Anyone interested at £475 including shipping?

For sale: Pentax DA 12-24mm f/4 with lens hood, caps and box

This is a great lens, but I just don't use it enough to justify keeping it. It's been very lightly used and is in near mint condition. Includes original lens hood, front and back lens caps and original box (slightly scuffed at corners).

£520 including Royal Mail Special Delivery to UK addresses. PM me if you have any questions.

Black paint is sometimes used to cover serious defects in lenses, such as chips in the glass, which would scatter a lot of light. Damage to the coating probably won't actually scatter much light, just slightly increase the the strength of specular reflections from the surface. This will increase the level of any flare and reduce contrast. If it's a small defect then most of the lens area is still coated, and I would expect any effect to be very small, and probably completely undetectable.

If you can't see any degradation of your images then I wouldn't worry about it (although it will obviously reduce the resale value - but not as much as putting black paint on it!).

Isn't there? I always have the beep turned off, but you do get the green hexagon focus confirmation. It's a useful check, but it's not very quick - I keep going past it, and going backwards and forwards to find it.

I have just put a focus screen with split image prism into my K100D, but I haven't used it enough yet to really say how much difference it makes.

I'm very happy with my 55-300mm. I was never that impressed with my 50-200mm - it never seemed very sharp - but some people seem to be, so there seems to be a bit of variation.

I haven't tried lunar photography with it, but even with a 300mm lens the moon doesn't look that big. You could probably get a reasonable result with a bit of cropping, but don't expect it to fill the frame.

I use quite a few old manual focus lenses - I'm not aware of any issue with dust. Obviously you wouldn't want to put something filthy on the front of your camera, but if it looks pretty clean then I don't see what the problem is.