Adapter for Nikon camera to fit Pentax lens?

I need to get an adapter so i can fit a standard Pentax lens for my Nikon D90, i live in the UK where can i get one? I need it by next friday!

The problem is, Nikon's flange to film plane distance is 1.04mm longer than Pentax's (46.5mm vs. 45.46mm).So, any Pentax lens that was adapted to fit on a Nikon mount would not be able to focus to infinity

Sorry, but you should have bought a K-x instead of the d90, and you wouldnt have had this problem, AND had a superior camera.

Doesn't exist I'm afraid. Firstly the PK and M42 mounts have a flange-focal distance of 45.46mm, and the Nikon F-mount has a FFD of 46.50mm. That means that if an adapter could adapt a PK lens to sit at 46.50mm, the lens would still not focus to infinity, and in order for it to focus to infinity you would have to mount the lens so it protrude into the camera body, this would probably result in the mirror hitting the back of the lens, which would be a really bad thing.

To make things worse the PK mount and the Nikon mount are roughly the same size, that means that you would have to mount that lens even further out, as a result the lens would near focus even more.

You could probably adapt an M42 mount lens to Nikon F, and there are adapters for it, but it's not the most elegant of solutions.

So you see because of the Nikon's long FFD you are pretty much limited to Nikon F-mount lenses, fortunately you do have a back catalog of up to the mid 80's to choose from, and older Nikkor lenses are easily convertable to the newer F-mount standard (that is pre AI lenses need to be AI'd)

And if you want to use older lenses, such as M42 and Contax/Yashica lenses then you are best off with either a FourThirds SLR or a Canon EOS.

You have made the move to Nikon and I think in the end you will be happy with that system. The D90 was way ahead of its time in the dSLR cameras and in many ways out performed it bigger brother, $1, 700 D300 (not that the D300 is not an exceptional camera, I use one when I need the extra reach the cropped sensor gives me)

You are starting to feel the financial crunch when moving from one camera system to another. Eventually you will have the lenses you want for your D90 and will have sold your fine Pentax lenses.

The next generation Nikon's cameras are just starting to appear and from the features on the entry level D3100, this should be a banner year.

Had you purchased the Pentax K-x, which is a very high performing dSLR, you would have had to use non-green AA batteries. With the Nikon D90, you are using state of the art Li-ion batteries, ones that should last you at least five years if you take proper care of them.

The first link is for a Pentax screw lens to fit on a Nikon body for £42 from a supplier in Dunstable. If you need an adaptor for a Pentax K bayonet lens, the same firm can make one, but it will be at leat double the price. I would try getting two adaptors - Pentax K-L39 and L39-Nikon, might be cheaper, certainly quicker. The supplier in Dunsatble will be able to help and advise.

I assume you realise that fitting the Pentax lens to the Nikon body means no autofocus and no focus beyond a few inches.