Nikon question

I would like to make more use of my 500mm mirror lens on my Nikon D50, but it's a pain to use because the D50 was a cheaper camera which doesn't support manual lenses very well. It will only work in full manual mode, doesn't give focus confirmation (which admittedly is not a huge problem, I can generally tell by eye) and doesn't meter or allow aperture-priority automation (which is a total PITA).

Short of buying a better body, the way around this is apparently to fit a special chip to the lens mount, which tells the camera that it's set to an arbitrary aperture and manual focus. Some info about these chips here:
http://filmprocess.ru/nikon_prog_en.htm

These seem to work out around £20 already fitted to a T2 mount, but I'm a bit skeptical of their reliability, they look like the chip would break off if you breathe on it hard. And to be honest my 500mm lens isn't a good one, it may not justify the expense, especially if it's likely to cause problems.

Does anyone have any experience of these mounts?

Picocon

Picocon used to be the annual one-day student SF convention at Imperial College in London. As of last year it became a two-day convention, this year taking place yesterday and today. It's cheap, it's the only regular SF convention in central London, and the venue is in walking distance of my home.

The trouble is that so far what used to be a fun one-day con with a lot of interesting content has become a somewhat less fun two-day con with padding.

Last year the programming was OK but not brilliant both days, I ended up skipping the Sunday because I wasn't feeling well.

Yesterday's schedule was reasonably good at first with two interesting items before lunch, another two after, but that was followed by two hours of turkey reading before a film in the evening, one I didn't particularly want to see. My tolerance for turkeys is not huge, as a result I was out of there by four or so.

Today's schedule was two interesting items before lunch, a two hour lunch break, one program item afterwards that was described by the one word "Golem", then two hours of "silly games" before a pub quiz. In the end I decided to give it a miss, because it was going to soak up a lot of time if the afternoon sucked. I have no idea how things actually turned out, but I got the impression that others made a similar decision.

My feeling here is that the move to two days may have been a mistake - students may like it, but if they want to attract more outsiders they really need to up their game considerably. And anyone who turns up on the Sunday only is likely to feel badly let down.

I'd be interested to find out what those who did attend today thought of it.