[joshman (Josh)]

ok, so i need a bit of a run down on the various filters available and what i've seen used, starting with the filter on the canon sensor in your typical DSLR. what is it? what does it allow and block?

then can some please explain the difference between the H-alpha and H-beta filters, in terms of what they allow and not allow, as well as the good ol' IR/UV filters?

and as for modding the canon DSLR, what exactly do they do to the filter in front of the sensor?

sorry if a sound high strung, but i'm soncufsed!!! and unable to spell apparently...