Hi guys, want to say first that this forum is really great. Lots of friendly people and good info. So, I've got a cheap EOS to NEX adapter without an aperture ring, if I buy the Sigma 10-20 Canon mount, how does the Aperture work? I have a Canon 50 1.8 that I set the Aperture down to 1.8 in my Canon EOS body and leave it at that. How does it work on a zoom lens? *I tried testing it out with my 18-55 kit lens, setting it to 3.5 in my EOS body and as I zoom in the exposure doesn't change. Does that mean the Aperture is fixed at 3.5 all the way through the focal range? What can I do without buying another adapter with an aperture ring? I suppose I'll have to look into that. I'm just curious as to the inner workings of the camera and lenses in this situation. Thanks for any info.