I have a Canon Powershot A75 (I believe the A510 is the next generation of that same model) that I used at my last trip to Disneyland. I am generally pleased with the pictures that I took with it. I had just gotten the camera a couple of weeks before going to DL, and I must say that was the biggest mistake.
Try and get your new camera as far in advance of your trip as possible. This way, you can get familiar with the camera before hitting the big vacation time. My evening and inside pictures are where I was most disappointed. If I would have read more tips and played with the "manual" modes of the camera I think I would have had much better results.
Now that it's a year later, I have now made the plunge into an SLR Digital Camera, replacing my old Film cameras almost totally now. I bought a black model of the Canon EOS Digital Rebel (non -XT). I have had much more experience playing with it, and I hope to get some really good pictures this trip to WDW in a couple of weeks
One of the big tips that I have is, especially for the Canon A75 that I have, make sure to have enough batteries. I use 2 sets of rechargeable batteries for my setup (I like the Canon A series, they use AA batteries.) From experience, one set doesn't get me through an entire day of heavy shooting. The other nice thing about using a standard battrery, almost anywhere you can find AA batteries on sale if you should go thourough all of your charged up batteries.
The next tip is that this is digital media. If you have the room, take ALOT more pictures that you might have with a film camera. My single day at Disneyland/California Adventure last December, I eneded up taking 172 pictures! Sure, not all of them were spectacular, but they didn't need to be. I now have a much more memorable trip, since I was able to take so many snapshots.
Another tip that I'll give out, is instead of buying as large of a memory card as you can, consider buying 2 smaller ones instead (ie. Instead of 1 1GIG, buy 2 512k). These ARE electronic media, and things CAN go wrong (unfortunately). So if one card decides to hiccup on you, you have another readily on hand.
Lastly, have some way of Archiving the pictures as soon as possible. I have a laptop and a mini-card reader that I copy all my pictures each night to the laptop with. My new solution is much more portable. I have a 4th Gen iPOD, with a camera connector. I have used this solution once, this past summer at Washington DC. It is a nice little backup tool that I can have with me in my camera case. It worked well with both of my Canon digital cameras, and I was even able to view a small slideshow of the pictures right after they downloaded.
I think I have rambled on quite a bit more than I thought I would
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I hope anyone that reads this will get some handy tips out of it
