Keep getting the itch for a longer reach for Airshow photos, I upgraded my lackluster AF Canon 70-300 (otherwise fantastic images below 200mm) to a second hand 70-300L which has blown me away AF wise and with the step up in image quality.

However, having not done a proper Airshow yet, I know I'm going to be short on focal length unless I crop in - bare in mind until recently I was using a 135L + 1.4x extender for my Airshow shots, which required large crops in on my 6D shots.

So here's the rub, will a 100-400L with a 1.4x give me enough reach for fuller frames at close proximity air shows, and importantly be fast enough or would something like the Tamron 150-600mm be a better bet... I realise that the 100-400II is rumoured to be coming this year, given the six of one and half a dozen of the other views on the 100-400 vs 150-600, I'm half expecting a wait till the 100-400II comes out - but in the meantime, I'd be interested in any views... And also on handling of the huge 150-600

So, crop into 100-400, or 100-400 + 1.4, or 150-600 - away ya go