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J.davis
22-11-2014, 10:51pm
I have a d7000 and am thinking of going full frame to a D750.
Question for you,
will the D750 render a better quality pic for a given set of values than that of the D7000.
ie:
same settings, same lens, same subject and distance at the same time of day (virtually same photo)
If the D750 pic is cropped to D7000 size, will the pic qualities be better for the D750?
Waiting with baited breath :D

arthurking83
23-11-2014, 9:34am
In Dx crop mode, the D750 will have 'less pixels' than a non cropped D7000 image.

Whether this is better of worse in terms of image qualities is up to the shooter.

Considering the newer technology of the D750's sensor and inherent processing ability, it's not hard to hypothesise that the D750 image should at least produce less noisy images at elevated ISO values.

I'm just now comparing some sample images(ISO's 6400, 12500 etc) and the D750 is miles ahead in terms of chroma noise rendered in the images(as expected above).

What I like to do when comparing is to view them in Nikon's software to see how much noise reduction Nikon applies to their raw images, even tho NR is turned off in camera!
It's well known that at elevated ISOs even with NR turned off, some NR is still being applied.
With Some of Nikon's software, you can not only see this application of NR, but also turn it off(to a degree).

With NR in camera set to off:
D7000 at ISO6400, the NR settings via the software are: NR set to Fastest, NR levels are Intensity 7, Sharpness 5.

D750 at ISO6400, the NR settings via the software are: NR set to Fastest, NR levels are Intensity 0, Sharpness 5.
(it's got me stumped why they set NR to on, and not really used it, other than for a bit of sharpness .. which is not only an extremely low setting as far as sharpness is concerned, but also makes no difference to the image in any meaningful manner!)

The colour noise in the D7000 file at these settings is about what you see from the D750 at ISO25600 at the same settings(ie, NR set to off and subsequently cancelled again via Nikon's software)

Also not too tho:
Another thing I like to do, is to compare images with various sets of NR(of an easy to apply routine) .. so I set NR(in software) to various levels and points.

The D750 image accepts a lot more noise reduction application than the D7000 image can. Conversely too tho, less NR application is required for D750 files.

As an example of what this can mean, and how it can be used to advantage.
In the comparison between the D750 @ ISO25600 and the D7000@ISO6400, using CNX-D(which is a major PITA!!) I can set NR to best quality for both of those images.

But for the sliders, I can set luminance noise to less than 10 for the D750 image and chroma noise to about 20-ish and to achieve similar chroma noise reduction on the D7000 image @ ISO6400, it needs a bit more from each slider, which then results in reduced detail rendering .. then needing more sharpening .. which then products more artifacts, which then requires a bit more luminance NR .. thus creating a viscous cycle of IQ destruction!

So in effect, while the raw image may display a 2stop advantage for the D750, with a bit of common sense practical application the advantage for the final output may be more.

Note that in all the above testing/sampling/fiddling, I'm looking at the images zoomed in to 100% pixel view.
I assume that when using DX crop mode on the D750, you would be seeing an approximately 10-12Mp APS-C file compared to the 15Mp D7000 file. While it's not a massive difference in pixel count, there may be a slightly lesser difference than those I've described between the 2 cameras sensors(ie. maybe not a full 2Ev advantage to the D750 .. more like 1.5Ev noise advantage).

Final comment: will you see an advantage in replacing the D7000 with a D750. I think you will.

ameerat42
23-11-2014, 10:17am
Hmm! The "quality" questions I can only guess at, given some facts gleaned from the respective specs of the 2 cameras.
In summary:
1) For the price difference you would expect "better" Q from the D750 than from the D7000.
2) The pixel size is much larger in the D750 than in the D7000. (~1.48 wider, so just over 2x the area.)
3) If you cropped the image of a D750 to the size of one from the D7000, you'd end up with an image of about 11 MPx.

Even after that you'd have to do a side-by-side test for any useful comparison.
I could only guess that for all conditions being equal, and going only on the signal/noise ratio as indicated by AK, the D750 would have
to have better Q than the D7000.

You might approach equivalence by setting the ISO of the D7000 lower than that of the D750.
Am(omly guessing:o).