Exposed is a free program for PalmOS-based handhelds that suggests aperture/shutter speed combinations for your camera based on parameters you enter (like film speed, lighting, etc.). I make no guarantees about the quality of these suggestions. Actually, I guess I can guarantee that they'll definitely be wrong in certain circumstances. Use it completely at your own risk.

Now that you've read the disclaimer, you can download Exposed here

Installation instructions:

Download the PRC file to your computer, then use the HotSync Manager software to install the PRC to your handheld. To the best of my knowledge, it'll work with most PalmOS based handhelds. Lemme know if you find otherwise.

Usage instructions:

• Start the app by tapping on the Exposed icon in the list of applications on the home screen.
• Tap the button corresponding to the film speed you're using.
• Pick the item from the list of lighting conditions that most closely matches the light.
• Select Aperture for "Aperture Priority" mode, then select the desired f-stop from the list. The correct shutter speed will be displayed.
• Select Shutter for "Shutter-speed Priority" mode, then select the desired shutter speed from the list. The correct aperture will be displayed.
• If the calculated aperture or shutter speed is too slow or fast/big or small, a message is displayed at the bottom of the screen.
• The program remembers the film speed from session to session, but not other settings.

A little background:

I wanted to get started taking some pictures with my grandfather's old Rolleiflex camera. I don't have a light meter (and I don't really want to buy one), so I started reading about stuff on the web. I found this great exposure calculator online, but couldn't find a (free) version for the PalmOS. So I wrote one.

It's close to correct most of the time, but when you start talking about low light levels (or slow film), something called reciprocity failure happens. I don't take that into account - you're on your own.

Got some feedback? Lemme know.