I actually was back pretty far, like I said I cropped all of those shots, here is a shot before post processing just to show you what I mean, these were with my 18-55 on and fully zoomed in :
You think I need to back up farther than this? btw is the blur from being slightly out of focus or is it from the aperture depth? It it a bad idea to allow my camera to auto focus for me? This gecko was very well behaved and sat almost perfectly still for me, but the majority of the geckos im going to have a heck of a time getting them to sit still long enough to focus the lens manually