The ultimate proof that you've met a celebrity is having the selfie to put up as evidence on social media.

But there are still fans who value an autograph - and are more than willing to pay for it.

London Film & Comic Con took place at the weekend with stars such as Michael J Fox, Freddie Kruger actor Robert Englund and Neve Campbell from Scream.

Fans can get a moment - and a signature - with their favourite star, so long as they have the cash to spend.

At the lower end of the price range, an autograph from a lesser-known star costs about £15, while someone like Neve Campbell asks £35 for a signature.

The "Diamond" packages - which include things such as an autograph signing, photo opportunities and seats at panel talks - are significantly more expensive. The Michael J Fox one cost £445 on top of the price of the entry ticket.

Find out what it's like to go to the London Film & Comic Con for the first time.

Fan - 'You've got to pay for what you love'

"We initially came just for Freddie Kruger (Robert Englund), but we've managed to get more autographs," say 23-year-old friends Heather Dempsey and Rebecca Barker, who are both from Liverpool.

"They can be really expensive. I didn't realise how expensive it was going to be," adds Heather, who was thinking of getting Neve Campbell's autograph until she saw the price.

"We paid £150 each to come and meet Robert Englund but I've always loved him so it's just what you've got to pay for what you love and what you're passionate about," explains Heather.

Fan - 'I'm in that fandom'

It cost Antonia Coates from south London about £45 to get Hayley Atwell's signature and she was happy to spend the money.

"She's in Agent Carter and I'm in that fandom. I love Hayley Atwell," says the 19-year-old, who also wants to get an autograph from Power Ranger Erin Cahill.

"I think it just shows that you are a true fan. This is someone that I'm very interested in and it's someone I'm willing to spend money on."

Star - 'I certainly owe the fans'

"I try to look at it from their [the fan's] point of view," says actor Sean Gunn. You may know him from Guardians of the Galaxy, or the TV show Gilmore Girls.

He's had plenty of people come up for his autograph (price - £15), while he has spent the day sat in a booth, in what he describes as a very "warm" convention centre.

"For each fan that comes up to me, that's what they're going to remember of me. So long as I look at everybody as individuals, it helps me not feel it's monotonous in any way," he explains, saying that he does feel he needs to make sure the fans get good value.

"I certainly owe them whatever honesty I can give them."

Fan - 'It's just nice to meet someone iconic'

"We got a Diamond Pass for Robert Englund - that was about £130 each. We got an autograph and a photo shoot so that was quite cool," says 20-year-old Ryan Hamilton, from Surrey.

"I've grown up watching the films and it's just nice to meet someone iconic who is your hero."

His friend Amy, who is 17 and from Somerset, says: "If you want to go into the movie business, meeting these people and asking them questions... It's definitely interesting from a job point of view."

They say it is "geeky" but it's a bit like going to a music festival "apart from you don't camp, so you don't get smelly".

Fan - 'Seeing all these great people'

Lydia Penn, who is originally from the US, now lives in Turkey and flew to London especially for the Film & Comic Con. She's spent "a lot".

"It's definitely worth it, spending your money and seeing all these great people," the 28-year-old says.

"I have a horror movie section in my living room. All my horror movie stuff goes on shelves."

Organiser - 'Biggest problem is stopping dealers'

According to the organisers, autographs cost about "half the price" in London compared to similar events in the US.

"They're actually cheaper here than on eBay and places like that," says Jason Joiner, director of Showmasters.

"The people who collect autographs do spend a lot of money, but they actually get really good value for money.

"The biggest problem we have is stopping traders and dealers coming in and trying to buy to resell."

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