Avoiding Loss of Quality
If the original image is a JPG or other “lossy” format, before editing the photo first save it to a “lossless” format like RAW, PNG or Paintshop Pro’s PSPimage format. That way you can edit the image and re-save it with no loss of quality.
Every time you save a “lossy” format like a JPG image, you lose a certain amount of digital information, making the image less clear. You don’t lose any information with a “lossless” format like PNG no matter how many times you save the image.
When you are done editing, you can re-save the image to JPG or another lossy format if needed – for most uses JPG gives you the clearest image at the smallest file size – but hang onto that lossless version as well, in case you need to play with the image again!
Editing photos for print use
Confused over what size an image needs to be for print use? Join the club!
The short answer is this: take the width of the digital photo in pixels and divide by 300: that’s how wide (in inches) the printed image will be if printed at 300dpi (dots per inch). Do the same with the height.
For instance, an image that is 1800 x 1500px will print at 6 x 5” at 300 dpi.
What about the image’s resolution – the ppi (pixels per inch)? It’s very confusing (especially because some graphics programs call the digital image resolution “dpi”, which it is NOT), but in essence, the digital resolution refers only to how an image is displayed on a computer screen, and is irrelevant for print use. See my DPI vs. PPI page for a more detailed discussion.
Editing Film Photos
So what can be done with film (non-digital) photos?
Once a film photo has been scanned into the computer, a graphic editing program such as Corel Paintshop Pro can be used to clarify and enlarge it. Of course some things, such as excessive spotting or silvering of dark areas of background, can’t be completely fixed, but even they can be improved.
If the photo is scanned into the computer at a high resolution (such as 600ppi), the resulting digital image can actually be printed out larger than the original, which can be a great help with very small photographs.
Besides removing faults like spots, stains and tears, digital editing can be used to straighten an image, correct colour problems, and crop out unwanted features.
Film Photo Notes
When scanning a film photo into the computer, use the highest resolution you can – 600dpi is a good figure to use.
Not every film photo can be corrected, nor can all photos be made suitable for all uses. For instance, a very small film photo can’t be blown up beyond a certain point. Almost any photo can be made more usable, however, by digital image editing.
A scanned-in film photo will tend to have a visible texture, which is difficult to edit out. When really crisp images are required, a digital photo will usually be clearer than a film photo.
Film photos tend to deteriorate over time, and are subject to getting torn, bent, and stained. Once they are scanned in, digital image editing can be used to create clearer, better pictures. The edited images will also preserve your photos in a useable format.
You can do some things to help keep your print photos from deteriorating, of course. To find out how to preserve film photographs, read Properly Store Old Photographs.
If you are using images for anything, you need to be aware of – and in compliance with – copyright.
Quick Copyright guide:
If you created the image yourself (and did not copy it from a copyrighted source), you own the copyright.
If the image is in the public domain, it’s not under copyright and anyone can use it.
If the image creator has made the image available under a Creative Commons license, you can use the image under the specific terms of the license (the terms vary, so be sure to check them first).
You can PROBABLY use your own family photos – at least old ones – but this is an iffy area (for instance, privacy comes into consideration – you may need to get written permission from the person in the photograph before you can use it).
ANY OTHER IMAGES ARE PROBABLY COPYRIGHTED – and if an image is copyrighted, you CANNOT use it legally unless you negotiate (and probably pay for) the right to copy it (copy-right, get it?) with the copyright owner.
You’ll find detailed information on copyright and Creative Commons licenses on the Copyright page.