TBC it depends on how/why you are out of the range 0 .. 255. Pixel values greater than 255 are no problem, you just won’t get the color weight you might think. 256, e.g. would be seen as 0, 257 as 1 and so forth.
-1 gets changed to 255 when passed to a function where the corresponding parameter is unsigned char. So here’s full bright when you might think almost totally off.
Another cause of smart LED excitement is not correctly specifying the strip type and order of the (W)RGB components. Not an issue here.
a7