pre-populated with captured values in Calculated metering mode.

Easily export your shooting log as CSV or JSON. Ideal for tracking exposures alongside film rolls.

DISPLAY OPTIONS

Light readings in EV, lux, and cd/m²

Light and dark themes optimized for personalized readability

Portrait and landscape support

MULTI-LANGUAGE SUPPORT

English, 简体中文, 繁體中文, 日本語, 한국어, हिन्दी, Русский, Deutsch, Français, Español, Português, Nederlands

FREE vs PRO

We designed CalcuLight to focus on simplicity and ease of use. The FREE version is completely ad-free and will satisfy over 90% of film shooter's needs when it comes to exposure metering.

Free version features:

Center Weighted metering

3D Matrix metering

Shutter Priority metering

EV compensation

Single metering mode

Theme switch

Pro version:

All free version features

Spot metering with adjustable area

Calculated metering

Aperture Priority metering

Vintage camera shutter speed options

Zone System overlay

Live histogram

Log book with optional GPS location recording

Continuous metering mode

Global EV offset

Exposure settings range limits

Experimental features (lens switch)

You can try Pro version at no cost for 14-days. After that, you can access the Pro version in two ways: Pay as you go for only $0.99 USD per month to access all Pro features (cancel any time); or $14.99 USD for lifetime access to all Pro features and future updates.

Privacy Policy:

https://calculight.ocutrain.com/privacy-policy.html

Terms of Service:

https://calculight.ocutrain.com/terms-of-service.html