Hello adelie, and welcome to the Camera Labs forum!
These are exciting times to plan for buying a new camera
Here's my opinion in your case:
- Wait for the successor of the Nikon D200
(no, just kidding
- Buying gear with your heart? No, let your head guide you!
- You have a good investment in Canon glass? Go Canon!
- Is there a visible IQ-difference between four/thirds vs FF? You bet!
- Is the risk of blown highlights with landscape photography higher than with wildlife? Yes, unless you shoot birds against the sky!
- Is a 10mm on a croped sensor (equiv. 16mm on film-SLR) wide enough for your landscape ambitions? I guess so. But is certainly cannot beat a 12mm on a FF-body!
- Do you fear that the 5D will let you down on one aspect ore the other? Well, I don't know!
So you're left with three options:
- Buy the 40D, get a decent ultra-wide and be happy now
- Buy a 5D, get the Sigma 12-24 (it's FF) and be very happy
- Wait for the 5D successor, get the Sigma 12-24 afterwards, and be considered a "wise man". Whether you are happy to wait for so long, I don't know
I didn't mention the option for people with v.d.w. (very deep wallets): Wait for the already announced 1Ds mark III
In the end it all depends on how dissatisfied you are with your 20D.
Those, who can wait will be rewarded with better, cheaper, more mature gear
Hope that helps...
Thomas (beware: Nikon-fanboy and moderator!) My Lens Reviews
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