Every two years the major camera manufacturers all gather at a huge convention centre in Cologne, Germany, to show off their latest camera gear. The 2012 show ought to be a biggie, particularly after  natural disasters in 2011 put the brakes on production of many major models.

As well as a number of already announced products that will be using Photokina 2012 as the platform to be shown off, there are plenty of rumours circulating about apparent forthcoming models. Here's our lowdown of what to expect from the majors at Photokina 2012:

After a quiet launch for the Nikon 1 J2, Nikon lifted the curtain on its big reveal: the Nikon D600.

We've already had a hands-on play with this sub-£2,000 full-frame camera and it looks like its trimmed price will be the perfect formula for those wanting to get the benefit of a 35mm sensor size.

The biggest camera brand in the world, and one that surely has to bring an answer to Nikon's D600. Rumour has it that Photokina 2012 will be the launchpad for the EOS 6D: Canon's affordable full-frame model. Expected to use a brand new 20-megapixel full-frame sensor, the weather-sealed EOS 6D is said to be far smaller than other full-frame models. If it's true then we'll be very excited to get our hands on this one.

But it's not just a DSLR that's expected. A PowerShot and IXUS range refresh is likely too, headed up by the PowerShot G15. Despite the launch of the Canon G1 X, it seems that the brand isn't finished with its smaller-sensor range quite yet. We hope to see a shrunken-down model that ticks all the high-end boxes.

Pocket-lint has already been privy to extensive hands-on sessions with Sony's major cameras - the Alpha A99, NEX-6 and Cyber-shot RX1.

We've already gone hands-on with the Sony Cyber-shot RX1 - the world's first full-frame, fixed lens compact camera - but hope to have a proper play with it at Photokina, this time with a battery included!

Pentax continues its under-the-radar announcements, and there's no press conference due at Photokina, but that's not to say there aren't exciting products.

We already know about the follow up to the K-5 DSLR - the aptly named K-5 II - and its low-pass-filter-free cousin, the K-5 IIs. We'll be going hands-on with the latest models to see what's new.

After a tepid reception to the original Pentax Q, Photokina 2012 will also be the place where the Pentax Q10 gets shown off. Though we're sure it'll be a fun little camera, we have doubts that the "Queen" system will ever truly take off.

It's been a busy year for Panasonic: The Lumix G5 compact system camera, LX7 high-end compact and FZ200 f/2.8 superzoom covered pretty much every angle. So what's left?

It's been a long time since the Lumix GH-series got an update, so this is a dead cert from what we've already seen teased by Panasonic. Not only that, but videographer Philip Bloom has also teased a video piece called "Genesis" shot using what he describes as a "pre-production new "G" camera from Panasonic". Looks like the company is happy to hype up the obvious rather than putting a firm lid on this one then.

Bloom continues, "More on Monday [17th September 2012]," a date that ties in perfectly with the event. We've already written extensively about the GH3 - which is touted to be the best video-capable stills camera out there - and will be at Panasonic's Photokina press conference to confirm all the official details.

The most concrete info we have of a new Pen camera has been revealed on a Tumblr account that shows a street shot with the camera in question "scratched out". At least we don't think it's an Art Filter gone wrong.

The unnamed camera shows a protruding lens, so we think it's about time that either the E-PL3 or E-PM1 got an updated.

As well as the X-E1 compact system camera, there's still the unsolved mystery of the rumoured - but fully specified and pictured - "X-F1" high-end compact camera.

As we said in our initial rumour report, this small-bodied model looks as though it'll have the same 2/3-inch sensor as the X10 compact, but with less of the control and bulk. Looks like it'll be a decent high-end compact if it's true.

It's been rather quiet on the Samsung front. The NX1000, NX210 and NX20 have all made their way on to shop shelves this very year, so it seems too early to update the NX range.

Sounds as though Photokina will be the place to show off the latest Android 4.1-enabled Galaxy camera then.