16:9 Adapters

[Matt Serrins]

I'm looking into 16:9 adapters for both my video camera (dvx 100) and also maybe my bolex with switar primes (since most of my film ends up telecined anyway), but I don't really understand the difference between some of the adapters on B&H, for example. There is a $1300 century optics which is fully focusable, a $700 that is not, and a $300 that is not (and also has a small rear element, which may be limiting for video lens i.e. vignetting.) How does the focusability affect the use of these lens, on both a video camera and on the switar primes ( i know i'll need some sort of stepping contraption for the bolex). Is there an advantage to having a 16:9 lens that focuses? Does using a prime lens change the equation? Thanks for any advice.

 

Matt