new guy, got the gear, no idea!

[unzy]

Hello people! I own a canon eos 400d and an ef 100-400mm lens which says I can pan a moving object and take pics of objects travelling at speed, I seem to be having some problems with moving objects blurring and cant figure out how to pan a moving object, please help.

[rojash]

See here:

http://lifehacker.com/software/photography/how -to-photograph-moving-objects-199194.php

[Clanad]

The tone of your query seems to indicate that your camera/lens may be new to you or you may even be a novice. Your camera/lens combination is certainly a top end pair, usually seen in the hands of advanced photographers. The long focal length of the rather massive EF 100-400mm lens can lend itself to some blurring if not handled properly. Just like all makes of such lenses, I might add. As you probably know, Canon has elected to place it Image Stabilization (IS) system within the lens rather than the camera body. Doing so, especially in long focal length lensesmeans the adjustments that are manually manipulated, like aperature and/or focusing can be sensitive. Here's a brief, informative review of your lens:
"The push/pull zoom mechanism is possibly the most noticeable physical feature of this lens. While it works smoothly, it took me some time to get used to it. There is a ring on the back of the manual focus ring that adjusts the tension on the zoom part of the lens. That is a nice feature, but I find myself constantly adjusting the tension to get it just right for the moment. The ring also gets in the way of the manual focus ring - when making a manual focus adjustment, I often inadvertently change the zoom friction ring as well. Set the zoom friction too light and the lens extends by itself when pointed downward - fast and hard if set really loose. Set the friction too tight and zooming becomes difficult. So, it works as it is supposed to. Some prefer the push/pull design."
Additionally, it's recommended by Canon that when the camera is tripod mounted the IS system should be turned off...
You may wish to invest in a smaller lens (17-55mm) for those "snapshot" type photos, saving your large lens for it's designed purpose. Good luck with your great camera!