I've had an idea for quite a while for something that I believe would allow better control of focus with modern electronically controlled lenses (focus-by-wire) on video-oriented DSLR and mirrorless cameras, and always wondered why no one has implemented it yet.
The idea starts with the premise that speed and acceleration of the lens focus ring turns is controlled in firmware somewhere. In other words, the frustrating effect that we encounter that makes it so when we turn the focus ring slowly it takes more than a complete rotation to go from near focus to far focus and vice-versa, while a fast turn of the focus ring takes less than a complete rotation must be set in either the lens or the camera firmware. This ends up killing any chance for a predictable focus pull or focus rack on these electronic lenses, and just generally makes focusing on these electronic lenses a pain for video.
Why not expose controls for those firmware settings in the UI of the camera somewhere? In particular, I envisioned a settings UI that would do the following:
1. Allow you to turn the acceleration for the lens rotation sensor on or off. This should theoretically make it possible to set repeatable focus marks on these electronically-controlled lenses by just turning the acceleration off.
2. Allow you set a range of multipliers, like 0.5x, 1x, 2x, etc for the lens rotation sensor. This should theoretically allow you to control how much you needed to turn the ring to traverse the focus range of the lens - a tiny turn if you need the speed, or a huge turn if you need the precision, and several different focusing speeds in between.
This seems to me like it would be a fairly simple thing to implement in software and that it would make for a pretty nice selling point for a camera, but either I'm underestimating the difficulty of doing this or no one has either thought of this or bothered implementing it.
Does anyone have any insights into camera or lens firmware that could clarify if such controls/settings would be possible, or feasible?
The idea starts with the premise that speed and acceleration of the lens focus ring turns is controlled in firmware somewhere. In other words, the frustrating effect that we encounter that makes it so when we turn the focus ring slowly it takes more than a complete rotation to go from near focus to far focus and vice-versa, while a fast turn of the focus ring takes less than a complete rotation must be set in either the lens or the camera firmware. This ends up killing any chance for a predictable focus pull or focus rack on these electronic lenses, and just generally makes focusing on these electronic lenses a pain for video.
Why not expose controls for those firmware settings in the UI of the camera somewhere? In particular, I envisioned a settings UI that would do the following:
1. Allow you to turn the acceleration for the lens rotation sensor on or off. This should theoretically make it possible to set repeatable focus marks on these electronically-controlled lenses by just turning the acceleration off.
2. Allow you set a range of multipliers, like 0.5x, 1x, 2x, etc for the lens rotation sensor. This should theoretically allow you to control how much you needed to turn the ring to traverse the focus range of the lens - a tiny turn if you need the speed, or a huge turn if you need the precision, and several different focusing speeds in between.
This seems to me like it would be a fairly simple thing to implement in software and that it would make for a pretty nice selling point for a camera, but either I'm underestimating the difficulty of doing this or no one has either thought of this or bothered implementing it.
Does anyone have any insights into camera or lens firmware that could clarify if such controls/settings would be possible, or feasible?
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Any additional information that you can point me to? A google search using those terms didn't yield anything.