Cinema lenses FOV - PLEASE HELP!!!

[Jonesy Jones]

I could really use some help. In a recent thread on this forum, I brought up, what I thought was a fact, about cinema lenses (lenses designed specifically for use on cameras with s35 sensors or film) being designed and labeled specifically for s35, and which yields roughly the same FOV as a DSLR lens on a Full Frame camera. In other words, a 50mm cinema lens on s35 would yield basically the same FOV as a 50mm DSLR lens on a Full Frame camera. That is the way it has been explained to me, though I have never owned a cinema lens nor have I had the opportunity to test this. To a large degree this is very important to me because when I read about DP's who shot such and such movies and which focal lengths they used for such and such scenes, I'd like to be clear that I understand how that info relates to my own personal equipment.

For instance, I've read Roger Deakins state that if he had to choose only one focal length to shoot a film it would be a 32mm. Obviously he is shooting on an s35 camera, so my question is, what FOV equivalent is that to the DSLR world? If we were to compare the FOV of his 32mm on s35, would it be roughly the same as a 32mm dslr lens on a Full Frame, or would it yield a FOV closer to 48mm (32 x 1.5 = 48)? 

I don't know if that's at all confusing, but this is really important to me, so let me just ask the question as simple as I can, what is the Full Frame DSLR FOV focal length equivalent to Roger Deakins' 32mm lens on s35?

 

Even that sounds confusing. lol. But please I would really love your help. Also, please briefly state your experience with both cinema and dslr lenses on both cinema and dslr lenses. In other words, I would like to make sure you are speaking from experience, not second hand information like myself. 

[Inazuma]

Super 35 is closest to APS-C, which has a 1.5x crop (or 1.6x for Canon). So to get a 50mm full frame focal length, you must use about a 35mm lens on the s35 or APS-C camera.

The reason super 35 is called that (rather than super 25 or something related to its actual dimensions) is because it uses the same film stock as 35mm SLR's but the image is only captured on a portion of it. This is as opposed to something like 16mm film where the actual film stock is smaller. And Super 16mm uses a wider portion of that film stock (to give a wider aspect ratio) which would otherwise have been reserved for the soundtrack.

[Guest Ebrahim Saadawi]

To match what Roger means on DSLRs, you need a 32mm lens on a 550D (because what he uses is s35 film, which is the same size as 550d) and you'd need a 48mm lens on a 5D (as it has a image format than s35) 

and a 50mm cinema lens on a s35 film camera gives the same FOV as a 100$ 50mm 1.8 lens on the same s35 film camera. 

 

your confusion seems to be started with an uninformed statement about cinema lenses 

[fuzzynormal]

Just know that lenses have a focal length measurement (millimeters) and it doesn't matter what camera you try to attach it to, that number is what it is.  

1. the distance between the center of a lens or curved mirror and its focus.

No reputable lens manufacturer is going to put inaccurate "equivalency" numbers on their lenses.  They're going to put down the number that represent the actual physical measurements.  The no reason to do it any other way 

It's kinda odd how any notion otherwise got stuck in your brain, but I know for someone starting all this imaging stuff and jargon, it can be discombobulating.

FWIW, I've been shooting motion images and still for decades with cameras of all "sensor" sizes.  8mm up to 4x5.  

This FOV stuff is so second nature to me now that I just kinda visualize the FOV in my head based on the glass-mm/camera-format-size and carry on.

 

[MattH]

The crop factor for super35 is 1.4463 (36/24.89)

32 times 1.4463 is 46.28 full frame equivalent. 

So to get closest you would want a 28mm lens on canon apsc (1.62) giving you 45.36mm equiv.   And a 30mm on other apsc (1.52) giving you 45.6mm equiv.

18mm on gh4 4k crop mode (2.5) giving 45mm equiv.

Or if you have another system, in order to get the accurate crop factor just divide 36 by the active sensor width in mm.

[Jonesy Jones]

Ok. Well, sounds like I understood this all wrong. Thanks guys. 

[Guest Ebrahim Saadawi]

What's a 32mm lens anyway? I mean why would one choose this as a favourite and not 35mm? Is there really a difference? I don't think there is. In fact, Canon's 35mm is similar in field of view to Sigma's 30mm, so there's a slight room for error that makes the difference between 32mm and 30 or 35mm not visually visible. Is it just for the sake of difference as there arent many 32mm lenses out there or did he give a specific reason? or is he talking about a specific lens he happens to own and use and love that's 32mm. 

 

it's an interesting point definitely on why Dekins chooses a 32mm lens as his favourite. 

 

[IronFilm]

Yup, he is talking about a literal 32mm lens.

In photography there is often quite a big leap in primes from one to the next, but not so much with high end cinema lens. Which can have much smaller steps between them.

Here is a couple of examples of 32mm lenses:

http://www.bhphotovideo.com/c/product/664902-REG/Cooke_CKEP_32_Panchro_32mm_Prime_Lens.html

http://www.abelcine.com/store/Arri-Zeiss-32mm-Ultra-Prime-Distagon-T1.9/

But yeah, if you're looking for an affordable one that you could buy yourself. I'd say just go for the Rokinon Cine DS 35mm T/1.5 in the Nikon F mount (I've got one myself).

[Jonesy Jones]

Yes IronFilm, Deakins is referring to that Arri Zeiss 32mm, but I think it's not so much the brand, but the focal length. I assume his reasoning is that 32mm gives him a FOV he likes, and it's a pretty normal lens, now that I know it is still subject to the 1.4 crop factor. 

[Nick Hughes]

Keep in mind that Deakins (or any other Hollywood director) very likely does not think about s35 in terms of it's crop factor vs full frame. Full frame is not a cinema standard- this is where I think a lot of people get tripped up. To him, s35 is a 1x crop and if he happens to use a 5D on a shoot, he probably thinks of that as a .7x crop! 

[IronFilm]

Roger Deakins doesn't go around thinking about full frame crop factor! LOL

"full frame" and "crop factor" are two of the most genius bullshit marketing terms which have been inflicted upon the poor consumers by Canikon, so as to get them to spend more on their products so as to feel "full" and not "inadequate".

[Chrad]

Bear in mind that Deakins is using an Arri Alexa these days, with a sensor slightly smaller than the super 35 negative in the diagram. So if he uses this lens with the Alexa, he's shooting with a field of view comparable to a true 48mm on a full frame DSLR. I'd say a 50mm will do.

Of course it's not all about f.o.v., but also the depth of field characteristics of that focal length and the characteristics of the particular lens that matter as well.

[M Carter]

The incorrect info was that S35 = full frame DSLR or 35mm stills camera. Just need to get into your head that s35 is closer to APS-C (really DX) - similar width, S35 is a bit taller aspect-ratio wise - not exact but ballpark.