Julie, Whether you "scale up" or increase resolution (ppi or "dpi") you will be increasing the amount of pixels being created. The one thing you want to focus on when scanning is the pixel dimensions. Everything else will be determined from those dimensions. ppi or dpi is applied to the origianl pixel dimensions. Scalling up the image 200% increases the pixel dimensions. No matter what controls you use while scanning, pixel dimensions determine what your final output will be. If its a 5x7 image you will scan and you want to print it at 200% of its origianl size at 300ppi, the pixel dimensions will be 3000pixels x 4200pixesl, allowing you to create a 10x14 @ 300ppi print from the original scan without having to interpolate the image up. With the same scan you can print an image at 5x7 @ 600ppi or 3x5 @ 1000ppi. Of course you would probably resize the image down for printing at those dimensions 5x7 @ 300ppi and 3x5 @ 300ppi. Depending on the purpose of your larger print, if it were to be a poster, you can go larger still by interpolating your original file to produce even larger images. Of course as you interpolate up you begin to loose quality, but you can judge at what point you have reached your limit. No matter how you scan the image, if its going to be larger than the original it will loose some qualities the original has at its 5x7 size. Hope this helps. Feel free to contact me. Mike Rippy IMA Photographer mrippy at ima.museum (317)920-2662 ext.191 IMA 4000 Michigan Road Indianapolis, IN, USA 46208-3326 www.ima.museum
>>> jgrob at uh.edu 11/21/2006 4:32 PM >>> Hello, We are about to begin scanning a large group of early 20th century negatives. They are about 3.5" square. We will be creating master TIFFs of course, but we would like to be able to print larger than 3.5" images. Is it better to scale up and scan them at something like 200%, or to increase the resolution from 600 dpi to a higher dpi? Thanks in advance, Julie Grob Julie Grob Digital Projects and Instruction Librarian Special Collections 114 University Libraries University of Houston Houston, TX 77204-2000 (713) 743-9744 jgrob at uh.edu _______________________________________________ You are currently subscribed to mcn-l, the listserv of the Museum Computer Network (http://www.mcn.edu) To post to this list, send messages to: mcn-l at mcn.edu To unsubscribe or change mcn-l delivery options visit: http://toronto.mediatrope.com/mailman/listinfo/mcn-l
