Originally posted by Abstract How am I funny? For thinking that a enthusiast model would perform better iso wise then a beginner? If so I am hilarious...
Honestly at this point it seems like a fanboy getting angry, I am comparing cameras to get the best deal, I have no brand loyalty, point is K-7 has been put up against models such as the D300 and Canon Equivalent. It has not been compared with beginner models.
Sensor quality has a small part to play in the overall "enthusiast package". Pros can take breathtaking shots with rather old sensors, and tend to stay below certain ISO limits anyways. With the exception of the fullframe / ASP-C comparison, I think sensor quality is mattering less and less in comparison with other features that are valuable to pros.
Weather-resistance, metering, AF speed AND accuracy, external control (without a menu) of a wide variety of features, and frame rate matter just as much as ISO to a working pro who needs the perfect shot to make money. Look in National Geographic, utilizing some of the best working photographers in the world, to see what I mean. Some very powerful photos have their fair share of grain, but they are expertly composed, perfectly focused, and capture the perfect moment in time to tell a story.
I should mention an alternative you have not thought of, but might be a good place for you to start. I bought the K20d for a very good deal, because it was "old tech". However, sensor quality aside (it has a very good, but not anywhere close to the best, sensor) the K20d helps me produce good photos because of the great variety of buttons on the outside of the camera which help me work fast. I tend to buy manual focus and will concede that AF is not it's strong point, but it hardly holds me back since I have learned how to manual focus. The camera is also extremely robust and I have every confidence in its performance .
If you don't need a modest AF performance increase and video, the K20d can be found for less than a k-x these days.