QPix v2.2

Advanced topics


Working with high-resolution images

Image files come in a variety of resolutions that may or may not match the resolution of your monitor. Macintosh computers have a monitor resolution of 72 dpi, while Windows usually have a resolution of 75 dpi.

QPix v2 maintains the original image resolution throughout its operations on images, including transfers from or into the Clipboard.

When QPix displays high-resolution images there are mutually exclusive two options:

Preserving natural size

Doing this will cause many of the pixels contained in the original image file not to display. This happens because the screen cannot show all of them and preserve the dimensions at the same time. In other words, the pixel size of the screen is too big compared to the pixel size of high-resolution images.

For example, the pixel size of an image scanned at 300 dpi is 1/300 of an inch, which makes it 4 times finer (smaller) than what the Macintosh screen can display (1/72 of an inch). In this case one screen pixel must replace 4 x 4 = 16 original pixels, if we are to preserve natural image size.

Displaying all pixels

The other option is to display all pixels contained in the image, but the size will not be the natural one any longer. This is how Photoshop displays higher-than-screen resolution images; if you open a 300 dpi image of a stamp with Photoshop, you will certainly not get a stamp-sized image. Because Photoshop is a pixel editing environment, the need to display all pixels is predominant. That’s why the image size will be 4 times bigger across each dimension than the natural size of the stamp.

QPix is not a pixel editing software, so the default is to preserve the natural size of the image. To display all pixels, uncheck the Display natural size checkbox in the Advanced Properties Dialog.