Re Filters in Iray

Prince Wao

What, technically, is the difference between the various filters?

Due to having a composition which is hitting record length rendering times I've been doing experiments with various settings - plus I've bought a very unhelpful tutorial and had a look at free ones on YT - but nothing I've tried makes any difference. Doing 'short' spot-renders of the entire scene for speed I've tried each of the filters and while I can see no difference between the finished renders, Triangle renders a few seconds faster than the rest - the rest doing the same amount of iterations in the same amount of time. So, what actually is the technical difference between the filters?