USGS Photographer at Work
![Image: USGS Photographer at Work](https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/s3fs-public/styles/full_width/public/MP013-300.jpg?itok=LGZjfAqT)
Detailed Description
Wright Todd applies light-sensitive color solution to a base sheet on a photo lab whirler. This method was used for generating color-composite proofing of map separate registration.
Sources/Usage
Public Domain.