filters and varying lens sizes

[SierraBravo]

I have a 40D and three lenses in my bag (so far ) - the kit lens (17-85mm f4-5.6), a "magic drainpipe" (80-200mm f2.8) and a 50mm f1.8. The three take filter sizes of 67mm, 72mm and 52mm respectively.

I'm kind of hoping to economize on filters a bit and use step up or step down rings. As I am unfamiliar with these for the most part, which do you think would work best, buying smaller filters or larger filters with this range of lenses? I'm a bit lost here. Only filter I have thus far is a 67mm UV. I would rather buy one GREAT circ polarizer, for example, than economize and buy more than 1, if I could...

Thanks in advance. New to all this stuff and a bit confused, as usual.

Sarah

 

[HASHASHIN]

it's better to go big and step down.

 

[Big Mike]

Yes, it's much better to get a big filter and step down.

If you do it the other way, and use small filters, you will get vignetting or worse. Imagine a 52mm filter on a lens with a 72mm front :er:

 

[SierraBravo]

hey, thanks! I was thinking that might be the case. 72mm filters it is! Now to find the perfect circular polarizer...

 

[Sideburns]

hey, thanks! I was thinking that might be the case. 72mm filters it is! Now to find the perfect circular polarizer...

B+W MRC.

 

[SierraBravo]

Sideburns, that is what I have heard.