>From my experience directors and DOPs always assumes a lens is on a moving picture film camera in the Super 35 format, not a 35mm stills camera. I know it's very confusing that they almost have the same name, but the film back size is very different. On a 35mm stills camera (Nikon D4/D800 and Canon 1D, 5D), the Film Aperture width is 36mm (yes 36 and not 35). The Super 35 film format used for movies has a Film Aperture width of 24.89mm. This format is very rare now in the digital age but the Red and Alexa follows the Super 35 standard pretty closely with the Alexa at 23.76mm and the Red Epic at 27.7mm. The Nikon DX format and Canon APS-C cameras also has a size very close to Super 35. In fact, the majority of DOPs I've met actually use Nikon DX cameras, probably because they can just shoot stills on location scouts and tech recces and know they can use the same focal length when shooting with the Red or Alexa.
Bottom line... if a director or a DOP talks about a 40mm lens, it's probably safe to assume a Film Back (Film Aperture) of around 24mm (Super 35), but if you're in doubt, just ask him/her. Personally, I always set Softimage to use the Alexa size of 23.76mm because 90% of all the work we do with live action is shot on the Alexa. Of course I change the Film Aperture if it's shot on anything else. It's also worth noting that depending on the resolution/format being recorded on Alexa and Epic, they use different amount of pixels on the sensor and thereby changing the size of the Film Back as well. Hopes this clears it up further. /Jens On Fri, Apr 19, 2013 at 1:45 AM, Raffaele Fragapane < [email protected]> wrote: > The director might need to read into the fundamentals of his job. > In first place the focal length doesn't mean much without knowing how big > the film back is and where it is. > > 40mm on a m4/3 (or any small sensor) is a fairly long lens, like shallow > depth portrait long. On an Epic it's actually closer to a 37mm on a 35's > film back, and on a 35's film back it's a natural lens. > > Assuming that, like many, he assumes the 35mm film standard (not to be > confused with a 35mm focal length), you should set your film back to a 35mm > full frame sensor settings, and then whatever focal length will match his > expectations. > If he refers to lenses he shot plates with, he needs to let you know what > they were shot with. > > Shooting with a GH3, a m4/3 black magic, a 5D MIII, a Phantom or an Epic > all respond from wildly to slightly differently to focal lengths. > > The settings in Soft make perfect sense, and the ones in Maya don't differ > really, just some of the camera settings are actually stashed away or > slightly odd. > It's time to study the basics of photography/camera work if you think the > ones in Soft don't make sense. The only difference is Maya might have > defaults and things hidden away that for the one sequence happened to be > lucky, but the two apps don't differ. > > > On Thu, Apr 18, 2013 at 8:26 PM, Ben Beckett <[email protected]> wrote: > >> Sorry maybe I have confussed I mean the standard numbers such as 40mm >> 35mm 22mm lenz, When he said lets try a 40mm lenz how does that equate in >> soft >> >> Thanks >> >> >> On 18 April 2013 11:10, Jens Lindgren <[email protected]>wrote: >> >>> Yeah the Film Aperture should really be in mm in Softimage... Don't get >>> why it's in inches. >>> >>> /Jens >>> >>> >>> On Thu, Apr 18, 2013 at 12:08 PM, Leonard Koch <[email protected] >>> > wrote: >>> >>>> I would think because mm is the standard in focal lengths. >>>> Lenses' focallengths and also sensor sizes - which also play a role in >>>> how much the camera sees - are always given in mm. >>>> On Apr 18, 2013 11:44 AM, "Ben Beckett" <[email protected]> wrote: >>>> >>>>> Hi >>>>> >>>>> Maya's cameras clearly have a defined Focal Length Tab. >>>>> >>>>> Where in Soft is this because sitting with the Driector yesterday soft >>>>> really did it self no favours, I was telling him how it a great app is but >>>>> he now not having any of it. >>>>> >>>>> On the camera prop's menu there is the Focal Length but its in (mm) >>>>> , can it be switch, and why mm's. >>>>> >>>>> Thanks >>>>> Ben >>>>> >>>>> >>>>> >>>>> >>> >>> >>> -- >>> Jens Lindgren >>> -------------------------- >>> Lead Technical Director >>> Magoo 3D Studios <http://www.magoo3dstudios.com/> >>> >> >> > > > -- > Our users will know fear and cower before our software! Ship it! Ship it > and let them flee like the dogs they are! > -- Jens Lindgren -------------------------- Lead Technical Director Magoo 3D Studios <http://www.magoo3dstudios.com/>
