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Forums > Back > Canon EOS R system announced
Brightcolours
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#41
10-30-2018, 03:18 PM
Quite positive/glowing review from Canon-fanboi Jared Polin.
https://www.youtube.com/watch?v=C791UkqhBU8
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martind86
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#42
11-02-2018, 12:01 PM (This post was last modified: 11-02-2018, 12:17 PM by martind86.)
Not very practical but remarkable optical achievement for sure (if it becomes reality):

 https://www.canonnews.com/canon-patent-application-canon-rf-14-21-14
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Brightcolours
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#43
11-02-2018, 12:16 PM
Actually, the patent describes a 14.5-21mm f1.55 lens.
And a 16-35mm f2.8 lens, and a 12-20mm f2 lens.
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Rover
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#44
11-03-2018, 04:24 PM (This post was last modified: 11-03-2018, 04:27 PM by Rover.)
You know they'd round the aperture figure down, and the focal length numbers in whichever direction helps selling it better. Big Grin Everyone does because - say - 24-70/2.8 sounds way sexier (and more marketable) than 25.5-65/2.95. Smile
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Brightcolours
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#45
11-04-2018, 09:40 AM
(11-03-2018, 04:24 PM)Rover Wrote: You know they'd round the aperture figure down, and the focal length numbers in whichever direction helps selling it better. Big Grin Everyone does because - say - 24-70/2.8 sounds way sexier (and more marketable) than 25.5-65/2.95. Smile

I know that Canon lenses are usually designed to be close to what they say they are. So, a f1.4 lens actually is a f1.4 lens. Making a fake example of the 24-70mm f2.8 does not change that much...
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Rover
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#46
11-04-2018, 10:38 AM (This post was last modified: 11-04-2018, 10:40 AM by Rover.)
Check the DPReview.com data - they are actually measuring the focal length of lenses they evaluate. You may be in for a surprise - especially at the long end of zoom lenses, actual focal lengths are especially often shorter than stated. Smile
That's not to say that slightly rounding focal lengths is not an industry wide practice. Who can blame them for that (I certainly do not).
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Brightcolours
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#47
11-04-2018, 02:20 PM
(11-04-2018, 10:38 AM)Rover Wrote: Check the DPReview.com data - they are actually measuring the focal length of lenses they evaluate. You may be in for a surprise - especially at the long end of zoom lenses, actual focal lengths are especially often shorter than stated. Smile
That's not to say that slightly rounding focal lengths is not an industry wide practice. Who can blame them for that (I certainly do not).

1st of all, I somehow doubt that DPReview can measure focal lengths well ;Wink
How are they going about to determine front and back nodal points? They probably use a simple formula which can't really be applied and will always give (too) short focal lengths.
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