![]() ![]() So in the highlights we have "minus green" situation, and the common name for "minus green" is purple. This means Rmax will be multiplied by 2x and than limited to the tag value, 27850 similarly, Bmax will also be limited to 27850 but G in fact reaches only 26193. ![]() To calculate white balance multipliers from it, take the reciprocal values of the "As Shot Neutral" tag, meaning R is about 2x, B is about 1.13x, and G stays at 1x. For the particular shot, we are interested in "As Shot Neutral" tag, which reads R=0.5085 G=1 B=0.8843. The multiplier for the green channel(s) is usually 1x, or very close to 1x. By the way, you can check the DNG tag value right in RawDigger - press the EXIF button in the upper left part of the RawDigger screen and scroll down a little.ĭigital cameras also use white balance, which is 3 or 4 multipliers applied per respective RGB(G) channels. In my case it looks like this:Īs you can see, highlights are magentish and the lowest maximum value (marked with green arrowhead) is 26193 it happens to be for the second green channel, G2. Now to check the actual white level value, download a free trial of RawDigger from and open the same dng file. This means that the white level in the file is supposed to be 27850. With exiftool, the command line isĮxiftool -S -H -WhiteLevel your_dng_filename.dng or one of the GUIs that are listed closer to the bottom of the page. To see the value of the tag for your camera, download and install the free command-line utility called exiftool /~phil/exiftool Saturation is caused either by the sensor itself becoming highly non-linear in response, or by the camera's analog to digital converter clipping." The DNG standard calls this value "White Level" and explains it this way: "This tag specifies the fully saturated encoding level for the raw sample values. Sometimes it is called "saturation", but it is a bit of misleading term, especially if ISO is raised. Thus it also exhibits magenta highlights.Ĭan you please explain what do you mean for "calibration, maximum, tag reads"? Is there a procedure I have to do?ĭigital cameras have the maximum raw value that can be reached (highlights). On one of the samples I have the real maximum is 26193, while the tag reads 27580. Iliah Borg wrote:The problem is most probably the calibration. Film mode allows a LOT of the overexposure to be tamed down during the color correction pass. All shooting used Film Color Space, which, with the last Final Cut X upgrade, is EXTREMELY simple to process, as the conversion is built in. Because it has a bulging front lens, it will take a unique little rig to get the variable ND on it. Its shortcoming is that it has a limited f/stop range, stopping at f/11. The Kowa, a one inch sensor format lens from the machine vision world (where most camera sensors come from) is spectacular. The shooting was with a Metabones speed booster on a 17-35 Nikkor and a decent variable ND filter at ISO 800, and when darkness allowed, a Kowa 6mm f/1.8 via a Metabones C to M43 mount. When the show is done with scoring and final color work, you will be able to find it on YouTube titled "Cross Country at 14,000 MPH." I don't really see any magenta in the blown out highlights. I just reviewed five days' worth of footage shot with my Pocket Cinema Camera with loads of overexposure, as when shooting a trip due west from Florida to California on the I-10, shooting the sun is inevitable. ![]()
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