Hmm! A rather basic sounding problem!!! I tried to rustle up a few reasons, but...?
Starting from scratch, some Qs:
1. How are you trying to take these pictures? - Some camera settings, perhaps.
2. Are you focusing manually, or using AF?
3. Is the viewfinder dioptre adjustment correct for your eyes? (But then did you use Live View?)
4. Is the angle you have the camera set very different from that of your eyes when looking at the web?
(Sometimes light does not reflect through too much of an angle.)
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