Finally got a few hours of time and put together an OS X app to act as a digital darkroom timer. Canon EOS 5D    ---    35mm    f/3.5    1/50s    ISO 100 I tried several methods of control, including a cheap silicone rubber keyboard, but found this $35 RF presentation remote works best. Note the photo-chemical proof cover. Canon EOS 5D    ---    35mm    f/3.5    1/125s    ISO 400 So far so good. Much preferable to some cheap timer that dies halfway through a development.