DIY f-stop enlarger timer (based on Arduino)

This post is to announce my DIY f-stop enlarger timer project. The timer is built upon the Arduino platform. The timer has the basic features and and was designed with easy-of-use in mind rather that to contain a long list of advanced features such as programming of multi-step dodge/burn sequences.

The timer can be seen on the link below, where the interested reader should also be able to find source-code and schematics needed to build their own.

http://www.henpe.se/cms/darkroom/articles/12-fstop


Compared to other well known DIY f-stop timers such as e.g. the one by Brodie-Tyrell ( http://www.brodie-tyrrell.org/fstoptimer/ ), the one I have built has a slightly different user-interface. Build your own and according to taste! Enjoy!

(If you decide to build your own timer and improve on my prototype, I would be happy to hear about it.)

/Henrik

Thanks for sharing!

Thanks for sharing, and for making a simpler design than the other one you linked to. I think I have everything here to make your design except maybe some time, and I will leave out the usb connectivity to make it cheaper with a bare bones Arduino. I don't think the firmware would need updating so often that opening up the timer to access the chip would be an issue for me.

Thanks Henrik - that looks like a great timer. Similar in it's minimal design to Nicholas Lindan's fantastic f-stop timer. I don't think he's making them anymore, and having a backup plan is something that is important to me. I'll add it to my list of projects!

Nicely done!

Neal Wydra

This is amazing!

Thank you, Hendrik,
I just discovered your design on internet after google on f-stop timer diy.
Asked if one on apug already build it. Spijker pointed me this thread.
I will build it one of these days and post my findings.

Great. I have done some updates to the firmware recently that I will try to push to my site asap. I will post here when it is done.

Also, much have happened to the Arduino platform since I built my timer and now days there are lots of interesting shields and add-on modules easily available. For instance AdaFruit, and others, offer display-units with integrated keyboards that communicate with the Arduino over i2c. If you are reasonably familiar with the Arduino I would at least consider to replace my solution using a priority bit encoder (PBE) with an i2c solution instead. It will only require minor adjustment to my firmware I believe and it will require less soldering to put the timer together I suspect.

Nice!

I've always thought of making my own darkroom timer but not to that complexity. Looks like a cool project