That's an obvious question... In order to find out, I have made many hundreds of photographs over the last few years of different objects and under different circumstances. Here are some examples of rain, snow, fog, insects and even a small bat. The huge differences compared to the balls of light speak for themselves...
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rain |
rain close-up |
rain close-up |
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snow |
snow close-up |
rain close-up |
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fog |
thick fog |
thick fog close-up |
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insect |
insects |
insect |
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insect |
insect |
bat |
Note: you might find it weird that some of the rain drops seems to be falling 'upward', but this is simply caused by the flash. The upper part of the rain drop (the first part that is exposed) is exposed most intensely; the lower part becomes blurred...
to Light Phenomena