http://www.pentax.jp/english/support/digital/k-5_s.html

Explicitly states that it improves low light AF!

One can only hope this is true:

http://forums.dpreview.com/forums/readflat.asp?forum=1036&message=37920937&chang...

Well, arseholes!

I finally got round to checking the replacement K-5 tonight, and.... it's got a problem.

It focusses great in good light, focusses great in all light oudoors, and even focusses well in darkness if the AF beam comes on. It focusses great by live view in all lights,too.

Under dim tungsten light and focussing by the viewfinder it focusses in front of the target. At f/1.4 - f/3.5 it's enough to leave the subject completely out of focus.

I've a K10D Grand Prix Edition (includes grip) which you can have for £280.

My replacement arrived today.

I've just done some very quick testing, and it appears to be a lot better than the first one, if not suffering no FF at all at f/1.7 in low tungsten light.

I'll do some more testing tomorrow, but my instinctive advice, based on a sample size of 1, would be to send them back for exchange.

I've just got off the phone to Park.
They're exchanging mine, with no argument.

Hopefully number 2 will not have the problem.

I've just got off the phone to Park.
They're exchanging mine, with no argument.

Hopefully number 2 will not have the problem.

Excellent!

---What respective EV values are your two shots of the pentax box ...


---This will help you work it out ...

I'll have a look at that over the weekend, and do some more testing; I'm not familiar with using EVs, tbh.

I set the dimmer for the second shot so the room was just bright enough for the AF Light not to shine, if that's any help. The first shot was about 2 stops brighter.

It was your post on my 'Put my mind at rest' thread that led me to reading about the issue in the first place, btw. Thanks.

(I got mine from Park Cameras, so assume they'll 'do the right thing', whatever that turns out to be.)

I wasn't exactly giving the shot much thought.

I quickly set it up having read about this on the other channel, fully expecting there to be no problem at all.

Have you done anything about it, e.g. contacted your dealer?