{"id":1041,"date":"2021-11-25T09:40:17","date_gmt":"2021-11-25T01:40:17","guid":{"rendered":"http:\/\/blog.fengyu-poi.cn:57650\/?p=1041"},"modified":"2022-08-19T22:50:45","modified_gmt":"2022-08-19T14:50:45","slug":"s-log%e9%82%a3%e7%82%b9%e4%ba%8b","status":"publish","type":"post","link":"http:\/\/www.fengyu-poi.cn\/?p=1041","title":{"rendered":"\u3010\u4e00\u70b9\u70b9\u8272\u5f69\u79d1\u5b66\u3011S-log\u90a3\u70b9\u4e8b"},"content":{"rendered":"

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\u767d\u76ae\u4e66\u539f\u6587\u5730\u5740<\/h2>\n\n\n\n
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Slog1<\/a><\/div>\n\n\n\n
Slog3<\/a><\/div>\n<\/div>\n\n\n\n

\u8bbe\u8ba1\u8bf4\u660e<\/h2>\n\n\n\n
The S-Log gamma function is optimized for Digital Motion Picture camera. The logarithmic camera encoding curve was carefully designed by analyzing the noise floor characteristics and the tonal reproduction of the imaging device. Since negative film stock and the CCD or CMOS imager behave differently to incoming light, especially in the low-light and high-light region, the S-Log curve differs from Log curves for film based images. CCD or CMOS imagers respond to incoming light in a far more linear fashion than film, thus there are no \u201ctoes\u201d or \u201cshoulders\u201d. The S-Log curve provides sufficient quantization bits to offer exceptional tonal reproduction in both the low-light and high-light region. The appearance on a monitor is also taken into consideration, so that an S-Log image could be viewed using an appropriate display LUT (Film Print Emulation and\/or S-Log to Rec 709). When shooting in S-Log, as distinct from ITU-R BT. 709 (Rec 709) video gamma, a color grading (\u2018look management\u2019) process is mandatory to establish a desired reference \u2018look\u2019 (color; contrast) for dailies and editorial. This color graded \u2019look\u2019 should be related to a target output display, e.g., film print projection; digital cinema projection. When viewing S-Log encoded images on an HD reference monitor that are ultimately intended for cinema release via film print and D-cinema projection, a display LUT should be applied that emulates film print or digital cinema color and contrast within the constraints of the video monitor\u2019s gamut and contrast. Using the traditional photo-chemical analogy, S-Log is the \u201ccamera negative\u201d and the final look of the \u201crelease print\u201d and DCP is ultimately defined during the final color grading in the Digital Intermediate post production process.<\/pre>\n\n\n\n
\u548c\u5176\u4ed6Log\u4e00\u6837\uff0cSlog\u6574\u4e2a\u7cfb\u5217\u7684\u8bbe\u8ba1\u521d\u8877\u662f\u4e3a\u4f18\u5316\u6570\u5b57\u4f20\u611f\u5668\u7684\u7f16\u7801\u4f53\u7cfb\u7684\uff0c\u5e76\u5728\u9634\u5f71\u548c\u9ad8\u5149\u7684\u8d44\u6e90\u5206\u914d\u95f4\u53d6\u5f97\u5e73\u8861\uff0c\u540c\u65f6\u6700\u5927\u7a0b\u5ea6\u5229\u7528\u4f20\u611f\u5668\u7684\u52a8\u6001\u8303\u56f4\u3002<\/p>\n\n\n\n
\u6ce8\u610f\uff0cSlog\u63d0\u51fa\u4e5f\u6709\u8ba9\u6570\u5b57\u6444\u5f71\u673a\u753b\u9762\u9002\u914dCineon\u5de5\u4f5c\u6d41\u7a0b\u7684\u521d\u8877\uff0cArri LogC \u5728\u8bbe\u8ba1\u65f6\u4e5f\u6709\u8003\u8651\u8fd9\u4e00\u70b9\u3002<\/p>\n\n\n\n
Slog3\u7684\u63d0\u51fa<\/h2>\n\n\n\n
F65, F55 and F5 will add two new color grading spaces, \u201cS-Gamut3.Cine\/S-Log3\u201d and \u201cS- Gamut3\/S-Log3\u201d. This document provides a technical summary of the new color grading space for people who are familiar with Log Base Grading.\n\u201cS-Gamut3.Cine\/S-Log3\u201d is designed for more like pure log workflow. Color space is similar to negative film scan which is used for TV production, film out and digital cinema. Color reproduction is designed slightly wider than DCI-P3 to provide ample room of grading. Tone curve is more like pure log encoding characteristics preserving more tonal gradations in the blacks, and has good compatibility with Cineon workflow.\n\u201cS-Gamut3\/S-Log3\u201d is very close to camera native color, and is very good for archiving as a digital camera negative, as 8\/10\/12bit code value. Color space of S-Gamut3 is kept the same area of original S-Gamut, though color reproduction inside S-Gamut3 is more accurate than S- Gamut.\n<\/pre>\n\n\n\n
\u8fd9\u91cc\u63d0\u5230S-Log3\u201d is designed for more like pure log workflow. \u5373Slog3\u6bd4\u524d\u4ee3\u300c\u66f4\u52a0\u5bf9\u6570\u300d\uff0c\u6574\u4e2a\u66f2\u7ebf\u66f4\u52a0\u5e73\u6ed1<\/p>\n\n\n\n
\u6211\u4eec\u8fd8\u80fd\u6ce8\u610f\u5230 S-Gamut3\u8bbe\u8ba1\u65f6\u8003\u8651\u4e86\u6444\u5f71\u673a\u7684\u672c\u8eab\u8272\u5f69\u7279\u6027\uff0c\u53ef\u4ee5\u8bf4\u662f\u91cf\u8eab\u5b9a\u5236\uff0c\u80fd\u591f\u6700\u5927\u7a0b\u5ea6\u4fdd\u7559\u4fe1\u606f\u3002<\/p>\n\n\n\n
Why S-Gamut3.Cine<\/h2>\n\n\n\n
S-Gamut3.Cine is similar to negative film scan which was used for TV production, film out digital cinema. Color reproduction is designed slightly wider than DCI-P3 to provide ample room for grading. Thus manual grading for P3 becomes easier. S-Gamut3.Cine is more convenient to grade than S-Gamut3 and S-Gamut as camera digital negative.\nIf you would like to apply print film emulation, please increase saturation to about 1.4. Sony also provides .cube files (Look Profile) to convert 709 video color space.\n<\/pre>\n\n\n\n
\u4e4d\u4e00\u770b\u8fd9\u53e5\u8bdd\u8bf4\u7684\u5f88\u62bd\u8c61\uff0c\u4e0d\u8fc7\u5f53\u6211\u4eec\u628a\u8fd9\u4e24\u4e2aGamut\u653e\u5230CIExy\u56fe\u4e0a\u4e4b\u540e\uff0c\u5c31\u4e00\u76ee\u4e86\u7136\u4e86\uff01<\/p>\n\n\n\n