Thanks everyone for the quick responses! I'm not sure why I didn't realize that being in M mode meant i had full control... Call it a brain fart, if you will. In fact, I even went back to the store and showed them the 'issue', and they were equally perturbed by it. I was sure I'd altered the exposure compensation while in manual on my k20d, although I only owned that for a couple of weeks so maybe i'm remembering everything incorrectly today.
Anyhow, it's good to know it's not a problem with the camera. Thanks very much to TomTextura too, for the additional coaching on the EV scale - I'll be sure to test this all out tomorrow first thing! I'm hoping the difference in exposure of the images when viewed on the LCD screen vs. the computer (where they're consistently underexposed) is something that will be remedied as well.
However, not to bring up an entirely different issue, but the camera has started making a very loud noise when turned on, almost like an electronic scratching noise, or like a needle sliding across a vinyl record, which it didn't do the first 2 weeks or so... Does everyone else have this as well?
Thank you again for all your kind and quick responses! They were definitely reassuring, and made my heart rate slow a little bit. I was in panic mode for the better part of the day (quite unnecessarily, obviously!
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