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Forum: Pentax News and Rumors
06-17-2020, 06:20 PM
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Yes, Tamron do have a factory in Hanoi ... the conspiracy lives on! :D
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Forum: Pentax News and Rumors
06-17-2020, 05:25 PM
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?
I have the DFA 50 Macro, it purple fringes in water, bright metals, etc - and that's at f2.8! :)
It will have way more chromatic aberration than the DFA*50, which has very little, possibly better than any autofocus fifty of any brand.
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Forum: Pentax News and Rumors
01-13-2019, 04:02 PM
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No, I've never seen a lens or read a performance chart for one where best performance didn't occur one to two stops down.
The light from the edges is inferior to the light coming straight on. The more you open a lens the more of this poorer light you have to correct or deal with.
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Forum: Pentax News and Rumors
01-13-2019, 02:52 PM
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Yeah, you can google 'retrofocal lenses' or similar to see the mirrorless problem.
A larger mount diameter *does* help, this is a Sony and Fuji problem because their mirrorless mounts were both designed for APS-C.
By starting from scratch, Nikon are showing off with that f0.95 lens because to try that on Sony's E mount would result in embarrassing wide open performance. Mitakon are brave enough to make one, but I don't know how bad it is.
Canon had the same problem with their mirrorless EF-M mount.
It's a disaster like that, no matter how many units they sold they'll probably have to orphan it and put their efforts into the RF Mount that's wide enough for high performance lenses.
Btw, K Mount is fine, it was originally for 35mm film, of course.
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Forum: Pentax News and Rumors
01-13-2019, 12:23 PM
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My Sony A7 has a so-called 'thick stack' of microlenses on the sensor, my Pentax K-1 does not, it's a DSLR with a longer registration distance because a mirror is accommodated.
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Forum: Pentax News and Rumors
01-09-2019, 02:07 PM
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Actually, the focus plane for any lens is never flat.
The phenomenon's called Field Curvature, and the MTF graphs for a lens map the field out.
Managing it is one more compromise that faces the designer.
A macro lens really benefits from a flat field, so the designer will sacrifice aperture ... f2.8 is fast for a macro.
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Forum: Pentax News and Rumors
01-08-2019, 11:30 AM
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Not really a problem for a DSLR, UlrichSchuegg.
The registration distance is nice and long so that the light is coming in quite parallel, it's mirrorless that have this problem because the sensor is now so close to the rear element.
Much worse in an ultra-wide, BTW.
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Forum: Pentax News and Rumors
06-28-2018, 03:40 AM
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Not really, Torashi.
The modern DFA zooms are larger than previous FA designs.
And none of these Star primes will have 49mm filter sizes like the M series, their performance will be far superior.
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Forum: Pentax News and Rumors
06-27-2018, 07:34 PM
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The Helios has got nice personality (own one myself), but if you can get a DA*55 secondhand, you might score a great price because, amongst other reasons:
1) The 'SDM' focus system has a bad reputation
2) It's labelled 'DA' so somebody thinks it's for APS-C only
3) The new DFA 50 might push down the value of used lenses in the existing lineup.
You can end up a winner in this price vs performance mismatch. I love it, obviously:
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Forum: Pentax News and Rumors
06-27-2018, 06:57 PM
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Well, that's the DA*55, which is a beautiful normal focal length lens on the K-1 and would make for wonderful portraits on your K-S2.
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Forum: Pentax News and Rumors
06-27-2018, 06:52 PM
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Sure.
I know a seriously cashed up Nikon owner - I took a picture with his 600mm f4 on a D500 … but he bought the KP and all of the DA Limited primes because the system looks great and he loved the design philosophy.
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Forum: Pentax News and Rumors
06-27-2018, 04:38 PM
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Well, I think the Zeiss Otis and Sigma Art are 77mm filter sizes, so in theory, more glass again, and better IQ.
D1N0 suggested in the MTF graphic he posted that the Sigma is sharper in the centre, but oddly less so across the frame.
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Forum: Pentax News and Rumors
06-27-2018, 04:13 PM
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The existing FA50 f1.4 and DA* 55 f1.4 are already well within your budget, Ebk.
This thing will be the biggest and most expensive fifty Pentax has ever made.
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Forum: Pentax News and Rumors
06-26-2018, 10:44 PM
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Fictional, surely! :D
Anyway, a date of June 29 was predicted by one member, this brochure reckons July.
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Forum: Pentax News and Rumors
06-26-2018, 09:33 PM
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I'd love to buy a Burmese or Liberian lens!
Okay, 'love' is a strong word. :)
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Forum: Pentax News and Rumors
06-21-2018, 08:20 PM
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I can tell, Paul, you're an Aquarius and like long walks on the beach ...
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Forum: Pentax News and Rumors
06-21-2018, 06:02 PM
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Well, Gm4life said he wants a date ... I've got this cousin, she's recently separated, works out, has a steady job ....
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Forum: Pentax News and Rumors
06-21-2018, 05:02 PM
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What's your source, Zygonyx?
Don't need to name them, just the type ... camera shop owner, Ricoh insider?
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Forum: Pentax News and Rumors
05-24-2018, 04:48 AM
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I would think it would suit your kind of theatrical landscapes very well.
Since floating elements were introduced by Nikon in macro lenses, they perform very well at long distances as well.
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Forum: Pentax News and Rumors
05-16-2018, 03:27 AM
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On the Pentaxians Facebook feed, someone's very proud of their preproduction example:
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Forum: Pentax News and Rumors
04-19-2018, 01:23 AM
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Sure, hats off to 'em, they didn't invent the junction of superficial information and brand sales, they just took advantage of its coming.
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Forum: Pentax News and Rumors
04-18-2018, 11:03 PM
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But I heard that Pentax focus is too poor to get a shot, and the shake reduction has so much noise every pic is a throwaway!
Tony and Ken told me so.
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Forum: Pentax News and Rumors
04-18-2018, 09:22 PM
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We've all got ours, Biz, where's yours? :p
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Forum: Pentax News and Rumors
04-18-2018, 07:21 PM
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The K-01's looks seem to have been inspired by the Transformers. :p
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Forum: Pentax News and Rumors
04-18-2018, 02:41 PM
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Yep, and the one in these * or Opera primes or whatever is different again.
SDM is just a label that's covered different generations and methods of in-lens motors.
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