This is the main camera used in the film Barry Lyndon

Kubrick was "determined not to reproduce the set-bound, artificially lit look of other costume dramas from that time."
After "tinker[ing] with different combinations of lenses and film stock," the production got hold of three super-fast 50mm lenses (Carl Zeiss Planar 50mm f/0.7)
developed by Zeiss for use by NASA in the Apollo moon landings," which Kubrick had discovered in his search for low-light solutions.
These super-fast lenses "with their huge aperture (the film actually features the lowest f-stop in film history) and fixed focal length" were problematic to mount,
and were extensively modified into three versions by Cinema Products Corp. for Kubrick so to gain a wider angle of view, with input from optics expert Richard Vetter of Todd-AO.
This allowed Kubrick and Alcott to shoot scenes lit with actual candles to an average lighting volume of only three candela, "recreating the huddle and glow of a pre-electrical age."
In addition, Kubrick had the entire film push-developed by one stop.
- Source Wikipedia