>>4384719You did not bad. You got at least $400 worth of filters for 15 bucks. That said, only 3 of them are useful for digital.
The most useful filters are probably the Skybolt polarizing filter (to get rid of reflections) and the ND filters.
The +4 filter is good for super macro photos. But in reality a +2 is more useful for general purpose to get a little bit closer to subjects. +4 = super macro.
The fog / diffuser / star eight / CS filters are sometimes ok as effects filters. More often these filters are used by pro video shooters rather than photographers.
The rest of the filters are pretty much for shooting on film. With the red filters being used for black and white film photography, which produces a really good in camera look.
Personally these all are a waste of money as the only filters that interest me are 77mm or 82mm filters. If you buy smaller filters you always end up having to buy more and more filters every time you get a larger diameter lens. It's much better to just get one larger diameter filter then adapt it to all your lenses.