I am having trouble setting the PDF boxes to my desired dimensions. Suppose I have \setuppapersize[a][b]. I want CropBox = MediaBox = b. So far, so good: I can just use cropoffset=0mm in \setuplayout. But I want TrimBox = a. However, as far as I can see, I can't achieve this using trimoffset in \setuplayout unless (width of b) – (width of a) = (height of b) – (height of a), which does not hold in my case. So it looks like I need to find another way to set the TrimBox (and the BleedBox, which I want to be 3mm wider and taller than the TrimBox). Does anyone know how to do this?

Best,

Jack