Erkan Umut

We learned that F/50mm is the normal lens for 35mm format and F/25mm for 16mm format. So, in theory, F/25mm will be a wide angle lens for 35mm format and F/50mm will be tele lens for 16mm format. Recently, for my project shot in Super16, the rental house recommend me to use F/12mm lens made for 35mm format instead of F/6mm lens made for SUPER16 format. Because of above theory, I accepted it. But I surprised when I saw that F/12mm didn't give me the result of F/6mm of Super16 lens... What is the reason? Thank you for your explanations... :)

The new forum site is created on all kinds of motion-picture technology, and waits for your registration: Cinema Technology Forums Thank you...

Skipping (you say strobing) also related to the shutter position. If you expose the film by reflex mirror shutters at 45 degree position (not the opening angle!) btw the lens and aperture like in ARRIs, you gonna get more skipping while fast panning than the focal plane shutters like in Panaflexes or eclair ACL. Because the focal plane shutter is completely close to the aperture, so it means that it cuts the light at very narrow cone point (here we call the exposing light rays as a cone). Also, contrarily panning to direction of shutter rotation causes more skipping.

Dear Thibaut, I need the service manuals e.g. parts catalogues of eclair NPR & ACL. If you have scans still, could you please email me. Thanks a lot... :)

Thanks... I eagerly am waiting for your observation... By the way, my hobby is motion-picture technology. What is your field? I've been in Japan in 1995 for one month, and have visited the projector makers Tokiwa Tokyo, Eiki Osaka and Elmo Nagoya, and was the Agent for Tokiwa in Turkey. Japan is one of the makers of high quality precision cine machinery... Do you have have any manual and parts catalogue of the latest model eclair ACL? Pls. visit my web at http://www.erkanumut.com/acl.htm

Thank you for your reply and the diagram. What is the source of your diagram? Any publication or your experience? The light through the lens results a cone towards the aperture. The focal plane shutter is very close to the aperture, so it cuts the smallest part of this cone. I've seen similar things in Russian cine technology books I have. Any comments...

This is a quote from eclair ACL manual: Contrary to reflex cameras in which the mirror mounted at 45' acts as a shutter, the ACL has a plane shutter of large diameter completely independant of the mirror (14). It is placed very close to the film plane with an opening of 175'. Cutting the image in the direction of the smallest dimension gives a perfect exposure, maximum definition and reduction of jerky effect on some panning shots. What does it mean "cutting the image in the direction of the smallest dimension"? Does it mean the shutter is placed very close to the aperture, or? Why do mirror shutters (placed at 45') cause the jerky effects while quick panning? Similar system applies to Panaflex cameras as far as I know. Does someone have the system diagram and info about the shutter and mirror of Panaflex cameras? Thank you for all... :)

Are there any previsualization software for lighting design (where you assign the lighting equipment, their densities, color and effect gels, exposure parameters, and their results on the subjects and cast in a 3D environment) specially made for cinematographers? I mean the FreameForge-like tool for DoPs and Gaffers... :rolleyes:

As far as I know, Konvas uses retarded pull-down cycle same as Arri IIIC (maybe in IIC, I'm not sure). The claw waits engaged with the perforation until its movement for the next frame advance. I call it artifical register-pin :). And I remember that once OSTCAM of Moscow had made a register-pin for Konvas 2M... The clips of Thomas are very informative, but I prefer to look at the tests especially for registration shot on tripod totally locked, and best of best shot the Vernier pattern.

I know that KONVAS cameras have single-blade 150deg mirror shutter. Recently, I have seen a two-bladed butterfly mirror shutter for KONVAS on internet. Is it possible to use it by changing the shutter gear? The butterfly types must rotate slower than the single blades. So it could be an advantage... Any comments?

How does KONVAS stop the shutter in closed position when its off? By electronically via sensor feedback (like in CP-16R cameras) or mechanically (like in Bolex cameras)?

"1KCP-1M.07.000" orientable viewfinder is used for both of 1M and 2M cameras. Is there also any special viewfinder for 2M camera or? What are the exact working angles of these viewfinders?

Finally, I add the pix requested... Ostcam 16, Ostcam 35 and StarCam 35 respectively:

Dear Kevin, I could not embed the pictures, I don't know why, and the Cinematography forum site is very limited to me... If you and anyone want to get the pictures, I can send them via email. Please send your email address via personal message. Best, Erkan

Ostcams are history now... Here are few pix.

What is Phase Shifting when filming video and computer monitors? How does it assure in cameras with shutter and pulldown mechanism are mechanically coupled? If its by means of specific speed, it will affect the exposure time and the motion in the video picture...? How does it assure in cameras with shutter and pulldown mechanism are electronically coupled or independent (like in ARRI 435)? If its by means of shutter timing, it will affect the exposure time...?