Panasonic ZS15

Panasonic has updated last years ZS10 and has improved the low light ability.
They did this by lowering the megapixels (14mp to 12mp).
Once again proving that 14mp and 16mp sensors are just too noisy for small cameras.

The ZS15 is as good as it gets for small big-zoom cameras.
Picture quality is very good.

It also has the important manual controls you want for tennis.

Here is a recent review:

http://www.steves-digicams.com/camera-reviews/panasonic/lumix-dmc-zs15/panasonic-lumix-dmc-zs15-review.html

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