Buying a second DSLR – Pentax
The K-x is the natural choice for Pentax users who are looking for a second DSLR to augment their K20D or K-7.
Pentax appears to have been preoccupied with producing small DSLRs since the K20D was launched, and the K-7 is considerably smaller than the Nikon D300S and Canon EOS 50D that it is
designed to compete against. The K-x, Pentax’s entry-level model, is even smaller and lighter, but it still has a pronounced, comfortable fingergrip.
Thanks to their extensive weatherproofing, the K20D and K-7 have a reputation for being cameras that can be used almost anywhere. As the K-x isn’t quite so well sealed against the elements, K20D and K-7 users need to bear this mind when planning to use it as a second body in bad weather.
Image quality
Although the K-x has around 2.2 million fewer pixels on its APS-C-sized sensor than the K-7, there is only a small drop in the resolution of the images it produces. Pentax tends to major on detail resolution with its enthusiast-level DSLRs, and in the past this meant high-sensitivity images were noisy.
Raw files from the K-x have quite a lot of chroma noise from ISO 1600 onwards, but they also have plenty of detail and the coloured speckling is fairly easily controlled using Adobe Camera Raw’s controls. Chroma noise is much less visible in JPEG files captured in the default noise-reduction settings than it is in comparable images from the K-7. This probably explains why Pentax felt confident enough to allow the K-x a sensitivity expansion setting equivalent to ISO 12,800 whereas the K-7 tops out at ISO 6400.
Given the wide compatibility of the cameras’ DNG raw files (PEF is also an option with the K-7 and K-x), and the fact that JPEG files from both cameras usually benefit from an application of Unsharp Mask, I recommend shooting images in this format whenever possible.
K-x
One of the stand-out features of the K-7 is its self-levelling sensor. While the K-x doesn’t have this, or a digital level, most enthusiast photographers understand what is required to ensure the horizon is straight. The Pentax Dust Removal (DR), Shake Reduction (SR) and HDR systems, however, are present.
Image: In HDR mode, the K-7 and K-x automatically combine three images
As it takes globally available AA batteries, the K-x is a great choice for remote shoots where it can be difficult to access a power point to charge a lithium battery.
Pentax isn’t really known for its AF systems, but the K-x is equipped with one of the best we have seen. The SAFOX VIII module appears very similar to the SAFOX VIII+ unit in the K-7 and features 11 individually selectable AF points, nine of which are cross-type.
Focus is achieved quickest with Pentax SDM (Supersonic Drive Motor) lenses.
Image: Like the K-7, the K-x has an interactive shooting menu for quick settings changes
Live View
One of the criticisms levelled at the K20D was that it has a pretty poor implementation of Live View. Fortunately, this was addressed along with the addition of 720p (1280×720-pixel) video recording for both the K-7 and the K-x, and this makes the K-x a particularly good second body option for K20D users.
However, while the K-7 has a 3in, 920,000-dot (307,000-pixel) LCD screen, the K-x has a slightly smaller 2.7in unit with just 230,000 dots, which means details aren’t quite as clear and it may take a little longer to be certain that the focus is exactly where it should be.
Viewfinder
Although the K-7 has a 100% viewfinder, it is rather tunnel-like and the eye needs to be dead centre and straight-on as it is easy for the housing to obscure the corners of the scene. This means that dropping down to a viewfinder with 96% coverage isn’t a huge drama, although K-x users need to take care to avoid including unwanted elements around the edges of the frame.
Batteries
There are obvious advantages to owning two cameras that accept the same batteries. For a start, you can swap the batteries around and continue to shoot on your preferred model once its cell is depleted. It’s also only necessary to carry one charger when you are away from home for an extended period.
If, however, you have cameras that take two different batteries, it is worth considering investing in a universal charger such as the Ansmann Digicharger Vario Pro (£49) that has adjustable pins to allow it to be used to charge a wide range of different camera batteries as well as more common AA and AAA cells.
| K20D | K-7 | K-x | |
| Date tested | 12 April 2008 | 15 Aug 2009 | 5 Dec 2009 |
| Pixel count | 14.6 million | 14.6 million | 12.4 million |
| Street price | Discontinued | £795.99 | £419 |
| AF points | 11 | 11 | 11 |
| Max sensitivity range | ISO 100-6400 | ISO 100-6400 | ISO 100-12,800 |
| Memory card | SD/SDHC | SD/SDHC | SD/SDHC |
| Battery | D-LI50 | D-LI90 | AA |
| Grip | D-BG2 | D-BG4 | N/A |
