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Old 08-12-2018, 02:09 PM
Kedikat Kedikat is offline
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Different take on camera design

Never mind. Found it already exists.

Last edited by Kedikat; 08-12-2018 at 02:12 PM. Reason: New information.
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Old 08-12-2018, 02:17 PM
rat avatar rat avatar is online now
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You wouldn't change the "zoom" ratio but the focus distance of the lens elements.

This is why you use extension tubes to increase the magnification of macro lenses because it allows you to focus closer. It also causes problems with correction of color and other aberrations and would complicate the micro-lens construction on the sensor.

It is also far harder to maintain a perfectly flat orientation with that type of movement as so it ends up being easier to just move the entire lens.

There are several lens designs that use to be based off moving all of the lens groups for zoom in the past and some are still used but only in low cost low performance designs like webcams.
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Old 08-12-2018, 02:28 PM
scr4 scr4 is offline
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Sure it's possible - and it's been possible, it's just a matter of putting a focusing mechanism between the film and the lens mount. View cameras and press cameras are like that.

It wasn't done for SLRs because the amount of focus adjustment is different depending on the type of lens, and because many lenses move internal elements as well as moving the whole lens assembly back and forth. So there needs to be a linkage to move the camera's focus mechanism in sync with the mechanism in the lens.

With electronic controls it's a bit easier to do, but I really don't see any advantage. You're just moving one mechanism from one part to another. And you still have the issue of the movement not being optimized for each lens.

Last edited by scr4; 08-12-2018 at 02:29 PM.
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Old 08-12-2018, 04:17 PM
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Since the question has been edited out of the OP, I am going to close this.
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