Quote Originally Posted by Gerald Koch
Step up rings are made for changes of a few millimeters say 49 mm to 52 mm.
I have a step down ring for 72-52 that I bought from camerafilters.com.

But I am not averse to using multiple step up rings if I can find any in the right size.

Quote Originally Posted by Dan Fromm
Anupam, do it in several steps. That's what I do, and what I do you can do too.

Give up on the Wolly and look for a 25/1.9 Cine Ektar II. At f/2.8 and above 10:1, my 25/1.9 CE II beat my and Charlie Barringer's 25/3.5 Luminars wide open.
Dan, I am just trying out the Wollensak because I picked it up really cheap. I'm looking out for the Ektar and will get one if I find a good price.

Where do you get your extension rings from. Most of the ones I see online are for common 35mm sizes approx 40mm upward to 80 and more. If I could get a set of step ups that go from about 20mm all the way upto 52mm, it would make life much simpler in terms of trying out odd lenses reversed!