I'm having blog hosting problems. Right now only older posts (from 2014 and earlier) are available. The whole blog may disappear again from time to time. Sorry. I hope to get this resolved within a few days.
UPDATE: OK, I think the situation is resolved, more or less. Some old images have been lost along the way, but they probably won't be missed. I'll try to get things more organized over the next few days. !!!