I'm using an ISCO Widescreen 2000 anamorphic adapter, with a lens mount that looks like it orginally connected the adapter to a small projector. This type of ISCO was marketed as a projector lens to mate with the Iscorama 36, 42, & 56mm 1.5x anamorphics. However, its actual squeeze factor is close to 1.4x and I use it as a 1.33x adapter (no harm in making the actors look a bit more slender ;-) I can use it with prime lens as wide as 28mm, but unlike the Iscorama's, the ISCO 2000 has no focus adjustment. To get in close with this lens, I have to use a +0.4 diopter in front, which I found on Ebay, along with a filter mount. As you can probably tell, anamorphics require quite a bit of ingenuity to make them work well in practice.