Stopwatch for Timing Exposures

I have been struggling recently with exposures from 2 seconds to say 6 or 8 seconds. I have taken like many people to using an app for reciprocity compensation calculations. The app works fine as most of my exposures turn out ok. However relying on the built-in timer has not worked out for me. Hitting the button on the phone screen is not always reliable. I tend to miss it or not touch it well enough to start the timer. Then of course I have also opened the shutter only to find the timer just sitting there waiting to be activated. 

Now my panicked mind is trying to keep track of how many seconds have passed, deciding if I should close the shutter and start again and just generally running around in alarm. Longer exposures can be more forgiving. 

I think there are some possible solutions. The app could offer a countdown time to the start of the interval. 5, 4, 3, 2, 1, snap!, 6, 5, 4, 3, 2, 1, snap!. I also considered a small Arduino project to make a self-timed cable release. It would be very simple, a dial to set the time 1, 2, 4, 6, 8, 12, 16, 24, 32 seconds and T for instance and a start button. A solenoid or servo would actuate the cable release. Simple and accurate. 

While I considered this idea I was reminded of Ben Horne suggesting the use of an analog stopwatch. He has a short article here.  So I went and bought one on eBay for £25.

I have tried it a few times now and am converted. It has all the virtues he describes. I find it very intuitive to push the cable release and stopwatch at the same time. I was concerned about the sweep of the hand not being easy to gauge the time but it is very straightforward.  

There are some stopwatches that have a 30 second (instead of the one I have which is 60 second) dial. I couldn't afford those I found on that day. This would be somewhat better for counting the seconds. I would be careful about new stopwatches made in China as I found some are the size of wristwatches. I made sure they were about 2" or 50mm across. As for digital versions I think the analog version is bound to be easier to read. LCDs can be slow in the cold so the screen may not be clear as it updates. Also analog has no batteries one less thing to go wrong.