To resize old photographs, you can either photograph them with a good digital camera or scan them. If you’re resizing digital photos, use photo editing software such as Adobe Photoshop, Microsoft Paint or Gimp.
Use a digital camera to photograph paper photos for resizing. Depending on the size of the print, a 5-megapixel phone or tablet camera set to take pictures at the highest resolution should render good results. Open the new photo in photo editing software to adjust cropping and size. You can also use a flatbed scanner to make digital copies of photo prints. Scan prints at high resolution for good-quality copies, and then resize in photo editing software. To preserve original digital copies, remember to save the resized copies with different files names.
To resize a digital photo, open it in photo editing software to change its proportions. For instance, if you’re resizing a photo in Photoshop, select the Image menu and choose Image Size from the list of options. To maintain the photo’s original aspect ratio, click the Lock icon. Editing either the photo’s width or height changes the other dimension proportionally. To change a photo’s aspect ratio as well as its size, unclick the Lock icon. Make your changes, and then save.
Photographing or scanning old photo prints at high resolution ensures you have enough digital information to resize photos for good printed and onscreen images. To do the same with original digital photographs, set your digital camera to take the highest-quality images it can.