Rumours are continuing to circulate about the possibility of Canon announcing a mirrorless compact system camera in the next few months. With many people seeing it as an inevitably rather than a possibilty, the next question on everybody\'s lips is \"when?\" Canon is currently the only major player in the photography market not to have a compact system camera on the market. Its biggest rival, Nikon, finally entered the market towards the end of 2011, and has been enjoying fairly large success with its V1 and J1 models which feature a small sensor. Of course, it\'s not known what size sensor Canon will choose to use should it produce a mirrorless model, but a new patent discovered by a Japanese website appears to suggest an APS-C sized sensor could be in the frame. The patent shows a design for a new 18-45mm kit lens for a mirrorless camera. Premium compact Canon recently announced the Canon G1 X premium compact camera which features an almost APS-C sized sensor, but with a 4:3 ratio. Many are suggesting that this sensor is what will eventually make it into whatever mirrorless camera the company decides to announce. 2012 looks set to be a big year for Canon announcements, with rumours of an imminent Canon 5D Mark II upgrade in the shape of either a Canon 5D Mark III, a Canon 5D X, or possibly even a split in the line. It\'s also not known how compatible with existing Canon lenses a new product would likely be. Recently, the Pentax K-01 was launched which features a K-mount and large body in order to accept older lenses. The problem with creating full compatibility (without the need for an adapter) usually results in a larger camera body, which some would argue negates the point of a compact system camera in the first place. Stay tuned for more information on any Canon compact system camera as and when it emerges.