Dennis, Can you enlighten us to the advantage of FX vs DX as you see it.
What sort of cropping can you achieve without loosing quality in the image ?
ISO 1000 doesn't give that much advantage over ISO 800 on my D300s.
Thanks Dave
Hi again Dave
In my own opinion the main disadvantage of the FX sensor in the D3 is the fact that my 600mm is 600mm. With the DX sensor it is effectively about 900mm, giving extra 'reach'. In bird photography 'reach' is important, as a 600mm will give you 20% more than a 500mm. Getting inside a bird's 'circle of fear' is an essential fieldcraft art and the more 'reach' a lens has the better.
The loss of the crop factor is more than made up for in the FX D3 in the superb high ISO performance. No noise artefacts at ISO 1600 at least and a superb 'bokeh'. This allows me to use higher shutter speeds for a given subject than my old D2xs which could only be used up to ISO 800 before exhibiting noise.
With my FX sensor on the D3, the apparent sharpness is hugely improved, the colour gamut seems wider and, as I specialise in flight shots, I can use a 600mm at 9 frames per second in RAW.
In Capure NX2 I can easily enlarge to 66%.
I do miss the 'extra' 300mm a DX sensor gives but the image quality is sooooo much better than my D2xs.
I sometimes add a 1.4x convertor but lose a stop in doing so but with no loss in quality.
I am still amazed at the quality Nikon seem to get out of their 12.3Mp sensors.
As an aside, the biggest improvement to image quality came from switching to a Gitzo 5540 tripod and Wimberley head. I oftens see folks hand-holding long lenses and feel they are not getting the best out of them even with VR or IS on.
Hope this helps a bit. There are many opinions out here on t'internet and there is always somenone out there who wishes to disagree. Do ask lots of questions, maybe someone will give you the exact answer you are looking for. The D300 produces superb results if you give it a chance and combined with a 600mm you will be able to get stunning results.