label = "Blue: ";
blue = doProjections(blue);
if (blue==null || done) return;
blue.hide();
int w = red.getWidth(), h = red.getHeight(), d = red.getStackSize();
RGBStackMerge merge = new RGBStackMerge();
ImageStack stack = merge.mergeStacks(w, h, d, red.getStack(), green.getStack(), blue.getStack(), true);
new ImagePlus("Projection of "+imp.getShortTitle(), stack).show();
}