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Comment by SpliffnCola | Hacker News Reader

If you are wondering who the target audience this cine camera is for then you are not the target audience.

To those asking why it doesn't have AF: no cine camera has AF.

In regards to lens selection; the camera seems to be modular so there shouldn't be much stopping Axiom or yourself from getting a different lens mounting plate.

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While it's accurate that cine cameras use a human focus puller, its an oversight in this cameras engineering not to include a way to drive the len's focus or the aperture. (Blackmagic's early cinema cameras used these 'dumb' mounts, too, but it frustrated users because they couldn't electrically run the len's controls.)

Having an API for the lens and aperture would have opened it up for developers to use these creatively, such as focusing on one point in the frame and then zipping focus to another point using easing functions.

Agreed on all points. Due to the modular design, and I'm assuming here, it seems wireless (and on camera) focus pulling could be added onto the cam.

Something like http://www.rtmotion.com/lens-control-system or https://cinegears.com/product/cinegears-single-axis-wireless...

Not sure about aperture adjustment from the cam body itself; usually, not always though, cine lenses are constant aperture primes or zooms.

Cine lenses almost universally have variable aperture. When a zoom is "constant aperture" what is means is that the maximum aperture is the same across the entire focal range, not that you cannot close it down when needed.

Thanks for the correction. That aspect slipped my mind.

Blackmagic make video cameras for a specific niche and they're great (I want one myself). But most of their customers buy into the Micro 4/3 mount system. PL mount type cine lenses have never had autofocus and likely never will. The job of the focus puller is not just to keep things in focus but to adjust in harmony with the mood and pace of the scene. There are separate remote lens control systems for when a camera is mounted on a gantry and so on. Framing and focus are treated as distinct jobs on a large set.

Cine lenses don't have camera-operated controls, so it wouldn't work. You could control the aperture of some 'interesting for cinema' lenses (Zeiss Otus for Canon mount, for example) from the camera, but this would require unwarranted amount of reverse engineering.

Active lens mounts are on the road-map: https://www.apertus.org/axiom-beta-status but it will indeed require a serious amount of reverse engineering for each different lens system: https://wiki.apertus.org/index.php/Lens_mounts

> no cine camera has AF

How about the https://en.wikipedia.org/wiki/Canon_EOS_C300_Mark_II with dual pixel autofocus?

Sure and that's incredibly useful for event and documentary film making.

When it comes to cinema _movies_ (while it's true the EOS C300 Mark II has dual pixel AF) there will be a focus puller.

Relying on AF will end up biting your ass on a film set. Auto-focus doesn't know about the aesthetic of the film, only that something (a face) is in focus.

On (movie) sets the cinematographer will be making those decisions, not AF; while it does, "...[enable] the user to see if they are focused in front of or behind the subject through visual observation, [allowing] quick and accurate manual focus to be achieved" it should only be used in movie making as a tool and not a crutch.

You're technically correct on the existence of AF in the C300 MII.

Edit: Cine cameras are beginning to delve into AF but it is not replacing a focus puller anytime soon.

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