Ok, here are a few tests I've done. I'll preface this by saying that for "pure" arch viz stuff, or things where very sharp edges are absolutely needed, it's best to render bigger and reduce... however, for photo's and such where you want to make a poster size, etc., I feel that the results are very, very accpetable (to me anyway)... I'm having two "art prints" done that have been blown-up and I am very happy with the results. Anyway, here are a few tests (sorry for the large picture sizes):
Original: 8x7.5" @ 72dpi
Size 32x30" @ 72dpi - no sharpening
Size 32x30" @ 72dpi - 50% sharpening
Size 32x30" @ 72dpi - 100% sharpening
Size 32x30" @ 300 dpi - no sharpening (only link - it's over 1Meg in size)
Don't forget, if your browser automatically resizes pictures to fit the screen, use the little "four corner" icon that pops up in the lower right hand corner to make the image full size...
http://jfww.com/maxwell/blowup/sam_32_30_300dpi.jpg
Art print examples:
Original 15x15" @ 72 dpi (notice jaggies along orange <?> edge}
23x23" @ 200 dpi - no sharpening (jaggies gone)
Now, I agree that they get a little "soft", but for a blow-up to poster size for family pictures and such, and from a couple of feet away (unless you LIKE looking at photo's from a few imches) I find this to be perfectly acceptable. Perhaps not magazine print quality, but damn good.
Lastly, check out Cafe Press... you can get all kinds of things printed for gifts etc., and they'll do one (1) item! I just had two large posters done...
http://www.cafepress.com
