This is gonna upset some of you.....

For web use a D800 wouldn't be any better than a D300 unless you get way up there in ISO. But for large prints the D800 would be way better. Only other reason for upgrading camera are better focus system or better video again for web use.

So sure your correct. If all you do is web use I would spend my money on lenses to get what you need.

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http://www.pbase.com/dc9mm