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 p.1 #8 · Magnification, real focal length and focus breathing (on the Nikon 100-400 f/4.5-5.6 Z) | |
Keith B. wrote:
Folks don't realize that even the relatively high-end lenses for stills cameras sometimes necessarily fall short of the highest possibilities in optical/mechanical design, which are exemplified by high-end cinema lenses. Cost and size are important to minimize for lenses that are intended to be owned and used by a sole operator, unlike cinema lenses where weight and size are traditionally not a worry. Sure, Nikon/Canon/Sony *could* make an 12:1 zoom at f/2.8 (T3.1) with minimized breathing and very close focus and costs only $113K USD, but ...no market for such a beast amongst stills shooters.
https://www.abelcine.com/buy/lenses-accessories/cine-lenses/angenieux-24-290mm-optimo-ultra-12x-full-package-s35-u35-ff-vv
That's a nearly 13 kg lens; the issue here is that cinema crews can start with 50 people showing up on site for a shoot to do various tasks. Some people will carry that lens and required tripod (which could easily be much heavier than the lens) and other support system around. Stills shooters usually work alone or if they have an assistant the task is usually manage lighting, perhaps there is a stylist, and there isn't that much of a use for a 12x f/2.8 zoom that is operated from a fixed position, it's just not a useful compromise to have. The BBC uses the Canon 50-1000 mm which is about half the weight of that lens, to shoot some of the wildlife documentary scenes, and they have pretty good resources, but they also use helicopters, drones, remote cameras etc. In most typical stills photography contexts, it is actually easier and more useful for the photographer to move around to capture shots from different perspectives rather than sit still and shoot from a fixed position with a heavy zoom lens, as moving position gives more options and there is no need to preserve continuity of camera position between shots, whereas in moving images a single clip can't just jump around, continuity must be managed to get a good result. So the needs of stills photographers and video- and cinematographers are very different.
On the other hand, stills shooters are typically much more interested in high image quality in terms of resolution, and because they can use fast shutter speeds, flash etc. high resolution is much more easily achieved in practice than in moving pictures. High-end cinema lenses may be optical masterpieces but their designers aim for different things as if a lens produces very detailed and contrasty images, the result may be unpleasant to watch as the different frames at 24 fps can have a kind of staccato effect while a little softer rendering by the lens may produce a more pleasing result in the context of cinema. The best image quality digital cinema cameras don't shine on resolution as much as stills cameras, and the lenses don't need to, either, since the aims are different. For example, ARRI talks about designing the lenses to be not too sharp and also to design them so that there is pleasing flare and ghosting, while a lot of the time stills photographers wouldn't be all that concerned about those things in the lenses themselves and would prefer there to be no flare or ghosting at all (there are exceptions, and a surprising amount of effort by optical designers of some of the main brands actually seems to go into consideration of bokeh, flare etc. and some of the less experienced companies and designers can emphasize MTF but then when you have some background highlights and backlighting, very unpleasant effects can show up). Anyway I would be very surprised if cinema lenses were shown to render more detail than the best stills lenses, since until very recently there was no way to actually get that into the final product (which is often mastered at FullHD/2K resolution rather than higher, and can be shot at around 4K rather than 8K or higher, not to mention the 1/48 s shutter speed).
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