On Sun, Aug 15, 2010 at 2:09 PM, Ann Sanfedele <[email protected]> wrote: > Is there any point to display an image on line at 300 PPI as opposed to 72 > (or 96) with the same outside dimensions of, say > 1200 x 800 ? Or as .png as opposed to jpg ?
In most browsers and image viewing applications, the density setting is ignored so whatever pixel dimensions you set is all that matters. Some applications, usually graphics and page layout apps, honor the density setting in images. PNG (Portable Network Graphics) is a losslessly compressed image file format that was designed to improve upon the proprietary GIF format (owned by CompuServe). There's a good discussion of it on Wikipedia at http://en.wikipedia.org/wiki/Portable_Network_Graphics It's at its best for use with graphic images, not photographic images. JPEG and the little-used JPEG-2000 are better formats for photographic images. > Yet it seems to me that some images you guys pointing to 1 mg to 3 mg files > on line do look "better"... on my LCD monitor... It's all a matter of how well they are rendered for the display and how the software you're using to view them handles the display rendering processing. > Almost all the files I send to smugmug are 300 ppi/dpi and 12 inches across > - and a few mgs... but I don't know if > the site translates them to show them on my site at a lesser resolution. For printing, a 240 to 360 ppi density image at the on-paper dimension is the right thing to do. For display on the web, I usually set the image size to fit in a box about 800x800 in size. I set the density to 72 because at that density on an 800x800 pixel image, Photoshop renders my annotation text to the pixel dimensions that looks good, to my eye. -- Godfrey godfreydigiorgi.posterous.com -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
