best superzoom for Canon 40D

[DavidBailey]

Hi Camera guru's,
I have now decided on my first DSLR I am buying a 40D, as something I can "grow into" coming from a Lumix FZ20.
My First use is likely to be away in a very sandy, hot enviroment & I have decided to start with an ultra-zoom lenses only so i don't need to carry lots of lenses & i don't have to take the lens off in a hostile enviroment.
My logic is if i really get into the DSLR thing I can add other lenses later, but will always still find use for the ultra-zoom when travelling, so it will be a decent investment.

So two questions.
1/ Will the lenese below in combination with the 40D give me a good sized step up in image quality over my FZ20.

2/ Which of these lenses should I opt for, as I need a decent zoom for wildlife which is the main subject of my photos, whilst also wanting to take landscape photos!...

Tanrom 18-250mm (3.5-6.3)VC (stabilisation)
Tamron 28-300mm (3.5-6.3)VC (stabilisation)
Sigma 18-200mm (3.5-6.3) OS stabilised

or any other ideas?
Thanks for your help.

 

[mrgubby]

I've got the non-stable Tamron 28-300. It's an ideal walkabout / holiday lens and I've had some very good results with it

 

[DinoS]

depends if you need the wide angle, if so that it must be between the 10mm lens

 

[StewartR]

I have the Sigma 18-200 (non-stablilised, though I think there is also a stabilised version now) and it's a handy all-round lens. Not brilliant image quality, but great for the money. Thing is, I find myself using the wide end quite a lot. If you go for a 28-300, you'll find that 28mm isn't terribly wide on a crop-sensor camera like your 40D (and my 350D).

 

[8utters]

Also look at the Canon 70-200mm f/4 and f/2.8 L seris. There's 4 of them (two f/4, one with IS and one without, and two f/2.9, again, one with IS and one without).

The cheapest, the f/4 without image stabilisation is very cheap and a brilliant value for money lens, you can pick one up for about £300. Concidering it's L glass, it's a great deal.

The next lens I get for my 40D will be a 70-200, maybe with a 2x extender tube.