@jdc Jacques, it looks like there’s a limit to the RT-spot size (1500 each side). I think it can be too small in some cases. I don’t know if the size is set to be proportional to the image size, or if it’s constant: what if we use a 100 or 150 Mpixels file?
Another suggestion: when I set a spot in inverse mode to create some sort of vignetting, some artifacts can be visible (look at the edges of the tree in the 4th picture here.
Maybe a “scope” slider would be be useful also in inverse mode in such cases ?