35 vs s35,acadamic full aperture

[rmshkarthik]

hello. could i know fewdoubts about 1.basic difference in s35vs 35,in lens,gate,aspect ratio?2.i am little bit doubt about acadamic aperture,full aperture?

[David Mullen ASC]

"Super-35" and "Full Aperture" are more or less the same, although Super-35 mainly implies using the Full Aperture WIDTH of the negative even if you don't use all of its height.

 

Full Aperture describes the maximum image area possible to expose on the format, from side to side and top to bottom. On a 4-perf 35mm camera, it's 1.33 : 1. Since it was used for Silent Era movies, it is also called Silent Aperture sometimes.

 

When sound-on-film was invented in 1928 (Movietone), the projection aperture was shaved off on one edge to hide the soundtrack behind the projector gate. This reduced the width of Full Aperture to something more like 1.20 : 1 (more or less the same aperture used for CinemaScope / Anamorphic.)

 

1.20 : 1 looked too square, so in 1932 the top & bottom were also matted out with a new projector aperture called Academy, which is 1.37 : 1, but smaller overall than Full Aperture's 1.33 : 1, and offset to one side.

 

Some cameras installed Academy Apertures in their gates, while others left the camera Full Aperture but offset the lens to the new center caused by Academy, and the groundglasses were changed for Academy.

 

Then after Cinerama and CinemaScope came out, Academy looked too square to people so a poor man's widescreen was invented involving using a projector mask to crop the top & bottom of Academy from 1.37 to anywhere from 1.66 to 1.85. This is called Matted Widescreen, or sometimes "flat" projection to disquish it from anamorphic or "scope" projection.

 

So even if a camera exposes Full Aperture, for a standard 1.85 movie, the lens is centered optically for the offset Academy / 1.85 area, and the groundglass shows you the framing for those formats.

 

Generally Academy / 1.85 / Anamorphic are referred to as Sound Apertures because they don't use the whole negative but leave a strip on the side reserved for a soundtrack.

 

When you order a camera to be set up for "Super-35", the lens is recentered for Full Aperture. So if the camera is 4-perf and you don't employ any hard mattes in the gate, you will expose a large 1.33 : 1 image, but most people use Super-35 either to compose a 16x9 (1.78) image for HD transfer, or crop even further to 2.39 for conversion later to CinemaScope / Anamorphic, as a way of avoiding anamorphic camera lenses. A few people compose Super-35 for 1.85 : 1 and then have it reduced in post to standard 1.85 that lies inside of Academy.

 

If you shoot 3-perf, which is 25% shorter than 4-perf, then Full Aperture is 1.78 : 1, the same aspect ratio as HDTV. You could compose for cropping to 2.39 and then converting it to an anamorphic image for making scope prints. Or compose it for 1.85, which is very close to 1.78.

 

Anamorphic photography has an aperture that is close to 1.20; the lenses have a 2X horizontal squeeze so when unsqueezed the final image is nearly 2.40 : 1.