Scenes like this exist for only fractions of a second. It takes a camera with quick and accurate AF, exposure, and white balance to get the job done. Low noise at high ISOs comes in handy too. This was shot at 1/100 second, f/6.3 with a Nikon D7000 and 35mm f/2 AF-D Nikkor. It could just as easily have been shot with a Pentax K-5.
By now it's well-known among most photo-enthusiasts that the Pentax K-5 and Nikon D-7000 share the same Sony image sensor. This doesn't mean they produce identical results. The raw data from the sensor still has to be processed, both by the camera and by you, the photographer. There's also a big difference in their respective menus, exposure metering and AF systems, and control layouts. The result is that there are often significant differences in the way these two cameras perform in a given situation. Whether one is "better" than the other will, of course, depend on the situation and your personal preferences. The purpose of this quick comparison is to give you some insights into how well they perform in a fast-paced available light situation.
In this case the situation I chose is a veritable torture chamber: Reading Terminal Market, a 78,000 square-foot indoor facility in Philadelphia's Center City. It houses more than 80 merchants who sell local produce, meats, poultry, seafood, handmade crafts, jewelry, clothing, and more. The lighting varies from fluorescents to incandescents to neon, often all within the same area. It can be bright in some places, dim in others.
To make things even more interesting, the market is jammed with hundreds upon hundred of shoppers, many of whom constantly walk in front of you as you try to frame and compose a photograph. You and your camera both need to be quick and accurate to get an acceptable photo in this environment, which is precisely why I chose it.
Set-up
I wanted the comparison to be as equal and fair as possible so I set up each camera the same way:
- 35mm lens (35mm f/2.8 DA Macro for Pentax, 35mm f/2 AF-D for Nikon)
- Matrix/Multi-segmented metering
- Program exposure mode
- ISO 1600
- Multi-point autofocus in one shot (AF-S) mode
- Automatic white balance
- RAW format (PEF for Pentax, NEF for Nikon)
- Noise reduction at minimum setting
This was a bit more automation than I would normally use under these circumstances. For example, I would normally select only one AF point (the center) rather than let the camera do the selecting. On the other hand, I didn’t want to apply so much manual control that the exercise would become more a test of my problem-solving skills than the camera's abilities.
My modus operandi was to walk up and down the aisles of the market with one camera on each shoulder. When I saw an interesting scene I would try to shoot it with both cameras. I couldn't get exactly the same shot with both cameras. What I could get was real-world information on how each camera handled the same scene, framed the same way and with the same lighting. What follows are my impressions of how well each camera handled each of the key factors listed below.
Autofocus
At the light levels I was shooting at (EV 6 to EV8), the Pentax K-5 felt a split-second faster at acquiring focus than the Nikon D7000. There was, however, a catch: Even with all AF sensors active, the K-5 almost always used the center focus point, even when there were larger, off-center objects closer to the camera. In the same situation the D7000 would almost always focus on the largest, closest object. There were, however, exceptions, as illustrated in the photos below.
In this example the Pentax-K5 focused on the oranges in the foreground. Click to enlarge.
Given the same scene, the Nikon D7000 focused on the background. Oddly enough, in both cases the girl picking fruit is acceptably in focus. Also note the similarity in color response.
Neither result is necessarily better than the other. What matters most is where you want to place the point of focus and how easy it is to achieve the result you want. Under these circumstances I would normally prefer to use the center AF point and re-frame or select an off-center point that coincides with the location of my subject. If, however, I was shooting a sporting event, the D7000's ability to quickly lock and maintain focus on off-center subjects would be a decided advantage.
Keep in mind that I used both cameras with a 35mm lens only. The results with a fast-aperture 50mm or telephoto lens could be quite different.
Exposure
In most cases both cameras produced exposures that were within a half-stop of each other. More importantly, the exposures were remarkably good and consistent given the high-contrast light conditions. In cases were the exposures were different, the K-5 had more of a tendency to overexposes. Even then, the difference was no more than a half-stop. This would be easy to correct for anyone shooting RAW and a minor problem even for JPEG shooters.
