Excuse me but, whilst I agree that Matt is wonderful, check out this thread . . . from 4 years earlier.

Anybody who has half a notion to buy one of these should do it now. The HSM version which replaces it will be significantly more expensive at $969.00. And for macro work, AF can be more of a hindrance than a help.

£399.00 new from SRS, £250.00 used here. A no brainer really.

If I didn't already have 2 x 100mm macro lenses, I'd have it like a shot.

I've tested my Kenko tubes (labelled: KENKO EXTENSION TUBE FOR P/AF, which is a bit of a misnoma because they lack both SDM contacts and the AF screw) as per Matt's configuration, but only with the DA* 16-50mm lens.

They behave exactly as Matt has described, identically to his Teleplus tubes.

I've not gone any further with this because my macro lenses, which is what I would use anyway, perform as expected and give me focus confirmation when the body is in MF mode.

It shouldn't be beyond Pentax's expertise to allow us to choose which AF drive method we prefer, especially when some DA* lenses have both SDM & screw methods for focussing.

It'd be interesting to know what happens when a pre-SDM body is used. I guess it'll work fine.

I have some Kenko tubes that have the contacts. I'll give them a try. From what you describe, I'd say it was a tolerence issue between the spacings/height/depth of the contacts.

Which particular lens were you using Matt?

Welcome to the form Brian.

Perhaps one of the first things you may need to do is update your new camera to the latest firmware for that model.

You'll find all that you need here.

I think you just did.

Re: DA* lenses and SDM motors. My first 2 x DA*16-50mm lenses both developed focussing issues. Wouldn't lock, or when they did lock, the image was not in focus. They were early batch models. My third, I've had for a 2-3 years, and no real issues that I couldn't put down to 'operator error'. The duffers were replaced under warranty by that well known toy store in Watford High Street.

The DA* 50-135mm has never skipped a beat. Both are brilliant lenses producing superb results.

You'd get more meaningful information by posing this question in it's own thread, with a Poll.

Not so cheap when you've added delivery & customs charges, and VAT.