Originally posted by Vantage-Point Nothing is wrong with the K-3 form factor. All I was saying is a Dslr with a smaller form factor that was capable of shooting at high isos with minimal loss of IQ and better dynamic range than the K-3, K-5 series cameras would be a good option to have. A good camera for a wedding shooter who is already carrying a lot of stuff so a lighter but capable camera(s) would probably be appreciated.
There is basically no difference in IQ between K5 and K3 series cameras.
Compare at each ISO and you will see that they are within a few 1/10 stop on DR and noise at each ISO.
The biggest difference between them is that K5 has ISO80 available which give it a small advantage over K3 at ISO100.
If you want better IQ than on K3 II, you need to go for FF, but then the size/weight of the camera will increase.