The size of an image stored in a data set is different from when it is loaded in main storage. You can calculate the amount of main storage required after loading as follows:

• Load the image in the VIEW ENTRY PANEL from ISPF.
• Go to the last line.
• Multiply the last line number by 71 and divide it by 4096.
• Ignore the decimal places.
• The result is the number of pages needed for that image.