Stacking fllters? on Canon:- 10-22 and 15-85

[mipevo6]

Folks,

I am considering buying a 10 stop B&W screw in type filter.

I have 2 main lenses I might want to use it on.

• Canon 10-22 - 77mm thread
• Canon 15-85 - 72mm thread

I have 2 main questions:-

1. Does anybody know if it will vignette on the 10-22?
2. Could I get a 72-77 step up ring and also mount it on the 15-85, but would it vignette?

Anybody tried either of these combinations?.

A £10 step up ring is much cheaper than having 2 10 stoppers

Thanks in advance

 

[mipevo6]

anybody?

 

[HoppyUK]

No problem.

That's not stacking filters one on top of another, that's just using a stepping ring to fit a larger filter on to a smaller lens - common practise