As technology advances and high-quality scanners become more affordable, folks often ask how they can scan photos on their own in a format suitable for our fine-art books. Although not easy, it is certainly possible to get a top-quality image from your flatbed scanner at home. Below is a quick guide for how to scan your own photos. Of course the easiest approach may be to skip this technical how-to and have someone who’s experienced with computers, scanners and image resolution do it for you.
There are several factors that affect the overall quality of a scanned image, including:
File type, or the format to save the file in.
Resolution, or how many pixels can be saved into a one-inch-square area.
Output ppi, or how many pixels per inch the image is scanned at (sometimes referred to as dpi, or dots per inch).
Scaling, or what percentage increase the final output size is versus to original photo’s physical size.
Compression, or how much file sized is saved by sacrificing image quality.
Scan type, or the setting that determines the type of photo you’re scanning (grayscale, color, etc.)
Crop, or where the edge of the image sits.
Histogram or curves adjustments, or how the scanner will map the tones in the photo to a digital image file.
Bit depth, or many shades of color can be contained in the image file.
If this list seems overwhelming, don’t fret! If you only get one thing right, be sure to set the resolution correctly (details below). All other factors are minor and can be less than perfect and you’ll still end up with a usable image.
Scanning with a Flatbed Scanner:
Because there are countless versions of scanning software, this guide cannot run through the process in step-by-step fashion. Instead, here are the areas to look for in your scanning software’s settings…
Clean up: This isn’t a software setting, but it’s always a good idea to be sure you photo is free of any surface dust and your scanner’s glass is as clean as possible.
Resolution: Set this to 600ppi (or 600dpi, depending on your software’s terminology).
Output size: This area should either ask you for a desired percentage to scale the image to, or desired width and height dimensions in inches. The goal is to have a final image file that is 3,600 pixels on the long edge. If we assume the resolution is locked at 600dpi as laid out in the step above, setting the output to 6 inches wide for a horizontal image, or 6 inches tall for a vertical image, will do the trick.
As a quick side note, lots of people get confused when talking about image resolution and pixels, but it’s really quite simple. The key is using pixels as your starting point, then figuring out the resolution of the final output from there. For our books, we print at either 300ppi or 400ppi. PPI stands for pixels per inch, so to figure out how big an image could run in one of our 300ppi books, we simply divide the number of pixels in the image, width or height, by 300. For example, an image that is 1,200 pixels wide could run as large as 4 inches in on of our 300ppi books (1,200 divided by 300 = 4). The goal for all scanned images is to have the flexibility to run them full page (or even larger) in the book. A full-page photo may end up about 12 inches wide, which is why the target number of pixels in your scanned image is 3,600 pixels (3,600 divided by 300ppi = 12 inches). If this is all too confusing to you, just set your scanner to 600dpi and hope for the best of the rest of the setting. Chances are, you’ll be pretty close!
Scan type: Set this to grayscale if you’re scanning an old black-and-white photo. If you’re scanning a photo with color, set this to RGB color. Some scanning software labels scan types with bit depth settings as well, such as 8bit, 16bit or 24bit. Any bit depth will work, but the higher the better in most cases.
Crop: It’s best to set the frame of the image (or crop) to just the actual photo itself, not its border or any other surrounding elements. This isn’t essential, but helps.
File type: The options are typically BMP, TIF, PSD and JPEG (or JPG). TIF and JPEG (or JPG) are the easiest formats to work with, so stick to either of one of those. TIF is a tad higher quality, but the file size a lot larger. JPEG (or JPG) is perfectly fine so long as whatever compression settings are turned way down (so, very little compression) or quality settings are turned way up (high quality).
Save to: When your software asks you where you’d like to save the image file, pick anywhere you’d like. Just make note of where you’re saving it so you can grab it and upload it later on.
Scanning with a Photo Scanning App on Mobile Device:
If you have a phone that does not have a high resolution camera, you can use a scanning application instead. These apps allow you to make a higher resolution digital copy than is possible with many cell phone’s built-in cameras.
How do they do this? While there are too many apps to speak comprehensively, the basic gist is this: Rather than taking a single photo, the app will take multiple photos of the different parts of the original, then “stitch” them together.
Once the scan is ready, you are able to save it to your device, or send it via email, Google Drive, etc. so that you have it saved online to share for the book.
Editors at Pediment have had success with the app PhotoScan*. This app has you take four photos of the original, one for each ¼ of the image. While this does mean that it takes longer than snapping a regular picture, the result is a photo with high enough resolution to be included for publication.
And that’s it! You should have a high-quality image file saved to your computer, ready to send to us for book publishing. We hope this helps, but be sure to contact us if you have any trouble.
*Pediment is not affiliated with PhotoScan. There are many photo scanning apps that are available for both iPhone and Android, find one that works for you