You can make a difference in the Apple Support Community!

When you sign up with your Apple Account, you can provide valuable feedback to other community members by upvoting helpful replies and User Tips.

Looks like no one’s replied in a while. To start the conversation again, simply ask a new question.

importance of photo resolution in using "Retouch" feature

I have old archival photos that need to be cleaned up with the "Retouch" feature of the Photos app. The ones I have are 600 dpi. Will that retouch feature work better if the images are rescanned at a greater dpi - let's say 1200 dpi? (I have used Retouch on these images at 600 dpi and the results are quite good, but if it is possible to make them even better I want to do that. If so the government archives, from where these images come, say they will rescan them at higher resolution.)


Thanks

John

iMac 21.5″, macOS 11.6

Posted on Nov 24, 2022 9:11 AM

Reply
Question marked as Top-ranking reply

Posted on Nov 24, 2022 9:32 AM

The best scanning resolution will depend on the resolution of the originals you are scanning.

Are the originals graphics with very thin lines? Or printed photos or films, where you can see the grain? If you are scanning line drawings, the scanning resolution should be good enough to sample the thin lines densely enough to separate all lines clearly. But for films and prints, you do not need to scan the grain in high detail.


I would scan the photos with the highest resolution that makes sense for each photo and is supported by the scanner. Retouching is easier at a high resolution, if the boundaries of the blemishes are clearly defined and not blurry.




3 replies
Question marked as Top-ranking reply

Nov 24, 2022 9:32 AM in response to campbellstreet

The best scanning resolution will depend on the resolution of the originals you are scanning.

Are the originals graphics with very thin lines? Or printed photos or films, where you can see the grain? If you are scanning line drawings, the scanning resolution should be good enough to sample the thin lines densely enough to separate all lines clearly. But for films and prints, you do not need to scan the grain in high detail.


I would scan the photos with the highest resolution that makes sense for each photo and is supported by the scanner. Retouching is easier at a high resolution, if the boundaries of the blemishes are clearly defined and not blurry.




Nov 24, 2022 9:54 AM in response to léonie

Hi.


Thanks for the reply.


The images I am working with are relatively small images taken c. 1870 held by a local archive. They are scanned at 600 dpi, which the archivist tells me is the archival standard. But as I say, he says they will scan the originals at a higher resolution if I need that. The main problems in each are fold marks. The images as pictures are not of as high a resolution as I'd like, but they will do (for inclusion in a documentary) if I can deal with the fold damage. Here attached is one of the two photos.


John

importance of photo resolution in using "Retouch" feature

Welcome to Apple Support Community
A forum where Apple customers help each other with their products. Get started with your Apple Account.