I am trying to decide on standard zoom for a D700. The 24-70 f/2.8 appears to be the obvious choice for IQ, but the quality comes with a price. I am also looking at the Nikon 24-85 f/2.8-4. Does anyone have partical experience with both lenses that they can share. How much am I compromising IQ to save the $1K in price difference. I shout mainly landscape and flowers.
I was in a similar dilemma half a year ago. Since I needed a standard zoom lens urgenty I finaly decided to go for 24-85 f/2.8-4. After some studio testing I found it to be a very sharp lens. It does have some pincussion and barrel distortion on tele and wide end respectively, but when shooting landscapes and flowers you won't notice it.
How much do you compromise your IQ for the $1k price difference? For about $37.26 When shooting landscape and flowers you normally do that at apertures between 5.6 and 11, where the lens is at its sharpest performance. And at these apertures you will not notice the difference between this lens and much more expensive 24-70 f/2.8.
The lens also has a nice neutral color rendition and it is now my favorite lens on D700 for shooting landscapes and street photography. It is also much lighter compared to 24-70. Unless you are a pro or have an excess of funding, 24-85 will suit your needs perfectly.
Check some test pictures of flowers shot with D700 and 24-85 f/2.8-4 in my gallery here:
I have used both, and for your use case (landscapes and flowers), the 24-85 is the superior lens, without a doubt.
For landscapes: the 24-85 is free of field curvature, and when stopped down to f/8 or so (where landscapes are taken), the images are sharp and contrasty across the frame. The 24-70 on the other hand has strong field curvature, even at f/8, which can result in portions of the frame being out of focus.
For flowers and other closeups, the 24-85 is superior too, as it has a macro mode and allows higher reproduction ratios than the 24-70.
In addition to these advantages, the 24-85 is also lighter and less expensive and has 15mm more range at the long end.
So what's all the rave about the 24-70 then? For portraits, events and PJ use, it is much better than the 24-85, faster to begin with, and even at comparable apertures like f/4 at the long end, it is sharper in the corners.
I used a 24-85 from a friend of mine just to take a few shots and i have the 24-70. Both are really good for landscapes, but 24-70 has given me so many great shots that it would be unfair not to mention that works excellent on portrait shots like your flowers.