Light & Deep app icon

See before you shoot.

Light & Deep is an iPhone app. It's a rangefinder, a light meter, a director's viewfinder in one. Light & Deep is an iPhone app. It's a rangefinder, a light meter, a director's viewfinder in one. Plan your shots, develop an intuition for exposure settings, see the expected depth of field.

It's in beta on TestFlight. Everything unlocked, so you can test it out. Try it and tell me what works.

2.4 m 6x7 · 80mm · f/2.8

Runs on any iPhone. The depth measurement needs an iPhone Pro.

Three tools, one app.

Rangefinder. Light meter. Viewfinder.

Depth visualisation

Two ways of measuring distance:
Set a distance, and everything at that distance lights up. Pre-set your camera to the same distance, and you know immediately what is in focus.
OR
Place a point by tapping the screen, and you'll always see the distance towards that point.

Light meter

Point the camera at the scene. Set the ISO, and the app gives you the correct exposure settings. Aperture priority or shutter priority - you choose which one stays fixed.
Place a point on the screen, and the light meter turns into a spot meter - automatically adjusts the settings to correctly expose the chosen area.

Film format viewfinder

Pick a format and a focal length, and the frame lines change according to your choices. You see what fits, what doesn't, and how you want to compose your frame. Forty-nine formats available, from Super 8 to 20x24 inch.

A live preview of your depth of field!

Actual depth of field preview!
Based on aperture, film format, focal length and distance, the app calculates what will be in focus, and highlights it in a zebra pattern.

Forty-nine formats.

The usual ones, and a few I only hope to shoot with.

35mm

Full Frame, Half Frame, Cine, Panoramic, Sprocket

Medium Format

645, 6x6, 6x7, 6x8, 6x9, 6x12, 6x17, 6x24

Large Format

4x5, 5x7, 8x10, 11x14, 16x20, 20x24

Panoramic

XPan, 6x12, 6x17, 6x24, large-format panoramics

Digital

Full Frame, APS-C, APS-H, Micro Four Thirds, Digital Medium Format

Professional Cinema

Super 8, Super 16, Super 35, ALEXA 35, ARRI Large Format, VistaVision, 65mm, IMAX 15/70

Helpful little features.

0.5x ultrawide

Switch to the ultrawide iPhone lens for the wide focal lengths that won't fit the normal field of view. LiDAR still works in the middle of the frame.

Black & white preview

See the scene in monochrome to preview your black & white shot. It's a decent approximation of how a panchromatic film will render the same light.

Reference shots with metadata

Save a frame. Exposure, distance, format, and focal length get written in a strip along the bottom - so when you're in the darkroom a week later, you still remember your settings.

Light meter calibration

The default light meter calibration works well. Still, you can adjust the calibration offset for your iPhone to match your professional light meter.

Customize for your shooting style

Zebra colors. Crosshair styles. Frame styles. Grid overlays. Opacity. All of it adjustable.

World-space tracking

Tap a subject, and the measurement point stays on it while you move around. ARKit tracks the point from 3D space on every frame.

Made for you.

Large and medium format

The camera is massive. The setup takes time. Use the app to see how you want to position your camera, how to frame your shot, which lenses to choose and whether that ISO 100 film is actually enough.

Cinema and pre-production

A director's viewfinder, but with DoF visualization and a light meter built in. Scouti locations, compose your shots, and get a clear view of your lenses and settings before you even touch a camera.

People still learning the craft

Change the aperture. Change the format. Change the focal length. Watch the in-focus zone grow and shrink in real time. It's the fastest way to build intuition.

3D-printed camera builders and users

As fun as 3D-printed film cameras are, they often lack a good way to reliably frame the shot and nail the focus. Light & Deep solves it, as it replaces the light meter, range finder and viewfinder in one app.

Still in beta.

Free on TestFlight. Every feature unlocked.
No account, no payment, no tracking.
Try it. Tell me what breaks. Tell me what feels wrong,
or what's missing.

A few answers.

How do I become a tester?

Tap the TestFlight link above on your iPhone or iPad. Install TestFlight if you don't have it. Accept the invite. That's it. While the app is in beta, every feature is unlocked and there's no payment involved.

How far does the LiDAR reach?

About five meters, reliably. That's the range where a rangefinder matters most: portraits, still life, macro, close-quarters documentary. For landscape work you can use a depth-of-field calculator instead.

Does the depth display work in ultrawide (0.5x)?

Partially. LiDAR coverage is limited to the center of the ultrawide frame, and a small parallax offset is visible at close distances. Honestly a miracle I got it to work at all. And it's still useful for previewing the wide formats, and no other app I know of offers LiDAR rangefinding at 0.5x.

What devices does it run on?

Any iPhone or iPad on iOS 17.6 or newer. The light meter, viewfinder, and framing tools run on all of them. The LiDAR features - depth overlay, spot distance meter, depth-of-field preview - need an iPhone Pro (12 Pro or later) or an iPad Pro (2020 or later). Those are the models with a LiDAR scanner.

How accurate is the light meter?

Like other light meter apps, it calculates ISO, shutter speed, and aperture based on the camera sensor readout. Think of it as a reflective meter, comparable to in-camera metering on a modern digital body. If pre-set calibration doesn't match your external light meter, you can adjust the calibration offset in the setting for each iphone lens.

Can I use it for cinema or motion-picture work?

Yes. There are 11 cinema formats, from Super 8 to IMAX 15/70, and the depth-of-field calculation uses each format's own circle of confusion. I talked to a few DoPs already and am very open to suggestions on how to improve the app for that use case. Reach out to me if you have any feedback!

One more thing.

If you teach photography, or work as a DoP, or just need some specific features still missing from Light & Deep - reach out to me and we'll see what we can do!