The compensating effects of Rodinal at higher dilutions are well known. I review them in my article on Appreciating Rodinal in the Articles section of my site at http://unblinkingeye.com. Rodinal does not have any solvent action on film grain, so whatever grain structure the film has will be retained, but the overall effect is one of high acutance, particularly with large format. I recommend starting with a dilution of 1:100.(posted 8978 days ago)Another popular solution among fine art photographers is Gordon Hutchings' PMK pyro formula, which I cover in my article on mixing developers. Because pyro developers produce some of their density with stain, the highlights typically remain transparent and can therefore be printed, producing a remarkably luminous quality in the print. Gordon Hutchings' THE BOOK OF PYRO is definitive, and he gives times for N+ and N- developments for most popular films.