Hey, Elizabeth. The #1 reason for grain (which is actually sensor noise)is that your ISO rating was very high. Now, in dark situations, that may be your only way to get the shot. In daylight, never.
With this much light, you can easily shoot at ISO 100 or 200, which has no noise. ISO 800 and higher introduces a noticeable amount of noise into your shot, but the good news is that there is an easy fix. While Photoshop and any pro image editing software does a pretty good job of reducing noise, there are programs that are written ONLY for noise reduction and they do a fantastic job of it. I would say the top two are Noise Ninja and Neat Image. I use Neat Image, and they have a free version. I was so impressed that I upgraded to the paid version, Neat Image +.
Here is a quick pass of your shot through Neat Image. Note the fuzzy bricks at top and bottom, which is one of the dangers of any of these programs: going too far can make your image noise-free, but muddy.
In summary: When shooting in the day, make sure you have dialed down to ISO 200, and this won't even be an issue. ;)
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{K:88111} 6/14/2008
