sramesh21, I'd defintely go with a good set of high capacity Ni-MH Rechargeable batteries.
PowerShot SX100 IS
1. AA-size Alkaline Battery (x2)
2. Rechargeable AA-size Ni-MH Battery (x2)
3. AC Adapter Kit ACK800 (optional)
Still Image: approx. 140 shots (AA-size Alkaline Battery), approx. 400 shots (AA-size Ni-MH Battery) *
Approx. 420 min. (AA-size Alkaline Battery), approx. 600 min. (AA-size Ni-MH Battery)
* LCD screen on. The above figures comply with CIPA testing standards and apply when fully-charged batteries are used.
its been specified that i should use the alkaline batteries .I am planning to buy rechargeable batteries . please suggest which batteries to buy .
thanks in advance .