Convert cals to psb

What is the difference between .cals and .psb?

Description: The CALS Raster Graphic File, having the extension .cals, is a type of image file format primarily used for the storage and exchange of digital images, especially in the context of technical and engineering documents. Developed in the mid-1980s by the United States Department of Defense, the CALS format was part of an initiative to standardize electronic document management and interchange, particularly for military and government applications.; Format used for saving large Photoshop documents over 30,000 by 30,000 pixels in size; supports images up to 300,000 by 300,000 pixels; to enable .psb support, check the "Enable Large Document Format" within the File Handling pane of the Photoshop Preferences window