The Canon A710IS and the SD800IS are just about equal when talking about picture quality and picture sharpness.
Here is a link to a comparison in specifications:
http://www.dpreview.com/reviews/compare_post.asp?method=sidebyside&cameras=canon_a710is%2Ccanon_sd800is&show=all
There are a number of notable differences between the two cameras.
Cost - The SD800 will cost about $60 more.
Physical size - The A710 is larger
Battery type - The A710 uses AA alkaline or rechargeable NiMH & the SD800 has a rechargeable Lithium.
Optical Zoom - SD800 is 3.8X and A710 is 6X
Manual Controls - The A710 has Aperture Priority, Shutter Priority, Program AE and Full Manual - the SD800 does not.
Shutter lag - This is not shown in the chart but the SD800 shutter lag is 0.1 second & the A710 is 0.4 second,
You will be pleased with either camera.
Pick the one that has the features you want the most.
...........
A word about photographing fireworks.
I believe both of the cameras have a mode setting for fireworks.
But ..... there is more to it than that.
The fireworks mode uses a very slow shutter speed....which means you really need a tripod to get the best results.
I have taken fireworks with a 35 film SLR and you usually keep your shutter open for at least 5 to 15 seconds (sometimes much more) so that you have more fireworks in the sky. This also gives you streaks of light as rockets travel upward. And streaks from the explosions.
If you just take a 1/60th second picture of fireworks you will get sparse looking results.
You should not take a tripod to DisneyWorld as it is too troublesome to carry around.
Before the fireworks start....look around for a place where you can set the camera (fence, wall, etc). Some people carry a bean-bag for this purpose....so that they can set the camera at various angles.
If you do go to DisneyWorld, be sure and protect that camera from water when you go down the log flume ride. Carry a zip-lock bag.
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..
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Several years ago we decided to invest in a digital camera for our families trip to Disneyworld. We had already owned an older Pentax ME Super and Canon EOS Elan SLR but wanted something smaller for the trip. Since buying the digital our SLR's have collected dust. We are looking to replace our aging Sony DSC P52 camera which served us well over the last couple of years and would like some suggestions from those of you more familiar with whats on the market these days. Two products I have looked at are the Canon PowerShot A710 IS and Canon PowerShot SD800 IS. What's the general consensus on these two products? Are there better cameras in this price range?
Most of the pictures we take are family pictures; with most taken outdoors. We do take pictures of landscapes. Another nice feature would be to take pictures of fireworks.
All inputs/suggestions are greatly appreciated!
Thanks in advance!
Regards,
Tom in Connecticut
U.S. Navy (Retired)

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