Default value for skipping frames is too low to adjust lighting

[Sonix]

At least on my Macbook Pro, using sightsnap with the default values (and by extension via the git commit hook) produces far too dark images. setting the frameskip to at least 3 (better: 4) fixes it by giving the camera enough time to adjust.

(On a Retina Macbook Pro 15' Late 2013)