I've been doing a lot of Android development lately... after 20 years of c#. I've been thinking about applications of Android code in the darkroom. Now I've come across this thread! If you are interested, we can put our heads together to build more features into the project?
Jeff & John, it would be great if a driver for a (simple) USB or Bluetooth relay card controlling the enlarger could be integrated in the F-stop timer app. For example, something like this instead of a Arduino system as the Bluetooth receiver and relay controller. The lack of the app controlling the enlarger directly makes it not all that usefull I find. So in my opinion, that should be the first new feature. Unfortunately I'm not a programmer so I can't help out there.
Hello
I have another idea to controlling enlarger from app. Almost every android phone have led diode as flashlight or torch. If it would be possible add an option to turn on flash to time of turning on enlarger (time of exposure). It is possible to make device to turn on and of enlarger with light of phone flash. This device could work with photodiode or photo transistor. Something like night lamp that turn on when is dark, but in opposite direction. Then you can put phone on that device and flashing light will activate enlarger light.
Yes it's possible but probably not desirable. Unless you covered the torch light and photodiode pair adequately, you world risk fogging your paper. I suppose if the phone was housed in a light tight cradle, but then you have the problem of creating so many different cradle sizes.