Deleted my comment because I wanted to add something that takes some time and Gary seems to be very fast and I aint so fast

John that's the problem since for example a pixel under a red filter only gets red light so it measure the brightness of the redlight... what if the light is green that wont go through the red filter.

It's like shooting with coloured filters with a B&W film, according what you just said it does not matter if you use a green, blue or red filter, they would all produce the same photo but we know that isn't true right.

So if you want to get the whole picture like shooting a B&W without any filter (maybe white balance filter) you should remove the colour filter infront of the sensor or do what's done as shooting in colour with a digital sensor by simply using the information from the pixels around the pixel in question and create an approximate pixel with the right colour and brightness value.
For B&W we could throw away the colour value but still the processing is the same.

Better go for the K100D super for compatibly reasons of newer lenses.
SDM and HSM is starting to be more common and the K100D does not support those.

Great they have that I was however wondering if people 15 to 10 years ago also needed a 600mm f/4 lens or something like that, I know many brands have such a lens, even pentax but how many are sold of those lenses?
I beleive the majorty was happy with a 400mm lens or am I wrong about that?

Because the colour filter is physically in front of the sensor so how do you want to ignore that, the only way to do that is by removing it.

Yes correct and the sensor would have more resolving power as well.

That's not true though since you can't remove the colour filter so you're still stuck with processing it in blocks of 4.

YOu can of course maybe say to use the red filtered pixels only to create the effect of shooting B&W through a red filter but that would mean only using 1/4th of the pixels

Don't get me wrong, I was only trying to say that with a fullframe you should need longer lenses to get the result you're looking for.

The DA*60-250 for example is a 90-380 equivalent for 135film size so if you aren't ready to "digital zoom" a little bit I don't think you would notice a lot of difference in the amount of zoom compared to the 200-400 on 135 film.

And why is everyone so sad that Pentax does not offer such long lenses, 300mm is still 450 equivalent focal length on 135film and I believe that was a pretty long focal length 10 years ago or not?

The OP didn't said something about new technology only about a new generation of sensors which are interchangeable.

Or was the comment meant for jon.dc?

You're right about that but Greynolds wants to have the subject appear larger relative to the pixelsize I believe.

So you're going to rent a 500mm or 600mm ?
Or else you can do with a lower pixel count Pentax camera with a 300mm

Nothing to attack anyone but I would like you to think