Has anyone tried making negatives for alt. process work using Fujiclear or Duraclear RA4 material? My only concern is whether or not the dyes are opaque to UV (some inkjet inks, for example, are not). So far I have no been able to find spectral density curves below 400nm, but it does look like density begins to rapidly increase for yellow and cyan dyes at this point, the question is just how far does it go into the UV? Would there be an optimal negative "color" to ensure the best results?