This is a two-day color-enhanced composite from GOES-16 taken June 2-3, 2017 (17:45:00 UTC) with simple cloud reduction processing. The individual image bands were provided by SSEC RealEarth.
It uses bands 1, 2, and 3 to generate a synthesized green band. I duplicate the blue channel and add the red channel and near-infrared channel as new layers with their opacities set to 45% and 5%, respectively. These percentages may or may not be ideal but it's what I work with. The resulting very bland RGB composite will require additional processing.
There is a more sophisticated and accurate method for creating a green band that uses a color lookup table (LUT) derived from red, green, blue, and near infrared bands from other sensor platforms like Himawari 8, MODIS, and VIIRS but it is not used here.
Unlike the images in the previous post, a modified "natural color" layer made using bands 2, 3, and 5 was added. Normally "natural color" images using similar bands show snow and glaciated clouds in cyan.
To minimize the cyan, band 2 was added as a layer over band 5 with the blend mode set to lighten before all three channels were combined to produce a RGB composite.
This does introduce some magenta coloration in snow and, most notably, the shallow salt lakes in Utah. For the purpose of this image it is a lesser evil. It could probably be minimized or eliminated with further pre-processing.
[Added June 8, 2017] To eliminate the magenta I use the modified image as the base layer then add the cyan-colored version as a new layer with the blend mode set to hue. (All three images shown have a multiply blend mode applied as is typical for "natural color" composites.)
To reduce the presence of clouds the second day image was overlaid onto the first day image and the blend mode was set to darken. This will leave cloud shadows artifacts if a cloud mask is not used (one was not used here). I plan to update the top image with additional days added until I have a mostly cloud-free result.
I have not detailed every step used to create the final image for a few reasons. A couple of the color adjustment layers are luminance-specific and will fail when the affected areas become too dark, like earlier or later in the day. The image was created using the venerable but largely forgotten JASC Paint Shop Pro 6.02 so it's not easily reproducible. Finally, I'm not entirely satisfied with the results so it's still very much a work in progress.
CREDIT
NASA
National Oceanic and Atmospheric Administration (NOAA)
Space Science and Engineering Center (SSEC) University of Wisconsin-Madison
 |
| Credit: NASA / NOAA / SSEC - Modified by LoneSky. |
It uses bands 1, 2, and 3 to generate a synthesized green band. I duplicate the blue channel and add the red channel and near-infrared channel as new layers with their opacities set to 45% and 5%, respectively. These percentages may or may not be ideal but it's what I work with. The resulting very bland RGB composite will require additional processing.
 |
| Credit: NASA / NOAA / SSEC - Modified by LoneSky. |
There is a more sophisticated and accurate method for creating a green band that uses a color lookup table (LUT) derived from red, green, blue, and near infrared bands from other sensor platforms like Himawari 8, MODIS, and VIIRS but it is not used here.
Unlike the images in the previous post, a modified "natural color" layer made using bands 2, 3, and 5 was added. Normally "natural color" images using similar bands show snow and glaciated clouds in cyan.
 |
| Credit: NASA / NOAA / SSEC |
To minimize the cyan, band 2 was added as a layer over band 5 with the blend mode set to lighten before all three channels were combined to produce a RGB composite.
 |
| Credit: NASA / NOAA / SSEC - Modified by LoneSky. |
This does introduce some magenta coloration in snow and, most notably, the shallow salt lakes in Utah. For the purpose of this image it is a lesser evil. It could probably be minimized or eliminated with further pre-processing.
[Added June 8, 2017] To eliminate the magenta I use the modified image as the base layer then add the cyan-colored version as a new layer with the blend mode set to hue. (All three images shown have a multiply blend mode applied as is typical for "natural color" composites.)
 |
| Credit: NASA / NOAA / SSEC - Modified by LoneSky. |
To reduce the presence of clouds the second day image was overlaid onto the first day image and the blend mode was set to darken. This will leave cloud shadows artifacts if a cloud mask is not used (one was not used here). I plan to update the top image with additional days added until I have a mostly cloud-free result.
I have not detailed every step used to create the final image for a few reasons. A couple of the color adjustment layers are luminance-specific and will fail when the affected areas become too dark, like earlier or later in the day. The image was created using the venerable but largely forgotten JASC Paint Shop Pro 6.02 so it's not easily reproducible. Finally, I'm not entirely satisfied with the results so it's still very much a work in progress.
CREDIT
NASA
National Oceanic and Atmospheric Administration (NOAA)
Space Science and Engineering Center (SSEC) University of Wisconsin-Madison
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