There are many Postcards that reproduce photos by various printing methods that are NOT "real photos"..same methods used when reproducing photos in magazines and newspapers.
I'll try to list here some common things that affect a postcards price.
Age: The age of a postcard can sometimes add to its monetary value.
These were illustrations on government-printed postal cards and on privately printed souvenir cards. Congress on May 19, 1898 granted private printers permission to print and sell cards that bore the inscription Private Mailing Card. Still, no message was permitted on the address side. postal regulations on December 24, 1901 stipulated that the words Post Card should be printed at the top of the address side of privately printed cards.
The government postal cards included a printed 1-cent stamp; the privately printed souvenir cards required a 2-cent adhesive postage stamp to be attached. The term Post Card was not widely used until the early 1900s (it was later contracted to "postcard" as a word-counting cost-saving measure). Government-issued cards were to be designated as Postal Cards (Staff, p. Writing was still not permitted on the address side.
They started printing view-cards of Boston and holiday cards in 1898.
This railroad that primarily transported coal and lumber had a history of slow expansion.
Cards can range from a few cents apiece to the hundreds and sometimes even thousands of dollars each!
Finding the true value of a card can be hard, with so many factors affecting its price.
One of the most enjoyable aspects of collecting postcards is the ease with which you can share your collection with other enthusiasts online.
Some of the postcard collections sites listed below are personal collections (and not for sale), while others offer to buy, sell or trade the Mississippi Department of Archives and History.
The easiest way to distinguish a real photo postcard is to look at it under a magnifying glass; it will show smooth transitions from one tone to another. (Britain had already pioneered this in 1902.) The address was to be written on the right side; the left side was for writing messages.