White Balance
Unless you plan to convert to black and white and therefore don't care about color casts, a camera that can produce a reasonably accurate and consistent white balance in mixed lighting is a must. It's valuable even if you're shooting RAW; first, because it saves time in post-production, and second because it provides a consistent reference point for any later adjustments. A camera that shifts the white balance slightly from one shot to the next, depending on the framing, requires you to manually adjust the balance of each shot rather than a group of shots at once.
Here's how this scene looked straight out of the camera, just as the Pentax K-5 rendered it and with no adjustments in Lightroom.
Here's the same scene shot with the Nikon D7000. Once again, the default contrast is higher than the Pentax K-5 version. It should be apparent that with just a few small tweaks I could make the contrast of either image match the other.
Once again, the K-5 and D7000 were pretty evenly matched. Neither camera produced photos where the balance was obviously off. In some situations I preferred one camera's AWB more than other, but neither was superior and with some tweaking I could get a close match if I wanted to. Either camera also allows you to compensate for such shifts in-camera but I didn't feel the need and frankly wouldn't bother unless neutral whites and gray-tones were essential.
Image Noise
As I mentioned in the intro, I set both cameras to ISO 1600. I could have set them higher but I'm not a "bleeding edge photography" sort of guy. I'd rather push things only as far as necessary to get the results I want. In this case it was a reasonably fast shutter speed (averaging 1/125 second) to reduce motion blur and a moderate aperture (averaging f/4.5) to adequate depth-of-field. Both cameras allowed me to do this at ISO 1600 without a significant loss of contrast or color saturation and without shadow noise becoming intrusive.
Here's a crop of the Pentax K-5 image above. It's not quite 100% but close enough. Click to enlarge for a closer look at the image noise signature.
Here's the Nikon D7000 version. The foreground is slightly softer because the point of focus is further back, but what is in focus has plenty of detail, even at ISO 1600.
As you'll see from the accompanying photo examples, each one did this in a different way. The K-5 images have a smoother grain texture as compared the D7000 yet with a similar level of image detail. This is noticeable only on close inspection, meaning you'd barely see it even on a 16x20-inch print. It's also a matter of preference. Some may prefer the crisp B&W film-like grain of D7000 files to the slightly more color print film look of the K-5. Others may prefer the opposite. It's all good.
Dynamic Range
Here again there was little difference between the two. I was shooting RAW and as long as I was careful to avoid exposing by more than a stop there was plenty of image detail available if I needed. The fact is that more often than not I would increase the image contrast, especially when I was converting from color to B&W.
Handling & Responsiveness
The one area where the D7000 pulled ahead of the K-5, at least for me, was in handling and responsiveness. This was for one simple reason: When the K-5 goes into power-saving mode the only fast way to wake it up is to tap the shutter button. That’s fine if, like most photographers, you have the AF linked to the shutter button. If you’re a rear-button AF shooter like me you’ll discover that pressing the rear-AF button does nothing until you first tap the shutter button. I occasionally missed a shot because of this and, yes, it was annoying. I know I could increase the delay before sleep or turn off the auto-sleep feature entirely but this would decrease battery life. I prefer the D7000’s approach: Press either AF button—front or rear—and the D7000 instantly springs into action.
On the other hand, I greatly prefer the K-5's control placement over that of the D7000. The D7000's ISO button--a control I use often--is located along the left side of the rear display. On the K-5 it's just behind the shutter button. This position on the D7000 is occupied by the exposure metering option button, something I hardly ever use. I've devised a few work-arounds to reduce the need to press hard-to-reach buttons on the D7000. With the K-5 I don't have to.
Summary
If you're looking for me to announce a winner here, you're looking in the wrong place. You should be able to get practically identical and equally excellent images from either camera--and if you can't, you are most likely the limiting factor. I would give the edge to the Nikon D7000 only if you already own Nikon lenses or find the Nikon system, which is significantly larger than that of Pentax, more appealing. On the other hand, if you want a small but rugged camera that accepts a good selection of equally small but rugged and optically excellent lenses, you could do far worse than the Pentax K-5. Consider yourself lucky that you have such a choice and that you can't go wrong with either one.
