My methodology to assess the D3x’s noise signature was pretty simple. First, I made a variety of similar images using a tripod, and a new Nikon 24-70 mm f2.8 lens set at 70mm. The idea was to vary the ISO on each camera, shoot on aperture priority (f5.6, just to make it interesting) letting the shutter speed adjust as required by the change in ISO, but to have everything else stay the same. The original reference image was of a backyard scene. The red rectangle shows the crop used for noise analysis in all the subsequent images.
Basic Methodology - D3 vs. D3x Direct Noise Comparison
For the initial direct comparison test, I turned off just about everything I could in both the D3 and D3x. In short, there was NO in-camera noise reduction or sharpening applied. As it turns out, this is NOT the way I think we'll be shooting the D3x (are you still interested in this little test?) but it's the way many of us have shot everything from the D100 through the D2x to the D3. At least underwater.
I made similar images with each camera at ISO 100, 200, 400, 640, 800, 1000, 1250 and 1600. I'm sure some terrestrial photographers are checking out ISO 3200+ even as we speak, but for underwater photography, I personally try to keep the D3 at 640 and below if possible. I'll ramp up to 800 if required without too much angst, and I never shoot above 1250 even under dire circumstances (like Alcyone at 7:30 am in the rain). It's all about the noise, even with the magnificent D3. So, my personal shooting style dictated my ISO test parameters.
The biggest issue I faced this morning was how to process the RAW images. As we all know, Nikon doesn't even give you a raw converter in exchange for your $8000 (I plan to throw red paint on the Chairman of Nikon and shout "Shame! Shame!" if I ever meet him). Besides, I hate Capture NX2. However, the folks at Adobe are still struggling to keep ACR up to date with the raw conversion coding for every bloody new point-and-shoot that's come out in the last quarter, Phase I is behind as well, forget about Aperture, and even Bibble isn't ready for the D3x. Which led me to discover a rather marvelous little raw converter called ... you guessed it ... "Raw Converter", by Iridient Digital, Inc. For $125 I downloaded a license that is good for 15 months, and opens D3x raw files just fine. If fact, it may be hard to get me back to ACR. This is a very sweet little raw converter. But that's another story .... although I would suggest you check it out when you can:
In any event, to keep everything as consistent as possible, I turned off everything I could in Raw Converter, INCLUDING SHARPENING AND NOISE REDUCTION. I also used all the default settings. NOTHING was optimized. I basically did batch conversions for all the images at once.
After doing the raw conversion, I cropped to the red rectangle and converted (via Raw Converter) each image to a TIFF. The images from each camera were then sized to 345 x 345 pixels and placed in conjunction with the corresponding images in Photoshop CS4. There was a little downsampling required for the D3x images compared to the D3 images – I did that in Photoshop using the bicubic sharpening sampling protocol (found in the image size dialog box).
The resulting images were very usable, especially when viewed at 100 - 200% on my screen. Unfortunately, when I first uploaded all of these images, I found that at the size I prepared for my original post, you really couldn’t see the noise patterns very. So, for purposes of this test, I rezzed up each image in Alien Skin Blowup 2 to 1600 pixels across the horizontal margin.
