Wednesday, February 22, 2012
2012: ENLARGING IMAGES
A number of visitors as well as a number of attendees at my history programs have made me aware of an incredible site for beautiful specimens of postcards; especially Mercer County and the Trenton area. My numerous on screen slide programs require large images that lend themselves to enlarging in my Photoshop software program. On screen graphic display is a somewhat tricky and perhaps confusing process. Recently, I posted the lithograph of Mercer Hospital from my classmate Alice Schmidt Mullen. It was scanned at 300 dots per inch which allows for exponential enlarging without losing too much detail. Many visitors are aware of www.usgwarchives.org who have an incredible archive of postcards from all over the U.S. These are all displayed at 72 dots per inch, which, as you can see by the graphic in the upper right loses its clarity when attempts are made to enlarge it from its original print size. (If you right click on the entire graphic and choose "open link in new window" enlarge the images, you will see that 300 dpi maintains acceptable focus and clarity, while the 72 dpi image blurs.