I bought a CY lens adapter for my yashica 58mm f=135mm lens & that's attached to an anamorphic lens clamp but I'm having trouble choosing which anamorphic lens to buy off eBay?? Thought Schneider 2x cinelux would be a good cheap go to but don't like the idea of having an adjust knob right in front of the lens! So it's between a Isco 60mm or Sankor 16? Which one should I consider buying??