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Summilux 28mm月底發佈

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發表於 2015-5-23 10:26:28 來自手機 | 顯示全部樓層
Assume 21,24,28lux are at similar price tag, and you are going to get only one of those, which one would you guys get? And why?

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發表於 2015-5-23 10:48:45 | 顯示全部樓層
好大支...
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發表於 2015-5-23 11:39:13 | 顯示全部樓層
28/1.4A corner vignetting could be a major concern for many. We may not be able to notice the problem looking at the published pictures as they are corrected while some are heavily processed.
When the 28/2A was launched, many users complainted at its 2 stops vignetting (at max aperture of f2 on 35mm full frame).
For 28/1.4A at f1.4, the "dark corners" are at 3.5 stops (on 35mm full frame) and 2 stops even on APSC size sensors (like M8).
Some may like this as an effect at certain situations but many won't. The vignetting will be very noticable at f1.4 unless corrected by camera built-in lens profile or pp afterwards.

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I'm having a hard enough time post-processing 28/2A. Imagine 3.5 stops vignetting!  發表於 2015-5-23 21:25
x2 agree! Vignetting creates a totally new ball game if one needs even lighting across the field. Post-processing will become a major challenge!  發表於 2015-5-23 21:24
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發表於 2015-5-23 13:33:11 來自手機 | 顯示全部樓層
Gone were the days when E49 28mm elmarit-M with oversized front lens elements to mitigate the vignettes issue. Max light loss is 1.9 stops.... But now, 3.5 stops seems a challenge to post processing software.
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發表於 2015-5-23 14:15:49 | 顯示全部樓層
頭文字L 發表於 2015-5-23 13:33
Gone were the days when E49 28mm elmarit-M with oversized front lens elements to mitigate the vignet ...

When 28/1.4A stop down to f2.8, it is actually very close and seems slightly better than the E49 28mm Elmarit (version 3). The 3.5 stops of vignetting is at f1.4
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發表於 2015-5-23 14:56:50 來自手機 | 顯示全部樓層
M3fans 發表於 2015-5-23 14:15
When 28/1.4A stop down to f2.8, it is actually very close and seems slightly better than the E49 2 ...

Consider MTF wise, 28mm summicron is still the lens to beat amount the current three 28mm in Leica stable.
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發表於 2015-5-23 17:16:06 | 顯示全部樓層
有理由相信不久將來Leica會停產支Summicron 28mm,唔係支Summilux 28mm點賣。
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發表於 2015-5-23 19:16:52 來自手機 | 顯示全部樓層
本帖最後由 頭文字L 於 2015-5-23 19:18 編輯

From rapid drop of MTF values near format edges, I guess the image circle of 28 lux is not as large as the summicron. So as from the vignette diagram ... Moreover, separate of T and S resolution lines may implies chromatic errors may easily occurs ?

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Same issue for Lux 21, 24, 28, 35. The shorter the focal length, the more severe the problem.  發表於 2015-5-23 21:31
The optimal plane of focus is not flat. Moreover, at the edges the optimal plane of focus diverges for sagitial and tangential light, particularly for the fine details.  發表於 2015-5-23 21:29
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發表於 2015-5-30 12:34:57 | 顯示全部樓層
28 Lux .... M8 / 8.2 因物
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發表於 2015-5-30 15:26:40 | 顯示全部樓層
頭文字L 發表於 2015-5-30 12:34
28 Lux .... M8 / 8.2 因物

haha, thinking about this lens all the time? Buy one la
And seriously, one should reconsider as the technical data was recently modified, seems Leica noticed some earlier mistakes.
Now, the MTF charts are replaced with much better ones.
Data now shows more distortion but the vignetting chart still shows the same light lost and still has f2 instead of f1.4
If this set of data is real and final, 28/1.4 should be better than or at least equal to 28/2 in the center up to the shorter sides of the frame, ie 28/2 only has advantage at the far corners and longer sides of the frame. Also, of course the weight and size.
These mistakes all over the 1st published technical page is just plain lousy!

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yes it is "on paper" that I am talking about, on the Leica official site, one can look at or download technical data of lenses in pdf format  發表於 2015-5-30 22:50
kgv
You mean the lens structure has changed, or it's just simply stupid errors "on paper" in the initial announcement?  發表於 2015-5-30 21:05
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發表於 2015-5-30 20:54:39 來自手機 | 顯示全部樓層
M3fans 發表於 2015-5-30 15:26
haha, thinking about this lens all the time? Buy one la
And seriously, one should reconsider as th ...

First set of MTF has less distortion.... Stainless steel version has 1st data sheet ? Black version got redesign?

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can't answer your questions but what I am talking about is the technical data file of the lens on the official Leica site in pdf fomat that can be looked at or download  發表於 2015-5-30 22:52
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