Hi TFM, I've been enjoying your content for years.
I'm in kind of the same boat, never owned a camera before that didn't come with its only lens attached. Well technically, I still don't (and probably wouldn't for stills unless/until my trusty WB850F dies). I was likely the very last kickstarter and am still a few weeks away from receiving my Chronos, from the sound of things. That hasn't stopped me from researching and shopping though. I've taken the plunge on a Schneider Variogon 18-90mm f/2 from ebay and have already received a Belle & Howe Angenieux 25mm f/0.95 from Victoria Camera Traders (great guys and fast service there, btw). Neither broke the bank, with both priced about the same as a new sample of the computar 12.5-75mm. I'll hope the CS-C adapter I plan to get with my Chronos backsaces them properly, but we'll have to wait and see.
I was aiming to find lenses meant for 16mm and super-16. The frame size of 16mm film is almost a match to the 2/3" sensor on the Chronos so there should be no vignetting and only a minimal cropping factor (a 50mm focal length lens for 16mm film frame should produce an image like a 58mm focal length lens on a 2/3" sensor). Super-16 is pretty reasonable as well (a 50mm would behave like a 66mm). Some good info is
here and
here. I've been trying to think about the physics of it and while I think I kind of understand how the mismatch alters the field depth to behave like a different f-stop, I am inclined to believe this wouldn't have much impact on the light gathering performance. (if a 4/3" 50 mm f/2 lens is on a 2/3" sensor, we can expect it produce an image framed like 100 mm lens with the field depth of an f/4 aperture but I *think* it would provide the same contrast and brightness as though it were still on a 4/3" sensor at f/2. If anyone knows better, please, by all means, correct me.
) I've also noticed there's quite a bit of interest for vintage lenses in the Blackmagic Pocket Cinema Camera communities... its sensor is between 16mm and super-16 so their findings are quite valuable to us, as well.
Anyway, thanks for all the entertainment over the years. That headspinning Chakotay still has my mind reeling like a block of clay after a silly putty slug. Once my camera is in, if you ever want a second angle, I'd be willing to make the drive from OC up your neck of the woods. Might give me the impetus to finally get my BFR45-70 fixed (or just say screw it and haul up the 460 instead)