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战斗力 鹅
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你编辑过后的内容真够恶心的，忍不住，我回你我再自抽
又玩删删节节下三滥的断章取义，你不要再侮辱原作者了行么？
http://www.luminous-landscape.co ... olling_review.shtmlIt should be fairly obvious that if you have two sensors of the same size, one with 16 Megapixel and one with 24 Megapixels, the one with the lower pixel count will, all other things being equal, have lower noise. The reason is simply physics; the pixels are larger and therefore collect more photons. More photons means a higher S/N ratio.
Below I have taken the NEX-7 files and resampled them down to the same size as the NEX-5n files. Bicubic Sharper in Photoshop CS 5.1 was used. The argument goes that if a larger file is downsampled its noise will similarly be reduced along with its resolution.
最后得出的结论你怎么不贴？If you scroll back up to the top of the comparison samples, or click here, and then scroll down the ISOs you'll see that up to and including ISO 800 there is little to choose between the two cameras, even given their resolution disparity. At ISO 1600 and above, the NEX-5n starts to have a small but clear advantage in terms of noise performance.
But, and it's a very big but, now go to the top of the samples where the NEX-7 files have been downsampled to the same size as the NEX-5n. What you'll see, or at least what I and several other photographers to whom I've shown these agree on, is that the differences are reduced to a quibble, even at 100% on screen. In prints or any non-pixel-peeping use of the images, there is really little to choose between them, except maybe at ISO 12,800 where the 5n has a slight advantage on screen, if not in real-world prints. Like I said – a quibble.
What this means is that in practical terms, the NEX-7 gives the photographer the choice of higher resolution and larger prints, or comparable resolution and comparable noise characteristics when compared to the NEX-5n, and both are presented at the same size. I should add parenthetically then in real-world photography, when shooting raw and doing a bit of NR in Lightroom, all ISOs up to and including 3200 are completely usable for most any purpose.
f you'll allow, I'll also make a small editorial comment on the whole question of high ISO noise. In my opinion too many people on brand discussion forums make too big a deal about high ISO noise. I suppose that it's one of those things that lends itself to easy visual comparison, while topics such as dynamic range, colour gamut and fidelity are more complex, and less easily quantified outside of a lab. Fine then, if debating is the point. But in reality just about every current generation DSLR and CSC on the market today is capable of such good high ISO performance along with the assistance of a bit of raw file NR, that the debate is likely of greater interest to its participants than most photographers who are more interested in actually doing photography. Stick to ISO 3200 or less in raw, use a bit of post NR, and work with a fast lens. Black cats in coal mines will have nowhere to hide.
DxO发布测试结果后作者的更新内容：DxO's numeric analysis almost exactly matches my subjective evaluation above, which, whether you're a DxO Mark "believer" or not, at least adds some additional corroboration to each of our analysis. Once again, the bottom line – when normalized for image size – the NEX-7 and NEX-5n have essentially similar noise performance.
本来是有参考价值的文章，删前删后扯，能再恶心一点么？
我一开始回你我就是傻逼，跟你码那么多字简直是超傻逼 |
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楼主: snfeng
沪公网安备 31010702007642号 )
发表于 2012-10-11 11:06
如你所说，dxo不是给一般用户在实际使用提供参考的，那你前面拿dxo出来是卖萌的么？
各种打脸后，还要用混淆概念这种傻逼战法不屈不挠往上贴，某自称傻逼的家伙唾面自干的能力够不够强力？
，可惜相机厂商但凡出款像样的新机，首先放出的都是100%raw样张，为啥人家不学形单影只的dxo弄个8mp缩图敷衍一下呢？
我太高估你了
