[Brightcolours]

[quote name='Claus' timestamp='1347895423' post='20185']

You didn't get my point. Read careful.

[/quote]

The point is that you HAVE no point. It is a fallacy.



fallacy

noun ( pl. -cies)

a mistaken belief, esp. one based on unsound argument : the notion that the camera never lies is a fallacy.

• Logic a failure in reasoning that renders an argument invalid.

• faulty reasoning; misleading or unsound argument : the potential for fallacy which lies behind the notion of self-esteem.



If you want to go FF, you want to use FF. For that, you will need a FF capable lens.



With me so far?



Ok.



So, you need to buy a FF capable lens. Suppose you had a D7000 with a Nikkor 17-55mm f2.8 DX APS-C standard zoom. What could be a reason to want to go FF? DOF flexibility is a possibility.

Anyway. For you to have standard zoom FF capability you will need to actually buy a FF standard zoom. That is just how things are.

So. Now you have a D600, with for instance a 24-70mm f2.8 lens (FF standard zoom).

Does it make sense to use the 17-55mm and D600 as APS-C camera instead? No. The 17-55mm f2.8 on the D600 has lost its usefulness.



It is that simple. There is no extra value in that you have that 17-55 from before. None. One went to FF not to use it as a 10mp APS-C downgrade to the 16mp D7000.



The only advantage of APS-C usage over FF usage will be more tele reach when used with tele lenses (and one doesn't want to crop on the computer). But the tele lenses are FF anyway.