Lghtmtr is a simple light meter application for the iPhone to take light readings of scenes primarily for film photography. Lghtmtr is also a great tool for beginners to film photography to learn how exposure, aperture, ISO are all related as the app helps the user visualize these connections.

I developed this application after realizing that I already carry my phone with me where ever I go and because it would be nice to recover the space in my camera bag my regular light meter takes up.

Currently the application is very simple, though a few extra features are in the works. You take a reading of a scene with the camera, either using the iPhone to suggest a good exposure, or by clicking on a region of the camera’s view to better expose for that area. After an initial reading, you can then lock in and adjust the values for shutter speed, aperture, and ISO. Your adjustments will then make the app update the other non-locked-in values.


Early interface ideation to figure out how people should physically interact with the app.


The alpha design featured horizontal sliders to hold the selectable data, inspired by some an old Braun radio dial interface. This layout was problematic due to how the top row was hard to reach with a user’s thumb if interacting one-handed.


This was the refined alpha interface going with data arranged in columns as to alieveate the thumb reach issue. Added lock buttons to lock in particular a column of data. With the introduction of larger iPhone screens the bottom space got to be a bit too large and empty. Feedback suggested users were confused on how to interact with the app initially as interaction with the columns was disabled before a light reading was taken, but there was no indication that interaction was disabled.


Redesigned interface for iOS 8. Added support for a percentage based layout in XCode so the interface looks right from the iPhone 4S through the iPhone 6+. Some of the language changed to clarify what actions the user was asked to do. The data in the columns was greyed out on initial load to clue the user in that an initial reading must be taken before you can interact with the columns. Added a walkthough for first time the app is run. Added the ability to review the image from which the light reading was taken.
A few color theme studies when deciding to move towards a flat UI. None of these were very compelling, so everything needed to be rethought.