Alright, as the title says, I'm taking a three-week river trip on the colorado river this summer. I am taking my camera with me. I'm worried about two things: Battery life, and memory Battery Life: The d50 has a notoriously long battery life using the EN-EL3 but three weeks is pushing it. I'm expecting to be taking a lot of pictures daily. The issue is that over these three weeks, I will have virtually no access to electricity to charge the battery with. So, i run into a problem. Can you replace the EN-EL3 with standard batteries? Granted, it would resort in shorter battery life, but I can take batteries with me plus i don't want to spend a lot on EN-EL3's. A charger for the EN-EL3 does me no good even though i can bring it with me. Memory: The 512 MB SD card I have now will allow me to take about 300 pictures. I'm planning to take a whole lot more than that and need a way to store them. I was looking at some one-touch backup systems such as these: http://www.ritzcamera.com/product/PH800110.htm http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=1631914&CatId=0 http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=2145254&CatId=1203 which, while expensive, are cheaper per gigabyte than buying SD cards totalling any similar capacity. Do you have any recommendations? If you know of one that uses standard, replacable batteries instead of an internal, rechargeable one, that is preferable. Thanks. I'm really looking forward to this trip. I hope my camera is too.