Postcard format

postcard format cameras Heag II Ser. II, Junior and Black Beauty

Some exposure formats are also known as postcard format. These are

Format	Aspect ratio	centimetres
10×15 cm	2:3	10×15
3¼×5½ inch	13:22	8¼×14

These exposure formats are all resembling the format of postcards or postal cards. These means of communication became popular since 1875 when the postal card was accepted as international standard for lower rate message sending on un-enveloped rectangular pieces of cardboard, postal cards mainly w/o picture as kind of prepaid letter, postcards with image side mainly needing a stamp. In the early 20th century the format was quite popular for photographs. Image prints could be made on cards with field for address and stamp on the back.

Links

• Postcard on Wikipedia