I have the Tamron 1.4 Pz AF MC4. AF is not too bad on non SDM lenses. It does try to AF with an SDM lens but only succeeds one in about four times and that is with a static subject.

I had a quite expensive pattern grip on my Canon and basically it worked OK except that it kept coming loose and losing battery contact.

I now have the genuine one.

I have always had the genuine one on my K20.

Still on offer from SRS at £639.

That makes two of us (or in the case of my K20, a £600 one).

Er when did it cost £1069 George?

How would Pentax know whether there would be a market for longer lenses when they don't make any.

Not only could I not buy a lens from them which was suitable for what I wanted, it also meant I could not buy a K5 to mount it on. I had to buy a 7D because that was the best body on which to use the 100-400.

No - never had any trouble with mine. I was just trying to work out where the problem is. If the switch was duff, you probably wouldn't get the AF-S. As it is, the fault is probably with the autofocus system itself.

The only thing I can suggest is cleaning the contacts on the lens mount on your camera. A dry tissue should do.

Do you still get the green "AF-S" at the top of the screen when you switch the camera on?

I am surprised to hear you say that Tony. I was always told that in cooking as in computing, "Garbage in = garbage out".

One of my real disappointments was a bottle of Champagne which I acquired on Concord ( ) in 1982 and placed in the back of the cupboard for a special occasion. It should have been about £100 at the time and was vintage.

In 1994 I came home on holiday with the person who was to become Mrs Oggy and the time to open it seemed to have come. It was duly chilled and served and there was a definite hint of Sarson's to it.

Just had a look at the K-x destructions and it doesn't seem to specify voltage for an AC supply. Unlike other Pentax(e)s (Pantaces?) the input is connected directly to the battery terminals. The batteries are going to produce 4.8-6V.

That LM1084 looks a useful bit of kit. We tend to be stuck with 78s or 317s at work. TBH, with the silly price of pre-built units I wouldn't bother building one.

For those who are wondering about the smoke of which we speak, it is smoke that makes electric things work.

Don't believe me? What happens when the smoke leaks out? It stops working.

8V might be a bit high. The batteries are going to be a maximum of 6V. Remember having let the smoke out, how hard it is to get it back in.