I have a cheapish 500mm Opteka mirror lens that rarely get much use, in part because there simply isn't much use for a lens that long in my normal sort of photography, and in part because it's a pain to use - my Nikon D50 doesn't support metering or focus confirmation with non-electronic lenses, so I have to guesstimate every shot. Also, mirror lenses are never as sharp as the equivalent conventional lens, and can't be stopped down to improve depth of field.

I can do without it, since I have a good 28-300mm lens, but for occasional things (such as the next eclipse) it would be useful. So the main options are:

1. Keep it and live with its limitations.
   
2. Keep it but add a dandelion chip so that the camera electronics will work with it (about £20, and a setup procedure I'm not sure I fully understand and I'm not sure will work with the D50).
   
3. Look for a better lens with built-in electronics, autofocusing, etc. (very expensive unless I get really lucky).
   
4. Sell it and do without.

So since it was a bright day I took it out to the park and took a few photos - what I should have done, in hindsight, was compare it with the longest setting of the zoom, but I took out the wrong lens so ended up comparing pictures at 35mm zoom ("standard lens" for the D50) with the 500mm lens.


Crow - about the same distance in the two photos




Small goose - again, about the same distance




Albert Memorial, from the same camera position in all pictures









Looking at these pictures, I'm not convinced that the results are good enough to make keeping it worthwhile; I've reduced the size of the photos to fit to the page and they're still not looking as sharp as I would like, mainly because they seem to be a little out of focus. Although I didn't use a tripod, I don't think that camera shake is the issue, most were taken at 1000th of a second or shorter exposures. Overall, I could probably get better results by using the long zoom at 300mm and cropping images.

What I think I'll do is keep it for now, try to use it a little more and see if the results improve with more practice, and at the same time watch out for an unlikely bargain in a conventional lens.

It was a windy day, and while I was in the park I passed the Round Pond, and was rather surprised to see this:












I was seeing spray going up three or four feet occasionally, though I didn't get a good picture of that, and blowing 10ft or more across the path, which for an enclosed pond is pretty impressive - not exactly an Arctic storm, but a lot more than I usually see in London.

In other news - the first 1gb RAM for the iMac G4 arrived this morning and it's now a 1.5gb machine. The other will hopefully arrive in the next day or two. I've also paid rather too much for a pair of the original speakers, which hopefully will turn out to work when I get them. Should add to the value when I sell it if they're OK.

And while I was out I visited a charity shop and got three Dr. Who DVDs for a fiver - two of the Beeb's New Who releases, plus the complete War Games 3-disk set with Patrick Troughton. Rather pleased about that...