The Washington Post Magazine invites area amateur photographers of all ages to compete in the magazine's fifth annual photography contest. The theme of this year's competition is "Working." Entries must reflect this theme but will not be interpreted rigidly so long as the subject matter, in the opinion of the judges, is clearly related to the theme. For example, a bus driver who turns around one day to photograph his customers would fit into this theme, as would a photograph of the bus driver by a passenger. A photograph by a crane operator who gives us a view of his work place would be acceptable. A photograph of a beaver diligently building a dam also would be acceptable. Categories

Entries will be accepted in four categories: color photographs, black-and-white photographs, "instant" photographs, and photographs taken by persons under 16 years of age. Deadline

All entries must be received by 5 p.m. Friday, July 31, 1981. Prizes

A first-prize award of $100 will be presented to winners in each category. There will also be two $50 second prizes awarded in each category. Other entries of particular distinction will be recognized by certificates of honorable mention. Judges

Judges for the contest will be a panel of experts in the visual arts drawn from inside and outside the staff of The Washington Post. Rules

So that your entries will receive proper handling and judging, please read and carefully follow these rules: 1. Amateur photographers of any age may compete in the color, black-and-white, and instant categories. The youth category is open only to photographers under 16 years of age on July 31, 1981. An amateur will be considered to be someone who has not sold one or more photographs for a total of more than $25 from July 31, 1980, to July 31, 1981. 2. Contestants may submit up to three entries in each category for which they are eligible. Photographs must have been taken between July 31, 1980, and July 31, 1981. 3. Entries may be mailed to The Washington Post Magazine Photography Contest, The Washington Post, Washington, D.C. 20071, or delivered to the security guard's desk in the lobby of the Washington Post, 1150 15th St. NW, in an envelope marked "Washington Post Magazine Photography Contest." 4. Black-and-white entries must be glossy or matte-finished prints no smaller than 5" x 7" and no larger than 11" by 14" including mounting, if any. No negatives will be considered. 5. Color entries may be 35mm transparencies or glossy or matte-finished prints no smaller than 2 1/4" x 2 1/4" and no larger than 11" x 14" including mounting board, if any. 6. Instant photography entries (from cameras such as Kodak's Colorburst or Polaroid's SX-70) must be in color and should not be "manipulated" in any way. Entries should be submitted exactly as they are ejected from the camera. Enlarged or reduced instant photos will not be accepted for this category but may be submitted in the other categories. 7. Each individual print or slide must be marked on the back with the contestant's name, address and category. 8. Contestants who want their entries returned must include a stamped self-addressed envelope of sufficient size with the submission. The Washington Post cannot accept responsibility for loss or damage of entries, although all reasonable care will be taken with them. Contestants should submit padded envelopes or packing material to protect their entries when returned. Entries will be returned only by mail and only if a self-addressed stamped envelope is enclosed with the entry. Photos not clearly marked with the contestant's name and address will not be considered by judges. 9. To be considered, entries must be received no later than 5 p.m. July 31, 1981. Winners will be announced and most published in the Oct. 4, 1981, issue of The Magazine. 10.Employees of The Washington Post, its subsidiaries and members of their families are ineligible to compete.