99 percent of my printing is 36"x44" poster size printing. I work for a university and print all of the posters for scientific presentations. I often take an image straight from a Nikon D100 (3008x200px) into a photoshop (PSD) sized 36x44 @ just 100 dpi and the prints are absolutely perfect. I have an Epson 9600 printer, the same as my local digital print shop (www.murphyscamera.com
). I spoke to one of the guys there two weeks ago and he said they print at 100dpi on the 9600 as well. There is really no signifigant gain in printing at higher than that when creating poster sized prints. The paper choice DOES
however make a difference. I typically use epson premium lustre photo paper (as does Murphy's) and the prints are great. If I use the 9600 to print 11x14's I jump up to 300dpi, but I get the same image quality at 100dpi on the large prints.