Results of Resampling Photoshop Elements 10 Images
In some cases, images are too large, and you need to reduce their resolution and physical size. In other cases, you might need a higher resolution to output your images at larger sizes. This method of sizing — changing the size, as well as the number of pixels — is called resampling an image. Specifically, reducing resolution is downsampling, and raising resolution is upsampling.
Use caution when you resample images; when you resample, you either toss away pixels or manufacture new pixels.
As a general rule, reducing resolution is okay, but increasing resolution isn’t. If you need a higher-resolution image and you can go back to the original source (such as rescanning the image or reshooting a picture), try (if you can) to create a new file that has the resolution you want, instead of resampling in Elements. In some cases, upsampled images can be severely degraded.
If you take a picture with a digital camera and want to add the picture to a web page, the image needs to be sampled at 72 ppi. In most cases, you visit the Image Size dialog box, select the Resample Image check box, add a width or height value, and type 72 in the Resolution text box. What you end up with is an image that looks great on your web page.
Here you can see an image that was downsampled in Elements from over 14 inches horizontal width.
If you start with an image that was originally sampled for a web page and you want to print a large poster, you can forget about using Elements or any other image editor. Upsampling low-resolution images often turns them to mush, as you can see here.
You might wonder whether upsampling can be used for any purpose. In some cases, yes, you can upsample with some satisfactory results. You can experience better results with higher resolutions of 300 ppi and more if the resample size isn’t extraordinary. If all else fails, try applying a filter to a grainy, upsampled image to mask the problem.