ƒ/Calc

ƒ/Calc is a calculator for photographic formulas. These formulas are at the heart of many interesting questions about photography. None of these formulas are difficult to compute with a scientific calculator, but doing it by hand is slow, tedious and error-prone. The faster you can get an answer, the faster you can get back to shooting. Or, you can take the same time to learn the answer to more questions! When you let ƒ/Calc do the hard work, you gain an intuitive feel for what the results mean, because you can quickly try new input values to see how they affect the result.

To learn more, you can read through the user manual. The manual is also available in printable form (PDF, 355 KB).

Use It Online for Free

ƒ/Calc is available in several versions, one of which runs right inside your browser. It has all of the core functionality of the desktop version, and there is no charge for using it. You may find that it does everything you need.

Try It on Your Computer

There is also a “local” version of ƒ/Calc which works just like the online version, but it is more powerful.

ƒ/Calc Local lets you work with it while you aren’t connected to the Internet. If you’re already carrying a laptop with you on your photography expeditions, why not take ƒ/Calc along?

ƒ/Calc Local also has more features than ƒ/Calc Online. Currently, the main thing the Local version has over the Online version is that it lets you edit the lens and imaging area tables. If you own lenses or cameras ƒ/Calc Online doesn’t know about, this lets you teach ƒ/Calc about them immediately.

As features are added to the Online version, the Local version will get them too, but not always vice versa. There are several features on the wish list already that will only go in the Local version.

ƒ/Calc Local runs on any computer that supports the Adobe® AIR™ runtime. Currently, this is Windows 2000, XP or Vista, or Mac OS X 10.4 and up. They’re promising a Linux version some time this year. (In the meantime, ƒ/Calc Online works fine on Linux.)

Once you have the AIR runtime installed — which only needs to be done once — you can install the ƒ/Calc Local package (version 2.0.0, 868 KB).

While it’s still in beta, the Local version of ƒ/Calc is also free to use. It will be inexpensive shareware when it’s released, probably around $10.

Contact Me

Due to the spam epidemic, I’m trying to keep my email address private. There is a form on this page that will let you send email to me, but you need Javascript enabled to see it. I apologize for the hassle, but this is a necessary defense against spammers. Bots can send email through a web form just as well as through a mail server, but they can’t abuse a web form they can’t find. :)

Other Versions

Palm

There is a Palm version (ZIP, 66 KB) of ƒ/Calc which will run on Palm OS 3.1 or higher. It is currently still at version 1.14, so it lacks several of the features of the versions above. As soon as version 2.0 of the Online and Local versions are completed, I’ll be updating this one to come as close to feature parity as I reasonably can, given the limits of the platform. No promises on when that will happen, though.

The Palm version is shareware, and currently costs $8 to register. The fee will go up to match the Local version when I finish version 2.0 for the Palm, but the upgrade fee will just be the difference between the two.

Will You Make a Version for My Favorite Device, Too?

I’m just one guy, so I only port ƒ/Calc to platforms I personally use.

I use OS X, Linux and Windows daily, so ƒ/Calc runs on them.

My cell phone is a Palm Centro, which explains the existence of the Palm version.

I got an iPod Touch recently, and so may port to it at some point. It will have to wait until after v2.0 for the Palm, however.

I am happy with my current phone and PDA choices, so please don’t ask if I will port to other types of devices. StyleTap may be available for your device, which will let it run the Palm version.