Light Meter LuMe
Film Light Meter & Calculators
Only for iPhone
Free · In‑App Purchases · Designed for iPhone. Not verified for macOS.
iPhone
LuMe is a pro-grade light meter and exposure calculator built for film photographers. Whether you're shooting medium format on a Mamiya, large format on a 4×5, or 35mm on a Leica, LuMe gives you the exposure intelligence your film camera doesn't have.
METERING MODES FOR EVERY SITUATION
• Matrix — averages the whole scene for balanced exposures
• Center-weighted — emphasizes the middle, like a classic SLR meter
• Spot — measures a small area you tap, just like a 1° spot meter
• Zone System — Ansel Adams' tonal mapping (Zones I–IX) right in your viewfinder
MULTI-POINT SPOT METERING
Place up to four spot markers anywhere on your scene. Read each EV at a glance, evaluate contrast range, and place tones with intention.
LIDAR SPOT DISTANCE (on Pro devices)
See the physical distance to any metered spot — useful for hyperfocal setup and verifying focus on rangefinders and manual-focus lenses.
RECIPROCITY CORRECTION FOR EVERY FILM STOCK
Long exposures don't behave linearly on film. LuMe applies the Schwarzschild exponent for your stock — Tri-X, TMax, Portra, Ektar, Velvia, and more — so you don't need printed tables in your bag.
DEPTH OF FIELD CALCULATOR
Hyperfocal distance, near limit, far limit — for 35mm, APS-C, medium format (6×4.5, 6×6, 6×7), and large format (4×5). One tap.
FLASH GUIDE NUMBER CALCULATOR
GN, distance, power fraction → f-stop. Solved.
LIVE EXPOSURE TOOLS
• Histogram overlay
• Highlight/shadow clipping warnings
• ND filter compensation
• Aperture priority & shutter priority
• Exposure compensation dial
• ISO and shutter range constraints (cap at your film speed)
BUILT FOR THE WAY FILM PHOTOGRAPHERS ACTUALLY SHOOT
• Spot meter a high-contrast scene; place highlights on Zone VII
• Apply reciprocity for a 30-second exposure on Tri-X
• Calculate hyperfocal for landscape work on Portra 400
• Verify a flash setup before burning a frame
LuMe replaces your handheld meter, reciprocity card, DoF chart, and flash calculator with one tool that fits in your camera bag.
Available in 16 languages: English, German, French, Spanish, Italian, Portuguese, Dutch, Swedish, Polish, Turkish, Russian, Arabic, Japanese, Korean, Chinese (Simplified & Traditional).
LUME PRO
• $6.99 USD for lifetime access
Privacy policy: https://lume.contraststudio.app/privacy.html
Terms of Use: https://lume.contraststudio.app/terms.html
• Consolidated the Settings page
• Bug fixes
The developer, Contrast Studio, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Linked to You
The following data may be collected and linked to your identity:
- Purchases
- Identifiers
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- Contrast Studio LLC
- Size
- 15.6 MB
- Category
- Photo & Video
- Compatibility
Requires iOS 16.0 or later.
- iPhone
Requires iOS 16.0 or later. - Mac
Requires macOS 13.0 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 1.0 or later.
- iPhone
- Languages
English and 15 more
- English, Arabic, Dutch, French, German, Italian, Japanese, Korean, Polish, Portuguese, Russian, Simplified Chinese, Spanish, Swedish, Traditional Chinese, Turkish
- Age Rating
4+
- 4+
- In-App Purchases
Yes
- LuMe Pro Lifetime $6.99
- LuMe Pro Lifetime $6.99
- Copyright
- © 2026 Contrast Studio LLC