Full Aperture vs Super 35

[David Cunningham]

Hi All,

 

I apologize if this has been asked/answered before, but I cannot find anything clearly dealing with this already in the forums.

 

I understand the difference between Super35 and Full Aperture is simply the lens centering position. Full Aperture and Super 35 have the same full width gate but Full Aperture is lens mounts are centered slightly offset as if the gate were actually an Academy gate so that framing will be at the lens center when cropping for Academy. This is especially important in anamorphic shoots so you know exactly where the center of the squeeze is. True Super 35 has the lens centered on the center of the frame expecting a scan and crop, likely to 16x9 for HD TV.

 

Based on my calculations, the difference in lens centering position would be less than 1.5MM off center to the non-sound track side of the frame. This seems like it will be pretty much meaningless unless you are shooting anamorphic or heavily zooming during a scene. When used with primes this offset is probably negligible and makes for no real visual difference, am I wrong?

 

And, if I want to shoot anamorphic, the lens being centered for Academy means I need only frame my scan for Academy and now my anamorphic centering is correct. Right?

 

In short, I'm asking because I have an Academy centered full aperture camera that I want to use for all purposes (Super 35 cropped for HD, Academy 35mm for anamorphic, etc). There is no real drawback (or reason to recenter the lens) unless I want to zoom mid shot when shooting full width Super 35/Full Aperture.... correct?

 

Most of the time I would shoot with a prime or a zoom without zooming and scan the full width of the frame, then crop top and bottom for a wide-screen aspect ratio. Other than zooming mid shot, there is no real reason to recenter my lens for this, correct?

 

Thanks!

 

Dave

[David Mullen ASC]

Full Aperture is the same as Super-35 but you can run into cameras that have the lens centered for Academy Aperture but expose Full Aperture.

[David Cunningham]

Full Aperture is the same as Super-35 but you can run into cameras that have the lens centered for Academy Aperture but expose Full Aperture.

 

 

Hi David,

 

Yes, that's exactly my situation. What do you think about my questions related to this scenario?

 

Dave

[Dom Jaeger]

You can get issues with image circle coverage if a lens only just covers S35 but is not centred to the full aperture. You might find one side has darker corners and more aberrations than the other side, or actual portholing.

 

Also if there is any lens distortion it will be offset, which might be distracting.

[David Mullen ASC]

"Silverado", which was an early Super-35 (aka Super Techniscope) feature, used some Arri-2C's for some MOS shots that exposed Full Aperture but were centered for Academy. As long as the lens didn't vignette, it was OK but as Dom mentioned, you can have some issues if the lens has obvious barrel distortion on the sides, or other artifacts. Flares will be slightly off-center when the light seems to be in the center of the lens, but I've shot a number of 3-perf Super-35 films with 1/4 offset 2.40 extraction, so the center of 2.40 is shifted a bit higher than Full Aperture, which in theory would affect zooming and flares, but it wasn't really an issue.

[David Cunningham]

Thanks everyone! Good to know!

[Will Montgomery]

Similar issues come up in Super 16 conversions that are done only half way; just enlarging the gate to one side. Without re-centering the lens mount you can some strange lens issues, especially when using a zoom lens (when zooming) which is probably more common with Super 16.