Step Down Rings

[Dmitri]

So I bought a step down ring yesterday from a local shop. 58mm -> 52mm. The problem is that it doesn't fit on my 50mm 1.8 (52mm).

Before I return it, anyone know what the problem is?

 

[Josh66]

Maybe you needed a step up ring? 52 -> 58?

I always forget which is which...

 

[kundalini]

Yes, you'd want a step up ring. Just remember that it's lens-to-filter for sizing.


EDIT:
You didn't actually say what you're after. Do you have a 58mm lens AND filter in which you are trying to use the same 58mm filter on the 52mm lens (and yes, I'm talking filter size, not focal length). Or is it reversed for some reason?

 

[Overread]

Far as I know
Step up - lets you mount a smaller sized filter onto a larger sized filter threaded lens - so say a 42mm onto a 50mm filter thread

Step down - lets you mount a larger sized filter onto a smaller sized filter threaded lens

So it should fit your lens - not sure why its not. Unless I have something wrong

 

[Dmitri]

I'm trying to fit a larger (58mm) filter onto the smaller lens (52mm).

 

[JeffieLove]

You need a step up ring 52-58 since the 50mm lens is a 52mm diameter and the filter is 58mm.

 

[KmH]

Yep, step-up 52mm lens to 58mm filter.

The first number is always the lens, and the second number is always the filter.

 

[Dmitri]

aaah crap. ok then, my mistake. hopefully he will exchange it for me. Thanks all

 

[Dmitri]

aha you were all right. I went there and exchanged it for 52 -> 58. I had it backwards. Thanks all