Mine took more than two weeks to come back too. Pentax replaced the sensor and had to wait for parts to arrive. Seems to be perfect now. Went to Kew on Sunday and took a load of shots (mainly macro - Sigma 70-300) and they look stunning. Exposure seems to be more accurate too. The camera came back to me with firmware 1.01 (it had been 1.00) and I've upgraded to 1.03 - and the shake reduction may even have improved a little - although it was pretty good anyway.

I've just left my K20D in to be repaired for the banding problem.

I shot 112 photos with it last Thursday, more than half of which had vertical banding - in most of them I can see the banding even at thumbnail size, and all of them at fit to screen (35% for landscape). It was a nice day, about 10 degrees C, some shots were auto, some aperture priority, all using 18-55mm lens, some were very high contrast shots, others low contrast. Some that had banding were shot seconds before or after others without banding. All were JPEG (I only had one 2GB card with me so I switched off RAW, but on a previous day about a quarter of all my shots (RAW+JPEG) had banding - that day temperatures were about zero to 2C - although the previous night, in -3C there had been no banding). I have only shot 278 shots since we bought the K20D, so about a third of the total have had banding.

The retailer (a Pentax pro dealer) said he hadn't heard of the problem before.

(Image link - crop showing banding effect - click link and view full size - I did try adding it here, but it displayed full size, which was a little large... And when I added a pic to the gallery on this forum it didn't display full size, so you couldn't see what the fuss was about - the banding seems to be visible at certain resolutions and not others)

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