Gels, bellows, gobo, flag, bellows (non-tapered)?

A howp oor cale wi the EOS50 kens aboot aw this, cos a din'nae, ye mey as weel be bletherin dooble dutch as faur as I'm concernt.

Oh aye, the Tiffen is a little bulkier, so perhaps go for the basic Hoyas, B+W's or Koods. And look for secondhand stuff.