Greetings! I recently noticed that I have very visible dust spots on my sensor. It becomes visible in pictures when using high apertures (eg, say f11 or above on a 40mm lens) and light subject matter. Luckily, this is not a common occurrence - I try to avoid going over f8. Nevertheless, just wondering if anyone has tried/recommends any of the sensor cleaning techniques? I've tried the easy stuff: air blast from hand pump, cycling camera on and off. Thanks!