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06-08-2016, 03:41 AM - 4 Likes   #31
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The aperture is controlled and commanded by an electromagnet and not a mechanical device. It's cheaper, more precise and allows for continuous and smooth variation in the aperture, which is a highly desirable feature in video mode.

All Canon lenses have such a device since the first day of the EOS system and so do all recent Nikon lenses (the "E" series).

Having the K mount allowing for electromagnetic control of the aperture is also important because it abolishes a barrier for third-party lens makers (think: Sigma) to produce K-mount versions of their lenses.

06-08-2016, 03:47 AM   #32
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so this combinations is squarely aimed at 'soccer moms'
06-08-2016, 03:48 AM   #33
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QuoteOriginally posted by Imp Quote
no more mechanical linkage? or does that mean something else?
We'll know when we get a look at the rear mount face and see what is or isn't there.

I notice that it appears to be about half a stop slower at both ends, too. The original was 4.0 to 5.8
06-08-2016, 04:02 AM   #34
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QuoteOriginally posted by Mistral75 Quote
The aperture is controlled and commanded by an electromagnet and not a mechanical device. It's cheaper, more precise and allows for continuous and smooth variation in the aperture, which is a highly desirable feature in video mode.

All Canon lenses have such a device since the first day of the EOS system and so do all recent Nikon lenses (the "E" series).

Having the K mount allowing for electromagnetic control of the aperture is also important because it abolishes a barrier for third-party lens makers (think: Sigma) to produce K-mount versions of their lenses.
Exactly ! I think it will also allow for cost reduction as the same aperture mechanism will probably be used in all next lenses.

---------- Post added 8th Jun 2016 at 01:05 PM ----------

QuoteOriginally posted by Imp Quote
Aha, so it IS built for video... the plot gets thicker
indeed

06-08-2016, 04:14 AM   #35
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QuoteOriginally posted by aurele Quote
Exactly ! I think it will also allow for cost reduction as the same aperture mechanism will probably be used in all next lenses.

(...)
Not yet, unfortunately, not until all then current bodies support this feature. And the future lenses with an electromagnetically-controlled aperture and no aperture-coupling lever will only be usable with K-70 and the following bodies.

Last edited by Mistral75; 06-08-2016 at 04:21 AM.
06-08-2016, 04:20 AM   #36
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Pentax 18-270mm

QuoteOriginally posted by Ole Quote
What about the DA 18-270? It is fairly compact so no need for the retractable feature and it exists today.
Thanks for the heads up, Ole! I'll check into that lens,....

Jack
06-08-2016, 04:22 AM   #37
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Diameter increased from 71 to 76,5 mm
Length decreased from 111,5 to 89 mm
Weight decreased from 450 to 440 gram
# lenses increased from 12 to 14
# groups increased from 8 to 11
# diaphragms increased from 6 to 9
Focus group moved back
Close focus distance decreased from 140 to 95 cm
Focusing should be much faster
06-08-2016, 04:24 AM - 3 Likes   #38
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QuoteOriginally posted by D1N0 Quote
so this combinations is squarely aimed at 'soccer moms'
Also known as "people who buy cameras."

06-08-2016, 04:28 AM   #39
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QuoteOriginally posted by Simen1 Quote
(...)
Focusing should be much faster
So they say themselves:
QuoteQuote:
- Compared to the current 55-300mm, focus is 8.3 times faster on the wider angle side and up to 1.7 times faster on the telephoto side
06-08-2016, 04:29 AM   #40
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QuoteOriginally posted by Mistral75 Quote
Not yet, unfortunately, not until all then current bodies support this feature. And the future lenses with an electromagnetically-controlled aperture and no aperture-coupling lever will only be usable with K-70 and the following bodies.
This could be updated via firmware I would think. otherwise this new lens won't work on any body, unless it also has mechanical coupling.
06-08-2016, 04:31 AM   #41
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QuoteOriginally posted by D1N0 Quote
This could be updated via firmware I would think. otherwise this new lens won't work on any body, unless it also has mechanical coupling.
I presume it does since they write:
QuoteQuote:
- High-precision exposure control in movie mode when paired with K-70
06-08-2016, 04:38 AM   #42
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QuoteOriginally posted by Mistral75 Quote
I presume it does since they write:
But it must be firmware since it doesn't have a different mount spec. It's KAF 3
06-08-2016, 05:00 AM   #43
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QuoteOriginally posted by D1N0 Quote
But it must be firmware since it doesn't have a different mount spec. It's KAF 3
Where did you read a reference to K-AF3 in conjunction with K-70 or 55-300 PLM RE?
06-08-2016, 05:24 AM   #44
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I didn't see KAF 4
06-08-2016, 05:32 AM   #45
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QuoteOriginally posted by D1N0 Quote
I didn't see KAF 4
Are you a lawyer, a politician or both?
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