Cutting out the 0-255 color diagonal gradients and viewing them with PPaint, there is a loss of color (255 color gradients aren't perfectly smooth), however they look better than I expected, and the color loss in this case could be down to PPaint image handling/conversion process. The 256 color red sphere looks amazing since the banding is less perceptible.
remember that the gradients are restricted to 256 different colors at once. But those 256 colours can be any out of the 24bit.
For 24bit colour RED GREEN and BLUE each can be set at 256 (0-255) levels (intensities)
If you were to use a gradient that used only one of those colours (eg. Black to RED, but not Black to RED to White). In this case you would grantee that you didn't go over the 256 different colours at once limmit. Then it can be displayed in 256 colour AGA with no loss what so ever, as there are only 256 red levels (in 24bit graphics) and AGA can display every one of them.
An ECS or OCS amiga would only be able to display 16 levels of that gradient. 16levels leads to noticeable banding.
In an example where you had a gradient that went from Black to RED to White. You have a situation where you can have 256 levels getting to full red then another 255 levels getting to white.
RED to White is made by keeping RED at 255 and bringing up GREEN and BLUE together.
