If you want two effects placed on one items, you're going to have to use two different sets of flags. Changing Image Size To begin this discussion, let me state that images on a computer are not like photographs. Computer images are made up of a lot of little colored dots. So, just remember that during this part of the Primer, numbers refer to pixels rather than inches, or centimeters, or whatever. When I say pixels, I'm talking little colored dots.
Every image is made up of pixels.
The more pixels per inch the image has the better, and more detailed, the image will appear. Of course, that also means the image will take up a whole lot more bytes on your hard drive. You're going to find that most images on the Web are 72 and 100 pixels per inch. Yes, there are other settings, but 72-100 is a good trade off between loss of detail and bytes required. OK, so every image is made of pixels.