1.4x teleconverter

I am wondering if pentax make thes in an AF fitting so that i can use it on the istds? I can't find one on here, pentax uk, jessops or park cameras. Should i give up?
john

There is a 1.4x autofocus converter that enables manual focus lenses to be used as autofocus lenses on AF camera bodies. Don't see why you couldn't use that on the *istDS for the same purpose.

But on the subject of teleconverters, I have never been particularly impressed by the quality. They magnify the abberations of the lens and introduce defects of their own. I have tried 7 element converters, and still haven't been satisfied. I haven't tried a 1.4x converter, and I suppose that will give you the best chance of reasonable results as it is less extreme.

I'm only aware of the 1.7 AF adaptor. I think the Pentax 1.4 adaptors are MF only.

A 1.7 adaptor turns an inexpensive 200mm M lens into 340mm with limited AF. You have to pay a huge amount of money for a good 300mm lens, so whilst the adaptor may not be as good as the real thing, it's a fraction of the price, and the quality isn't too bad.

Quite right! My error, but the principle I think remains the same.

You're also right about relative costs, George. Personally I never have used telephotos over 150mm very much, it's just not my sort of photography.

I have the 1.7x AF adapter and can't fault it, particularly when used with a quality prime lens.

Hi,
I would back up what Kimbo says. The AF convertor is a very useful tool. I have always prefered prime lenses and generally find that the convertor with a Pentax prime gives better results than the equivalent zoom especially in the range over about 150mm. Also despite what Pentax says, it works very well with F4 lenses. Another advantage is that if you set the prime to close focus, you get a very good quality macro convertor!

Kim

And of course, with a 50mm lens, it provides a poor man's 85mm.

My converter arrived today, it's a Tamron 1.4x Pz-AF mount. I was told it was a PK-AF, but now find it isn't. It seems to connect up cleanly even with my old "A"lenses and focusses well with my autofocus lenses.
Should i be worried that it's Pz-AF?