I went to a night sky photography talk on Tuesday. The presenter talked a bit about tips on camera lenses, exposures; then showed a raw image and prepared to demonstrate how to process it to bring out the details.

His slides disappeared, the screen went blank, and then ... nothing. He wrestled with his laptop for a while. Finally he said "Looks like I'm going to need a network connection", left the podium and headed out the door to find someone to help him with that.

I'm not sure what the networking issue was: the nature center has open wi-fi, but you know how it is during talks: if anything can possibly go wrong with networking, it will, which is why a good speaker tries not to rely on it. And I'm not blaming this speaker, who had clearly done plenty of preparation and thought he had everything lined up.

Eventually they got the network connection, and he connected to Adobe. It turns out the problem was that Adobe Photoshop is now cloud-based. Even if you have a local copy of the software, it insists on checking in with Adobe at least every 30 days. At least, that's the theory. But he had used the software on that laptop earlier that same day, and thought he was safe. But that wasn't good enough, and Photoshop picked the worst possible time -- a talk in front of a large audience -- to decide it needed to check in before letting him do anything.

Someone sitting near me muttered "I'd been thinking about buying that, but now I don't think I will." Someone else told me afterward that all Photoshop is now cloud-based; older versions still work, but if you buy Photoshop now, your only option is this cloud version that may decide ... at the least opportune moment ... that you can't use your software any more.

I'm so glad I use Free software like GIMP. Not that things can't go wrong giving a GIMP talk, of course. Unexpected problems or bugs can arise with any software, and you take that risk any time you give a live demo.

But at least with Free, open source software like GIMP, you know you own the software and it's not suddenly going to refuse to run without a license check. That sort of freedom is what makes the difference between free as in beer, and Free as in speech.

You can practice your demo carefully before the talk to guard against most bugs and glitches; but all the practice in the world won't guard against software that won't start.

I talked to the club president afterward and offered to give a GIMP talk to the club some time soon, when their schedule allows.