Reciprocity easily calculates exposure settings for great pictures every time. Great for anyone, from beginners to seasoned photographers.

* Instantly calculate Exposure value, ISO speed, Aperture, or Shutter Speed
* Enter values either directly or via a slider
* Option to choose Exposure value from a list of common scenes
* Convert exposure settings between different cameras or film speeds
* Save the reciprocity failure values of multiple films for future use
* Round exposure stop values to 1/2, 1/3 or both
* Built-in timer for exposure longer than 2 seconds
* Detailed user guide to help beginners make use of their camera's manual settings

What's New

Version 2.0

* This major update to Reciprocity has the same classic look and functionality, but has been rebuilt under the hood for forward compatibility and future improvements.
* As requested, you may now choose to round values to 1/2, 1/3 or both exposure stops in settings.
* Reciprocity failure can now be saved for multiple films and be selected as needed.
* Reciprocity is now universal and will work on your iPad too!

Ratings and Reviews

Native shutter speeds are off!


Native shutter speeds in full stops are: 1sec,1/2,4,8,15,30,60,125,250,500,1000

Developer Response

Version 2.0 now uses native shutter speeds, and also allows you to select between 1/2, 1/3, or both 1/2 and 1/3 stops.

Good App


This is a one of the best apps I've found for figuring general reciprocity failure for most films. While I have only used it with a couple of films, I have found it to be accurate. This app would be great if it had a timer built in. Right now I have to exit the program, start a clock/timer program for timing the exposure. It would be great to have a timer that would automatically enter the shutter time then when the start button is hit it would count down from between 5 to 10 seconds. Then make a warning sound to start the exposure, then make another warning 5 to 10 seconds before the the end of the exposure. There is room at the bottom for the timer. Thanks!

I love cinematography, I hate math


It's always nice to have calculators like this on set. Without it, I'd imagine making a huge fool out of myself doing the math in head or by hand.. Greatly appreciated!


Scott Lagaly
15.5 MB
Photo & Video
Requires iOS 8.0 or later. Compatible with iPhone, iPad, and iPod touch.
Age Rating
Rated 4+
© Scott Lagaly
In-App Purchases
  1. Additional Features and Remove ads $0.99


  • Family Sharing

    With Family Sharing set up, up to six family members can use this app.

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