V35 Project Sigmas Vs Sigma Cine/Classic 

I have Classics and they are the same optical formula as the the Cines so they are and f/1.4. You just lost so much light due to all of the internal reflections. One thing this also creates is quite a heavy vignette with a noticeable amount more light transmission in the center of the image and a general color wash that can occur if there is a bright saturated color entering the frame. They are quite fun to play with.

Thanks Casey!

yea Casey hit it on the head.