How do I choose scan resolution based on how I will use a photo?

Start with the intended use

For a standard print that will mainly be viewed on screens, shared with relatives, or included in a small digital album, 300 pixels per inch is commonly sufficient. Choose 600 pixels per inch when the original is small, when you want to crop a detail, or when a larger print may be useful later. Very small formats such as wallet prints, contact-sheet images, or tiny portraits may benefit from 1,200 pixels per inch if the scanner has genuine optical capability. Resolution cannot create detail that is not present in the original, so select a sensible setting rather than assuming that a larger number always improves the image.

Distinguish the master from sharing copies

Treat the first complete scan as a master file. Keep it at the chosen resolution, with the full image area and no permanent cropping. From that master, make smaller JPEG copies for email, messaging, web albums, or slideshows. This keeps sharing convenient while preserving a version that can support later printing or closer inspection. Name the smaller copy so it is clearly different, for example by adding “-share” or “-web,” rather than letting it overwrite the master.

Use scanner settings that matter

Look for optical resolution in the scanner documentation; interpolated or enhanced resolution makes a larger file by calculation and is less useful than real captured detail. Scan photographs in color, including black-and-white or sepia prints, because the paper tone and markings may matter. Use a file type suited to your plan: a high-quality JPEG is manageable for many household collections, while TIFF can be appropriate for larger master files when storage space and software support are available. Avoid repeatedly saving an edited JPEG over itself, since repeated compression can reduce quality.

Do a short trial before a whole box

Scan two or three representative prints at 300 and 600 pixels per inch, then compare them at normal screen size and at a close zoom. Note file sizes and how long each setting takes. If a 600-pixels-per-inch scan adds visible useful detail or gives room for a future crop, use it for that group. If not, use 300 and reserve higher settings for exceptions. Record the setting in a batch note so later scans remain consistent.

Sources

These official sources can help you check the next step for your equipment.

1. National Archives: Digitizing Family Archives — National Archives: Digitizing Family Archives
2. Library of Congress: Preserving Digital Images — Library of Congress: Preserving Digital Images

Before making disruptive changes

• Do not delete or replace a higher-quality master merely because a smaller sharing copy looks fine on a phone.
• Higher resolution increases scanning time, storage needs, and backup needs; check that your chosen storage plan can hold the masters.