I haven't posted here for some time but there is a little issue I'm scratching my head about, I wonder if anyone has had similar experience or could enlighten me? I recently bought a Sigma EX 17-50mm f/2.8 secondhand from a well known dealer in Scotland, almost mint condition and it's a very nice lens. However, the image review on my K5 takes several times as long to appear after taking a shot with this lens as it does with my other Pentax lenses, and Sigma's own EX 100-300mm f/4, which are all pretty snappy. It's as if the camera is writing a massive file to the card or clearing a lot of something from the buffer. The file sizes are perfectly normal, but the review delay can be quite annoying. I'm shooting in single shot jpeg... Any ideas?