Bolex & Sekonic Meter

[@erwinb3412]

Why do you read from 1/80th of a second and not from 24frames/second on the bottom of the seikonic lightmeter ? If you film with 24fr/s , and you read from 24fr/s on the seikonic , isn't then the reading different than from 1/80th ? Also , you use a reflex Bolex H16 (rex5 i think) . So shouldn't you use 1/65th of a second , instead of 1/80th ? Regards , Erwin .

[@isaacbrooks5412]

The 24fps hash mark on the light meter (also marked “Cine”) is based on a 180 degree shutter, which the Bolex does not have. The Bolex does have a 1/65th of a second shutter time, based on its 133 degree shutter, but you need to account for the fact that the Bolex’s prism takes about 25% of the light from the camera’s lens before it passes through the shutter opening, and hence you arrive at 1/80th of a second for the effective shutter speed, while filming at 24fps.

[@tekoppentekoppen761]

On my supreme it says that the shutter angle is 144.

[@isaacbrooks5412]

Hey, the non-reflex versions are likely different - it has been awhile. These versions used in the video are all reflex /H16s and have the 133 degree shutter. Not a big difference in speed overall. How’s that camera working for you?

[@tekoppentekoppen761]

@@isaacbrooks5412 I just bought film for it. Big investment already. I have a regular sekonic 308 for still. But was thinking if I need a better one...

[@isaacbrooks5412]

@@tekoppentekoppen761 Solid meter. 758 Cine for my own work. We use the classic Sekonics where I am employed. Let us know how the footage looks.