Can someone help? How bad is using a 2x converter?

[LoneSierra]

That sounds great. Yeah, I know that dropping the two f stops will definately not work well for football under the lights, but that's the beauty of this setup. It wouldn't work with the straight 400 either, because that's a 5.6 as well. I don't have the money for a 2.8 400mm at all. I need to start making money on my pics first. haha As I'm just getting started, I want to buy lenses that are worth it, but that I don't have to sell internal organs for.


So in that case, of the football game under the lights, at least I could get rid of the extender, and at least get the speed of that 2.8 lens, that way I could at least the shots clear. The 50D has 15 megapixlels to play with, so if I put a good lens like that on, at least I could crop down pretty well.


I'd love to see what the pics look like. I was worried about chromatic abberation, as that's one thing I heard about using extenders, but we're talking about a really good sharp lens, not just a cheap lens, so I feel it's still going to provide all but the best shots with the extender.


Thanks for your reply. Now that I have that info, I think you helped me dedcide on what to do. Justhaving someone who actually uses that setup withgood results is really what I wanted to hear.


I look forward to your email! (Will private message the address.)


Also, I appreciate any other comments anyone else has to offer! Thanks everyone!

[Feanor]

I've had this exact same combo for a while, although I haven't really used it much in anger. In anything except for the brightest light the AF is awfully slow and often hunts. I'm not very impressed by my 400D's (Rebel in US terms?) AF in general but I have a 5DmkII on order so I'm hoping that will improve things somewhat.


It's just a stopgap measure for me though, albeit one for the forseable future. All the advice I've had is that it doesn't compare with the 400mm f5.6 for AF speed etc. But that doesn't have IS - my 70-200 f2.8 does. If I'm to spend £1k on another lens I want it to have IS - I find it really odd that the f5.6 varient isn't available with this, and wonder if Canon will release one at some point.


If I do find myself with money to burn - and if I either decide that IS isn't so important, or Canon release such a beauty at f5.6 - I will probably get one. But the 2x Extender still won't have been wasted - I can then use it for a lovely 800mm zoom, albeit with MF only. It might not be much use but it would be cool to have .