Since the early 90's and the introduction of desktop photo-imaging, error diffusion has continued to be used as the primary FM screening method for photo-inkjet printing. Modern error diffusion algorithms continue to deliver stunning photo quality but the nature of the algorithm makes it calculation intensive and inherently slow. Much work has been done over the years to try and improve the performance of error diffusion. As a result of this work and modern hardware configurations, contemporary algorithms operate at significantly increased speeds (and image rendering quality) when compared to similar developments from the late 80's and early to mid 90's. The fact is though that however many optimisations are applied to the algorithm, a simple point process system such as that employed with a threshold array will always exhibit better performance when compared with an equivalent error diffusion algorithm operating on the same image data.