注意到ejmartin的测试是在2008年做的。下面是他的原文。有兴趣知道他当年是怎样将ISO100和ISO1600的两张RAW文件合二为一的?

"The exposure was chosen so that the light bulb was just clipping in the ISO 100 exposure, the ISO 1600 exposure was taken just after with the same exposure settings. The two images were then combined at the raw stage, keeping the top four stops of the ISO100 data, ramping between the ISO 100 data and the ISO 1600 data in the next stop down, and then using the ISO 1600 data below that. The raw image was then treated to Bayer interpolation, a rough white balance, and gamma correction (using IRIS, a raw data analysis program)."

太牛逼太有用啦！

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总体感觉还是不如骚泥那种智能分析暗部进行降噪的技术高端啊
如果佳能传感器能加上这项就可以逆天了，因为C的传感器高感DR比骚泥的强一些，只是低感DR中的暗部DR不行

这个太强了。
不过本质还是HDR，只是一次快门出两张曝光不同的图片，后期再合成。
出来的图片不自然，这点应该没法解决了。

突然想到，现在魔灯能控制CMOS逐行不同ISO采样，那如果将来能控制逐行不同采样时间？不知道相机将来支持不。
假如一行使用1/100,ISO 1600,另一行1/1000秒，ISO 100.那动态范围大的没边了

刚才用尼康的RAW尝试了下   把DL开到极高  然后压高光  稍提亮暗部。   和这个效果差不多。

是的，基本上就是给你一个媲美骚泥传感器的RAW文件，提亮拉暗啥的要自己后期去搞

意思是说，开不开dual ISO ，RAW图看起来差不多的，需要自己后期提亮暗部才能体现dual ISO的优势？

Alex这样说：双重ISO的感光度选择要避免高光溢出，如果其中一个ISO的高光溢出，那么这部分细节丢失，无法恢复，这部分图象的最终分辨率减半。

暗部问题不大，细节还在，只是其中一个ISO的图像躁点多些，但（他提供的）软件会处理减少暗部摩尔纹

中间部分（非高光，暗部）没有细节丢失，完整１００％。如果选择的两个ISO接近，比如１００／４００，而不是１００／１６００，那么中间部分更多，分辨率丢失的部分更小，缺点就是获得的动态范围增加部分也小些，达不到３档

最后这句话是重点，这个看样子只有多实践，有经验才行

For full resolution and no moire, you should have detail with both ISOs.  Where one of them gets clipped, you will get half-resolution. If the subject doesn't have fine detail, half-resolution will not be noticeable; but if it has, you will get moire.

In shadows, this is less of a problem; you still have detail in both ISOs, but one of them has too much noise. That detail is usually enough to reduce aliasing, and the algorithm takes care of that. In highlights, if it's clipped, there's zero detail, so you just can't bring back the missing lines.

So, you have to be careful what is covered by both ISOs (OK) and what is covered by only one (risk of moire).

本帖最后由 entersandman 于 2013-8-13 21:51 编辑

想知道这两张图中，图2是电脑后期还是相机直出？如果是相机直出的话，图1也是直出吗？

确实是这样，老镜头的缺陷

6d也能用了，恭喜！这个测试受镜头光晕影响好像效果还不是很好，拍一点别的大反差大光比场景可能效果会更明显。

http://www_magiclantern_fm/forum/index.php?topic=7139.0
目前装这个挺麻烦的，要最新的ML，支持RAW视频的版本的固件，然后再在上边覆盖文件，我6D之前直接用老固件是不行的

谢谢Dulcet大虾的测试！

Dual ISO 不仅无彩躁，而且细节多得多，比较U盘，区别很明显



只是一次爆光，但是传感器部分象素使用ISO１００，另一部分使用其他ISO，如１６００，所以可以拍摄运动题材

这是开发者Alex的原文"
    As expected, intermediate ISOs like 160 or 250 do not cause any changes in ADTG/CMOS configuration. These ISOs are obtained by applying some digital gain to the raw data acquired at the nearest full-stop ISO, and this gain is configured from the DIGIC register 0xC0F08030 (SHAD GAIN). In LiveView, the gain is only applied to the YUV image (it does not affect the 14-bit raw data at all), but in photo mode, the gain is burned into the raw data. Don’t ask me why.

    So, back to our CMOS register #0, it looks like the LSB nibble is probably some flag, and the other two are some sort of amplifier gains. What do you think it will happen if we change this register to 0×403 or 0×043?

    It turns out… the answer to this question is the key to some massive improvement in image quality. The sensor will scan half of the lines at ISO 100 and the other half at 1600 (Figure 2)."

只有８通道相机支持， ５D II， ５D III， ７D， ６D， 看样子７０D也支持.

这个固件和以前所有的Magic Lantern东西都不一样，因为它修改了传感器的硬件工作模式，这发生在整个成像过程整个环节当中很早一环，所以Alex提醒用户目前用小心。

他自己用了几天没出问题，另外有个哥们用Dual ISO拍了两个星期的raw视频，一切正常。

I don’t recommend this for anyone not willing to lose their camera (at least for now). Again, this is not like all of the other Magic Lantern advancements that have come before it. This is a major change in the way the sensor is actually operating. The upside, though, is that it is a very serious increase in dynamic range. This new breakthrough is actually operating in a similar way to how the sensor in the ARRI ALEXA operates. It’s taking dual readouts from shadows and highlights and combining them in a seamless way very early on in the picture pipeline. The reason this is possible, it seems, is because of an 8 channel readout in the Mark III and the 7D, whereas most of the Canon cameras only have 4, so they will not be able to take advantage of this update. The new 70D, however, might actually be able to do it since it supposedly has 8 channels.

本帖最后由 entersandman 于 2013-8-13 21:17 编辑

我只想知道存储速度有无变化

我勒个去。。。高科技来了。