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Star Wars actor Mark Hamill shows fans how to spot fake autographs

Collectors beware. Some dealers are channeling the dark side by selling fraudulently signed celeb photos. Hamill gives a Yoda-like lesson in telling the difference between fakes and the real deal.

"REAL!" Mark Hamill tweeted. "That's my old "M", which I changed over the years."

Mark Hamill/Twitter

Star Wars fans love to collect toys, posters, art, statues, Lego, home decor, beds, high-end costumes and even cell phone chargers -- if they have anything to do with their favorite characters from a galaxy far, far away.

So when Star Wars actor Mark Hamill started to see more and more photos of himself as Luke Skywalker signed with a fake signature, he felt compelled to speak out on Twitter.

"Hope everyone can learn my real signature to help prevent fraudulent dealers!," Hamill tweeted on Sunday. "I owe it to all true fans to protect them from being victimized by dishonest dealers!"

The actor posted several examples of what his autograph looks like faked and in reality so fans can hopefully tell the difference and save money in the process.

In some cases, fans wondered if signatures were real mainly because Hamill had so much fun signing them with jokes -- sometimes using adult humor -- about C-3PO, his "dad" Darth Vader and Tusken Raiders. "Man wanted extreme irreverence," Hamill tweeted when asked about the amusing signatures. "Give the people what they want. Never thought they'd go public."

Be sure to follow Hamill on Twitter to see multiple examples of what his real signature looks like so you too won't be fooled into buying an imposter.