This is something I learned from the School of Hard Knocks in my early days of scanning.
If you allow your photo scanner to do what it wants – its default settings – it will produce a digital image file that is the exact size of the original photo print. If later you want to blow up the image in an print enlargement, or place it as a full page in a photo book, it won’t work. The enlarged image will be seriously degraded.
We want to control the scanning software and adjust the size of the digital image to be created and saved.
For most scanning software this is accomplished by adjusting the scan RESOLUTION setting. Other scanning software may do this by adjusting Percentage or Image Size.
If found that other scanning videos and tutorials do not stress this point. It can be a huge issue.
When all else fails, Scan Big!