SLR camera not expensive and i can change the lens and also there is filter to clean the photo with high resolution and the MP is high but the camera not big size its easy to carry when i travel , i liked this sony A99 but its so expensive .
I hate answering question in this section the photography section of yahoo-answers is the worst and rudest.
I've owned them all. They're all great camera's. The thing you want to keep in mind when doing your research is not so much the camera or brand but;
Sensor size 35mm (full frame) or Cmos The camera itself is not the investment but the glass (lens). The glass will outlast any camera you buy both in longevity and technology.
Lens are the major investment not the camera. Myself, I'm currently hooked on Sony (I like cutting edge), but Cannon and Nikon are also excellent and outstanding brands
Once you invest in lens; that's your brand!
No camera will take great pictures as well as a light savvy, smart, educated (in that order)photographer.
You've got quite a wish list for "not expensive". You actually expect to get all that technology for "not expensive". You're dreaming and I think you know it.
Besides there aren't many slr cameras in the market these days because they use film and as we all should know by now, film is on it's way out. There are however many dslr cameras on the market, these are digital and don't require film.
But I can tell you this. A basic dslr camera, I do mean basic, $500 - the Canon t3 (1100D). This is "not expensive" by dslr standards. Expensive... well professional cameras start at $4,000 or so.
All dSLR's are good. They are all basically the same.
Filters block light not clean the photo. All dSLR's have interchangeable lenses. The more megapixels, the higher the resolution. That's just picture size not picture quality. All dSLR's are bulky. Most people don't find them easy to carry around.
The Sony a99 is not a dSLR. It's an SLT. DSLR's start at around $500. To mere mortals like me, that's expensive.