Learning curve???
http://www.amazon.co.uk/Pentax-K10D-Magic-Lantern-Guides/dp/160059185X
Goes further than the K10D manual and explains more about why the different modes are available and when to use them.
My Names Alan, and I'm a lensaholic.
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Take the same photo over and over and change the aperture values so you can see the effect it's having. Now do it again and this time change the ISO settings between shots and see the difference this makes. Get comfortable with using different apertures and ISO's first - it'll be a good start.

Joining the Q
Try using f8 in AV to start with. If you want more things in front and behind the thing you are actually focusing on to be in focus then go to f11 or f16.
If you want only the one thing you are focusing on to be sharp and everything else to be a bit blurred go to f5.6 or lower.
AV ( aperture priority) will teach you a lot about depth of field if you take lots of shots of the same subject at different f values.
If you like try taking a series of shots of the same subject starting at the lowest f value of the lens on the camera (say f4.5) and work up to f22 and look at the difference.Pick a subject with things in front and behind of the main item you are focusing on.
K100D Super, 18-55, 50-200, Sigma 10-20, Sigma 70mm macro and lots of old lenses
To simplify (to over simplify really, but it's a start): Select a large aperture (small f number) when you want to minimise depth of field (the amount that is in focus), or when the light is low (to hopefully get a reasonably fast shutter speed). Select a smaller aperture to increase depth of field, but don't go very much further than necessary. Select something in between when depth of field is not crucial. Lenses often perform best at around F8, though it depends on the lens.
If after taking a picture, if the exposure is under or over what you wanted, dial in some +/- Ev compensation and try again.
Also be aware of the ISO setting. Either leave it on Auto or set according to the light level.
I strongly suggest getting a book on photography to learn about the affects of aperture and shutter speed (and much more). I have one that I no longer want. I'll put an ad in the Classifieds section.
~Pete


K10 d-18-55mm
Tamron 70-300mm
The purpose of life is to live a life of purpose..
Kal 10 d
Member
K10 d-18-55mm
Tamron 70-300mm
The purpose of life is to live a life of purpose..