Also, while silicon solar cells do not need direct sunlight to work, they will collect a lot less energy indoors or on a cloudy day.

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We think the results are very respectable, with decent color contrast (filming was on a cloudy day) and no rolling shutter effect (which can often be a problem).

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The center court stands were half-empty on a cloudy, mild day for Azarenka's match.

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It did, however, deliver a brighter picture on the cloudy day we tested.

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