Nikon’s D40x D-SLR; A Sibling To The D40, But With Higher Megapixel Count

If you run down the specs of the Nikon D40x D-SLR and compare them with the D40 you'll not find many differences. This is essentially the D40 with 4.1 more megapixels on the same size sensor and the ability to use ISO 100, rather than the ISO 200 lower limit on the D40. (To see the D40 review and specs visit and type Nikon D40 into the Search box.) The D40x sells for about $130 more than the D40 (street prices).

So, you might ask, why do a separate review? Indeed, we'll forego the usual specs and features section of the review, as there's little sense in reiterating them here. We'll instead focus on just what an extra 4 megapixels gets you. We'll also take a look at some of the current Nikon AF-S lenses and the SB-400 flash, this being, like the D40, a body that only will support full functionality on those lenses that have an AF-S designation (motor in lens). Yes, you can use other Nikkor mount lenses, but non-AF-S lenses will not autofocus (we can live without that) or, in some cases, with non-CPU lenses like older Nikon manual-focus types, not even allow for metering (fine if you have a handheld light meter still kicking around). In short, the D40 and D40x are for those making a purchasing decision not based on having "legacy lenses," or those who do have AF-S optics.

Given that this camera is in the D40 class, it is marketed heavily toward families with kids who are fed up with the shot-missing shutter lag of digicams. In that it works very well and is a good beginner D-SLR for those who might want to get larger prints from their family pics or, as here, crop from full frame for excellent 8.5x11" prints. This shot was made with the D40x and Photo Basics lighting setup (see our review of those lights in our May newsletter, available at, or receive it free each month via a sign-up on our website).
All Photos © 2007, George Schaub, All Rights Reserved

The body build, shape, size, and functionality are the same on both cameras, with similar controls overall. LCD size has not changed, and the format options (various JPEG levels, NEF, and NEF+JPEG) are the same. But when you choose JPEG and/or NEF you now get a 30+MB file size, as opposed to an 18+MB file from the D40. And yes, D40x NEFs do not have the same structure as those from the D40, so those who do their converting in other than Nikon software will have to use a raw converter update to see and play with their raw images. The NEFs are 12 bit, and allow for all the manipulation features any raw file offers.

I have to admit that I have not used Nikon's Capture software for a while, relying instead on Camera Raw in Photoshop. But the update on Camera Raw for the D40x was not ready at the time of this writing, so I was forced to rely on Capture for my NEF processing. While not as elegant on the graphic side as Lightroom or Aperture, I was very impressed with the capabilities and EXIF data Capture offered. While optional (about $100 street) dedicated Nikon shooters would do well to consider it as their raw processor and converter.

So, just what does 4 megapixels extra get you? If you think in terms of print size, when converted to TIFFs, the D40x can yield a "straight" 11.5x17" print when done at 240 ppi, which is the recommended, average setting for most printers. Some printers feel you can get away with even lower ppi settings with a file this size, so let's call it 13x19" to match some of most popular desktop sizes. The D40, at 6 megapixels, could yield an 8.5x11" print, given that at the smaller file size you go for 240 ppi and generally don't want to stretch the ppi much further. But max print sizes are not the only way to judge the difference--you should also consider the possibility that some image cropping might be done in the process. So it is true that more megapixels, given all other things being equal, will allow for more printing flexibility and overall size.

You should also consider the fact that when you pack more pixels onto a chip of the same size you are decreasing the light-gathering ability of those pixels, and possibly the noise level at higher ISOs and other conditions that could increase noise. The D40x allows you to shoot at ISO 100, while the D40 is at a minimum of ISO 200. Something in the chip/image processor has changed, and that something is proprietary. The clue is what happens at higher ISO settings, so that became an important part of our tests, to see if higher ISO settings were tolerable in terms of noise.

AF-S Lens Options
The lenses we got to work with, including the kit AF-S Nikkor 18-55mm, were the AF-S Nikkor 55-200mm f/4.5-5.6G ED VR (about $250 street) and the AF-S Nikkor 12-24mm f/4G ED (around $900 street). Both are DX lenses, which means they can't be used on your Nikon 35mm SLR, and both offer Nikon's standard 1.5x multiplication factor. Both lenses are very lightweight and silent and fast in their autofocusing operation. In terms of carrying a kit around with the D40x body on travels, I cannot think of a better combination, for this price, than these two.

At ISO 400-800 you can choose to have NR (Noise Reduction) processing done in camera, or not; at above ISO 800 you can't. The ISO 1600 shot here (below top) isn't too bad, given you can accept shadow noise, some artifacts, and increase in contrast. In short, the image processor does a pretty good job. But you can always do more noise reduction in Nikon Capture, which allows for a good balancing act between the Intensity of the NR and the Sharpness of the image (right). But be aware of overuse of the filter, here exaggerated to show how going too far can soften the image to the point of giving it a "plastic" feel (below bottom).

True, the speed on the long end of the 55-200mm lens is not great--effectively f/5.6 at 350mm. This means you will usually have to boost ISO in anything but bright light to ensure a steady shot. You can boost the D40x to ISO 400 without much pain (just a bit of heightened contrast) so that's one way around the fairly slow long end. My rule at that focal length (and frankly I'd always trim back to less than full extension for best results) is about 1/500 sec minimum. For this lens at max aperture (not always the best place to be either) that is one stop short of the "sunny 16" rule. The lens is VR, and that helps, but if you have the bucks opt for something faster in the same general focal length range. Minimum aperture at the long end is f/32, so moving back to f/16 will give you plenty of depth of field and best results.