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08-29-2018, 07:11 PM   #1
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Zoom zoom zooms

There are several varieties of zoom lenses:

  • One-touch (zoom and focus with same ring)
  • Two-touch (two different rings, one focuses, one zooms)
  • Push-pull (rotate to focus, pull to zoom, may be autofocus)
And then there's the weirdest of all: the zoom lens that is most telephoto when the zoom is closest to you, and widest when the zoom is farthest away from you. (this is generally a push-pull and/or one-touch zoom).

Why do you suppose the weirdest ones exist?

And have you seen any other varieties of zoom lenses?

08-29-2018, 07:36 PM   #2
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The power zoom which zooms at the touch of a switch.
08-29-2018, 07:47 PM   #3
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QuoteOriginally posted by Mikesul Quote
The power zoom which zooms at the touch of a switch.
It doesn't seem so weird if you consider than most point-and-shoot film cameras of the same era had push-button zooming. But it doesn't really add as much to an interchangable lens.
08-29-2018, 07:51 PM   #4
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Pentax made several. In fact, i believe the sdm contacts were based the the earlier power zoom contacts.

08-29-2018, 08:52 PM   #5
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QuoteOriginally posted by Mikesul Quote
Pentax made several. In fact, i believe the sdm contacts were based the the earlier power zoom contacts.
They are one and the same.
08-29-2018, 09:49 PM   #6
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Isn't one touch the same as push pull?
08-29-2018, 10:23 PM - 1 Like   #7
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QuoteOriginally posted by timw4mail Quote
And then there's the weirdest of all: the zoom lens that is most telephoto when the zoom is closest to you, and widest when the zoom is farthest away from you. (this is generally a push-pull and/or one-touch zoom).

Why do you suppose the weirdest ones exist?
If the lens is shortest at the tele position, you can handle it in a more stabilized way. At widest (longest), your hand-shaking is less of an issue... deflection angle and so on...

Last edited by yucafrita; 08-29-2018 at 10:32 PM.
08-29-2018, 10:27 PM   #8
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QuoteOriginally posted by UncleVanya Quote
Isn't one touch the same as push pull?
No, push-pull can be two-touch.

08-30-2018, 05:47 AM   #9
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QuoteOriginally posted by UncleVanya Quote
Isn't one touch the same as push pull?
I always thought so
QuoteOriginally posted by timw4mail Quote
No, push-pull can be two-touch.
I guess there are some that aren't though
08-30-2018, 06:22 AM   #10
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QuoteOriginally posted by UncleVanya Quote
Isn't one touch the same as push pull?
QuoteOriginally posted by MossyRocks Quote
I always thought so

I guess there are some that aren't though
As an example:

I have a Nikon AF 70-210mm 1:4-5.6 D lens, which is an autofocus lens, so it is not a one touch zoom. The focal length is changed similar to a one touch, but it doesn't rotate (as the zoom grip doesn't affect focus).




Also I have a few examples of 3 touch zooms, with focus, zoom, and macro/close up rings.
08-30-2018, 06:28 AM - 1 Like   #11
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QuoteOriginally posted by timw4mail Quote
As an example:

I have a Nikon AF 70-210mm 1:4-5.6 D lens, which is an autofocus lens, so it is not a one touch zoom. The focal length is changed similar to a one touch, but it doesn't rotate (as the zoom grip doesn't affect focus).




Also I have a few examples of 3 touch zooms, with focus, zoom, and macro/close up rings.
Thanks. Now I know more than I did when I got up.
08-30-2018, 06:56 AM   #12
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QuoteOriginally posted by MossyRocks Quote
Thanks. Now I know more than I did when I got up.
Learning can be fun, as can sharing knowledge
08-30-2018, 07:47 AM - 1 Like   #13
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The DA 16-45/4 extends the most at 16mm. That ends up blocking the popup flash, but doesn't seem to affect my usage otherwise.
08-30-2018, 08:01 AM   #14
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QuoteOriginally posted by timw4mail Quote
Learning can be fun, as can sharing knowledge
Isn't that why we are here, and to look at pretty pictures or maybe win a camera?
08-30-2018, 11:33 AM   #15
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QuoteOriginally posted by Just1MoreDave Quote
The DA 16-45/4 extends the most at 16mm. That ends up blocking the popup flash, but doesn't seem to affect my usage otherwise.
Huh, I didn't know that there were any autofocus zooms that are "backwards" (for lack of a better term).
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