D7000 v D4 Image Quality

Hi
I currently own a D7000 and my main interest is in sports photography. I use it mainly with a Nikon 70-200 f2.8 and am very happy with results. A lot of the images I take do involve cropping.
Anyway, I was drooling over a D4 and trying trying to convince myself that I would get better image quality with the D4 when I had a few thoughts.
Leaving aside that that the D4 wins in loads of other departments but focusing specifically on image quality, am I right in my following assumption.
Both cameras are 16.2 MP with very similar sensor sizes. If I were to stand in the same place and photograph the same object with the my 7-200 lens would there be any better image quality with the D4?
I think the answer is no. In fact the D4 would not benefit from the 1.5x magnification I get with the D7000. So if I wanted to reproduce the same image proportions I would have to crop the D4 image and I am guessing loose image quality.
Am I right with this.

First off, the sensors are not similar in size. The D4 is a full frame camera and it's sensor is 2.5 times bigger than the sensor in the D7000. The IQ from a D4 is going to be better than an image from a D7000, there is no debate there. Other than that, I am not to sure what you are trying to get at. Why on earth would someone want to crop an image from a D4 to get it to the same size as a D7000? As far as I have been told, if you crop an image, you are not losing any IQ. Remember, when you have a DX sensor, nothing is really "cropped". The sensor just ignores information. Also, the focal length of a lens never changes, just the field of view.

The Nikon D7000 uses a DX sensor measuring approximately 23.6 x 15.8 mm while the Nikon D3 uses an FX sensor that measures approximately 36.0 x 23.9 mm so I'm going to have to say, no...

Your assumption is not correct.

Both cameras are 16.2 MP with very similar sensor sizes

Click to expand...

No they do not. The D7000 is DX and the D4 is FX. Those are not similar sensor sizes. In fact, a DX sensor is only about 43% the size of an FX sensor in area. Night and day. The D7000 is not even in the same league as the D4, nor is it intended to be.

Well there you go, you have your answer. You are just going to have to get the D4.

RON said:

Well there you go, you have your answer. You are just going to have to get the D4.

Click to expand...

And a Nikon 200-400mm F4 to go with it...Should be a great combo

Hi
Thanks all for your kind replies. I think I need to expand.
When I said the sensors are a similar size, the size I was referring to was not physical size but number of pixels.
The D7000 has 4928x3264 the D4 has 4928x3280 which means they both have the same number of light gathering sensors, its just that the D4's are bigger and further spaced, hence the brighter viewfinder.

"Why on earth would someone want to crop an image from a D4 to get it to the same size as a D7000?"

Let me expand. The scenario I was trying to portray was, say we are using the 70-200 at the full focal length of 200mm taking a photo of a racing car, stood behind a barrier, i.e. I cant physically get any closer and I want the car to fill the frame. With the D7000 and the 70-200 at 200mm focal length because of DX sensor this gives me an effective focal length of 300mm and a corresponding angle of view. Same position but using a D4 results in my 70-200 giving me a true 200mm focal length and a wider angle of view. I would then have space around the outside of the car. If I now want to fill the frame with the car (using a D4) I either have to buy a 300mm lens, move closer (which I cant), or crop the image.
I think the resulting image from the D4 would be somewhere in the region of 3252x2164. If both images were now say printed at 300dpi, I think I am right in assuming the D7000 would print larger or be better at the same print size?

This is what I am trying to understand.