I am using Photoshop CS4 and I found a way using image processor to change the quality of the JPEGs. However, I want to change my pictures resolution from 300 DPI to 75 DPI for web posting. Can Photoshop CS4 do that, if so how? Or any other free program that might be able to do it? Thank you for your answers!How to change a batch of pictures%26039; DPI automatically?
dpi is the print quality, ppi is the image file resolution quality for viewing on screen, if you have images at 300 resolution those can still be viewed online, but file size would be larger for same size image in inches, so you can resize the resolution from 300 to 72 or 96 ppi, and save that set of steps as action script, then apply to other set of images, there is also the quality compression you can change when saving as new file in photoshop, test those options for file sizes as well,
Photoshop CS4 ~ Recording actions
http://help.adobe.com/en_US/Photoshop/11
http://digital-photography-school.com/ho
if you have to change dpi out side of photoshop for printing, may require other tools for batch file processing,
..
