The Project Apollo Image Gallery

apolloarchive.com

13 pointsdanhak3 comments

Can anyone explain the faint crosses on the photos? I've always been curious why they are there. See an example here: http://www.hq.nasa.gov/office/pao/History/alsj/a11/AS11-40-5...

It's called a reseau grid. The crosses are used as a reference points for measuring distances between objects in the image. They can also be used to correct distortions after development or scanning..

This page talks about it in detail. http://www.clavius.org/photoret.html

These images are fantastic. I just wish they had a better interface to flip through them.

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