A lens conundrum *updated*

[magicaxeman]

You have two lenses of differing focal lengths, one is sharp as a tack, the other slightly soft at the end of its zoom range.
For simplicity I will use two I own as an example.

Canon 85mm F1.8, sharp as a tack
Tamron 55-200mm, slightly soft at 200mm

You take a shot with the Tamron @200mm, then the same shot with the 85mm.
After processing the raw, you crop the shot from the 85mm to match the view with the 200mm.

Which is the better image?

*update*
Well here's the shots, nothing fancy, just a pitcher plant in my rather grubby window, terrible light as well so had to tripod mount.

All have just had the raw processed using exactly the same default settings in ACR, then resized in photoshop.
I've just added thumbnails so click them for full size.

200mm @F8


85mm @F5.6


And heres the 85mm @ F8

 

[pete.rush]

85mm, but depends how you setup the shot, using the same settings for both

 

[Alison]

Both at f1.8?

If so, I'd guess the 85mm

 

[Strangways]

The 55-200mm wont be at f1.8, but a lot will depend on megapixels of the camera as to whether the crop will be acceptable.

My guess would be the Tamron at f8.

 

[magicaxeman]

Yes the shot would be the tamron @ F8, the 85mm @ F5.6

If we get some good light here tomorrow I will try it out and post the results.

 

[-halli-]

Could this be the "learn with MD" for this week? Will be interesting to see the results.

 

[magicaxeman]

Well the 85mm cropped seem's to yield the sharpest image, but the zoom 200mm throws the background out of focus better even at F8.

So to me it seems a shorter focal length,sharp lens works out better than a slightly soft longer focal length, even if it means a 50-63% crop of the original image.