[vlad]

Indoors, I always use a fat 50 mm lens. f/1.8 or, better, f/1.4. My Pentax camera has a pretty good sensor, I can bump up the ISO to 1600 with almost no penalty on the quality. A 1.4 lens is 4 times faster then your current 2.8 lens. That could mean a reasonable ISO of 800 instead of the grainier 3200.