05-27-2020, 06:06 AM
These weird black pixels are out of gamut pixels (pixels with negative values).
Use the Color Picker and observe the values in the info window.
In the case of Drop shadow, it happens when the opacity value is higher than 1.0.
You can get rid of them by using Colors > RGB Clip...
Out of gamut pixels only exists for floating point precision image, where pixels can take any value.
In integer precision, pixel values are automatically clip to a positive range, e.g. [0, 255] in 8bits.
Use the Color Picker and observe the values in the info window.
In the case of Drop shadow, it happens when the opacity value is higher than 1.0.
You can get rid of them by using Colors > RGB Clip...
Out of gamut pixels only exists for floating point precision image, where pixels can take any value.
In integer precision, pixel values are automatically clip to a positive range, e.g. [0, 255] in 8bits.