Originally Posted by stanger89
Well the main problem is I (and I'm guessing everyone else based on the responses) isn't aware of anything like you're asking for. I can't even think of a horizontal masking system that only moves the top masking but I'm sure that's out there.
I understand everything you're trying to do, except why it has to be a curved screen. The only time (nearly) that a curved screen makes sense is in a CIH setup with an anamorphic lens. If you start zooming then the curvature is just a significant problem causer. If you zoom with the lens in place then the curvature will be incorrect for the effective throw introducing distortions. If you remove the lens and zoom without it, again, the curvature introduces distortions.
How do you think all the thousands of cinemas cope to screen 1.85, 1.66, 1.33 on a curved screen?
Do you think they have an A lens in place to stop distortion?
Every cinema that has a curved screen all over the world will display some form of distortion when screening other formats besides scope. Does the audience notice that and complain, no! You see much more distortion in fact even on a curved screen when an A lens is in place, the lens itself creates its own complex distortions, even a curved screen doesn't remove it 100%.
The distortions when screening all the other ratios on a curved screen when the A lens is out of the light path is so minimal. In fact its impossible to see without a test pattern, and we all know that's not the movie we watch.
Even highly racked projectors in places like Radio City produce incredible distortion, the screen can NEVER be angled to match the rake of the projectors. If the screen did match the rake the people in the stalls would never see the screen. I have projected film in many cinemas with a rake that's so steep and the screen only has a minimal tilt backwards, did the audience ever notice the distortion, no.....
The only place where they tried for years to make this work was when Cinerama was over....
They tried to screen 70MM and 35MM onto that DEEPLY curved screen, the distortion was really bad and in the end they abandoned that. I was projecting film in that very last Cinerama theatre in Auckland as we struggled to screen 70MM and 35MM onto that deep curve.
The shallow curve used for scope is so minimal any distortion can only be picked up as I say with test patterns.....
Ive been in this industry a very long time. Ive seem many different screens flat and curved. Im picky and have a real keen eye for top notch film presentation, I know what works and what doesn't.
I don't want to dispute the pros and cons of ratios and curved screens vs flat screens. I came to ask a question, I asked in in the wrong thread, Im trying to get the answer to my question, and that's why I moved that question to another thread.....
Great to see you too have an interest in scope and A lenses.