Honestly, Canon users, and I am one of them, if Nikon made an D800 version with EF mount, and you are in the market to upgrade your camera, which one will you buy, a 5dIII for $3500, or an EF mount D800 for $3000?
the problem is many of us stacked with Canon glasses and try very hard to prove that 5DIII is as good as D800, but it is not.
Then just put the glass up on eBay. I've bought and sold glass on eBay for years. Sometimes even made a profit (bought a new lens on Adorama and sold it after two years on eBay with a $200 profit!). Glass usually hold it value well over the years but bodies deprecate a lot.
So the argument that you have a lot of glass and that's holding you back rings a bit hollow to me.
Well here's the thing. When you sell your glass, you have to replace it. And when you replace it, is it an upgrade or a downgrade? Let's look at my lenses:
17-40 f/4L - switching to Nikon would be an upgrade
24-105 f/4L - switching to Nikon would be a downgrade
70-200 f/2.8L IS USM II - switching to Nikon would be a downgrade
24 f/3.5 TS-E - it's the version I, so switching would be an upgrade. But buying the version II Canon would be an upgrade as well. I'd call this a wash.
24 f/1.4L II -- switching to Nikon would be a downgrade.
50mm f/1.4 -- Depends on what Nikkor I bought. Possible upgrade or sidegrade.
85 f/1.8 - switching to Nikon would be a sidegrade
The reality is I wouldn't be able to afford to replace everything. And my favorite lenses are lenses where the Nikkor equivalent just isn't as good. Too much hassle for a camera that's a lot more similar to the 5D III than different.
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