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10-26-2017, 01:51 PM - 1 Like   #1846
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QuoteOriginally posted by ffking Quote
so far - I was partly interested as AW would imply internal zoom/focus, WR not
The DFA150-450 is both AW and extending zoom, so this doesn't apply.

10-26-2017, 08:12 PM - 6 Likes   #1847
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---------- Post added 10-26-17 at 08:19 PM ----------

10-26-2017, 10:23 PM   #1848
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KAF4 ...

No love for my K5.
That's fine, it'll change into a K-1 some day...
10-26-2017, 11:37 PM   #1849
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On the last image one can see that it has the filter diameter 72 mm.

10-26-2017, 11:47 PM   #1850
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QuoteOriginally posted by ffking Quote
I notice that it was the same minimum focusing distance as the Sigma 50mm f/1.4 Art - must be a rebadge
And how would You explain that long shipment period?
10-27-2017, 12:07 AM - 1 Like   #1851
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QuoteOriginally posted by x4rd Quote
And how would You explain that long shipment period?
Maybe they couldn't get the word Pentax to fit in the space where it used to say Sigma - it's a letter longer, after all
10-27-2017, 01:31 AM - 1 Like   #1852
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Huuuuuuuge! I am sure the performance will also be!

10-27-2017, 01:59 AM - 3 Likes   #1853
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QuoteOriginally posted by stevebrot Quote
Given the length and girth and depth of the hood, I would have guessed a fast 85
Perhaps the hoods are interchangeable between the FA*50mm f/1.4 and the FA*85mm f/1.4, pentax has a history of doing that.

QuoteOriginally posted by grahame Quote
Sigma copy in fact: huge, heavy. not pentax any more
And this assertion is based upon what evidence?* Extraordinary claims require extraordinary proof, I know I am not alone here: I want citations.

* If you are going by the similarity of the minimum focus distance between the Sigma 50mm f/1.4 ART and the Pentax D-FA 50mm f/1.4 which I'll admit is unique among fast standard Pentax 50mm primes [ which have been typically 0.45m or 1.5ft] - doesn't make it a FACT it is a Sigma re-badge. Unlike the infinity focus point which is governed by the lens mount flange distance. Minimum focus point in regards to optical design is largely arbitrary [ and also subject to the reduction of image quality that is deemed "acceptable" by the optical engineers] you could make a 50mm f/1.4 lens focus to 1:1 if you really wanted to. However, the intensity of illumination at the focal plane will be diminished greatly at such a focus distance due to the cos4 law so a T=1.4 lens at infinity would behave more like a t=4.8 lens at 1:1. With a loss of approximately 1/8 a stop as you move outwards from the center portion of the image circle... which would make the amount of vignetting slightly worse than the existing DA*55mm f/1.4 @ infinity on the K-1.

Last edited by Digitalis; 10-27-2017 at 02:42 AM.
10-27-2017, 02:10 AM - 3 Likes   #1854
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QuoteOriginally posted by blende8 Quote
On the last image one can see that it has the filter diameter 72 mm.
And the Sigma 50 1.4 Art has a filter diameter of 77mm, so we can probably put that rumour to bed...
10-27-2017, 04:43 AM - 1 Like   #1855
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10-27-2017, 04:50 AM - 1 Like   #1856
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DA★ ==> wrong thread
10-27-2017, 06:08 AM   #1857
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It's huge... is that a function of th ring motor?
I'm used to 50s I can slip in my pocket.

DFA* is clearly visible in the first image,
10-27-2017, 06:26 AM   #1858
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QuoteOriginally posted by normhead Quote
Given the life of these lenses, a year is nothing. Everyone complains because there are no Pentax announcements and Pentax doesn't tell us what they are doing. Then when they do announce early, we claim a year is too long to wait. It doesn't matter what Pentax does, its not good enough for some members of the forum.
Considering that these are lenses that should have been available at the time the K1 became available, yes, this is far too long a wait.
10-27-2017, 06:40 AM - 1 Like   #1859
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Nobody managed to launch a system with all lenses "that should have been available". Sony barely had 5 lenses...
10-27-2017, 08:04 AM - 1 Like   #1860
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QuoteOriginally posted by Kunzite Quote
Nobody managed to launch a system with all lenses "that should have been available". Sony barely had 5 lenses...
Even less than that:

- two APS-C lenses at NEX-3 and NEX-5 launch (16mm f/2.8 and 18-55mm f/3.5-5.6)
- two 24x36 lenses at Alpha 7 and Alpha 7R launch (24-70mm f/3.5-5.6 and 35mm f/2.8) plus two available one month afterwards (55mm f/1.8 and 24-70mm f/4); as for the fifth one (70-200mm f/4), announced together with the four others, price and availability were tbd at the time of the announcement.

Same for Hasselblad X1D-50c, Fujifilm X-Pro1, Fujifilm GFX-50S and more.
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