filter conversion

[whardman]

Is it possible to get an adapter to convert a 49mm filter to a 55mm filter. I now there will be vignetting unless zoomed all the way in (18-55mm zoom lens). This is the only diffraction filter that I have found (that I can buy).
http://www.bhphotovideo.com/bnh/controller/home?O=productlist&A=details&Q=&sku=11556&is=REG&addedTroughType=categoryNavigation

 

[Johnboy2978]

If your lens accepts a 55mm filter and your filter is 49mm then you would need this (step down filter):
http://www.bhphotovideo.com/bnh/con...920&is=REG&addedTroughType=categoryNavigation
If your lens accepts a 49mm filter and your filter is 55mm then you would need this (step up filter):
http://www.bhphotovideo.com/bnh/con...636&is=REG&addedTroughType=categoryNavigation

There are probably cheaper ones...these are B+W. Ideally, you want your filters to be as large as your largest lens and use the step up filter rings to eliminate vignetting.