Metering works fine on my Kenko tubes, and the Jessops set that ChrisA mentions. The Jessops tubes do need the mod for the 7th pin though.
Chris, thanks for the credit . . . again

I think any tubes will do as long as they have the requisite number of electrical pass-through contacts to convey lens info to camera and vice-versa. Some have even been known to use multiple sets to achieve astronomical magnification. Having ample light of course, is a must.

I have a set of Kenko tubes. They have an AF suffix and claim to be AF tubes. This apparantly means that they can be used with MF & AF lenses, but in manual focus mode only.

Manual focus is no big deal when shooting macro, in fact, I and many others prefer it.

Good grief, if only I'd known it was really that simple

I think it's well documented here that the Pentax DA/Samsung D-Xenon 50-200mm is an very good performer and good value. Have a look at one in a store and you'll be surprised how tiny and light it is. I've been amazed at some of the images I have taken with it. Curry's have had it listed at £29.97 but I'll doubt you'll find a store that has stock. Jacobs were selling it for £49.99, then £99.99, now £149.99. Chris at SRS might do you a deal on the Pentax DA lens, he has it listed at £169. You'll only be missing the 45-50mm range which is completely inconsequential I think.

I am very surprised that there is so much vignetting wide open.

Q: Did you have the lens hood on, and is it any better with it off?

This is a DA* lens after all. Makes me wonder whether I actually want one. Chris (SRS) says his are on their way from Belgium and I've pre-ordered one, but . . . I'm not sure I like this. What's the point of owning an expensive lens if its not good wide open?

Q: What focal length was this image taken at?

If it's there at f2.8, it'll still be there at smaller apertures, but to a lesser extent.

It could be my screen but the images of the Balsamic Vinegar bottle appear to have vertical stripes, but only in the DA* 50-135mm shots.

I'm impressed, well done. The 50-200mm is a super lens. I have the Samsung badged version, £50'ish from Jacobs. I used it almost exclusively on a recent trip to Whipsnade Animal Park. My other lens was a 16-50 DA* . . . which stayed in the bag most of the time.
EDIT: The Samsung lens is now listed at £149.99 on Jacobs web site.

You are very lucky to have a live-in model. The first pic, has it been processed at all?. It looks washed out to me, skin tones are not natural. The other two pics look very good.
The church shot is not straight and could do with a little anticlockwise rotation. Look at the two chandeliers. The one on the right is almost vertical, the one on the left is not.

In reply to another thread, I think George mentioned he was going to be away until Sunday . . .

Thanks for the info.