K30 Comparison batteries & No.of shots

Depends on what type of AA cell you are using. Super Heavy Duty - terrible in a camera, great for TV remote. Alkaline, okay in a camera if you don't use flash, LCD, live view, long exposures, or other high current draw functions. Best AA cell is probably LiFeS2 (energizer ultimate lithium, disposable) for longevity in cameras. I remember shooting 1500 shots through my K-2000 with those. They also work great over temperature and are very light weight.

edit: Those are your disposable options, you also have rechargeable. NiMH, NiCd, NiZn. I would avoid the NiZn as they have low internal resistance and high terminal voltage (and accordingly high load voltage) which some devices won't tolerate (i.e. I toasted a flash with them once). NiMh is probably the way to go. Normally the lower the mAh rating, the longer the shelf life. 2000 to 2100 mAh seems pretty good, especially the Sanyo cells. As you get up to 2500 mAh, they usually have a shorter shelf life (good for shooting lots of shots at one time like a wedding, not good for shooting a few hundred shots a month). /edit

I imagine the standard Li-Ion rechargeable will work the best if you shoot a lot of shots in a short time period (like a wedding). The LiFeS2 disposable AA cells might be the way to go if you don't shoot frequently and want your battery to always be charged. They have a shelf life of like 10 years or more. The Li-Ion will lose much of its charge in a few months of non use.

Really depends on what your shooting style is, as that will depend on how long your AA battery or Li-Ion battery will last.  Honestly, I would shoot Li-Ion unless you have some special need to shoot AA (availability, etc).

Eric

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