Good Image Quality on a Tight Budget – The New K-X and Some Lenses For It

By Joe Kashi

Someone recently inquired about which cameras and lenses we thought would provide the best image quality without breaking the bank.

Get a good entry-level digital Single Lens Reflex (dSLR) camera and a decent lens or two. That’s it in a nutshell.

Manufacturers introduced nearly 150 “new” compact and consumer cameras during 2009 and nearly one hundred in January 2010 along. Even the better ones now cost $300-$500, their image quality is noticeably deficient compared to almost any current dSLR.

At the same time, dSLR cameras have become much better, somewhat more compact, and MUCH less expensive. As a result, we’re at a cross-over point. A decent entry-level digital SLR cameras now cost perhaps $100 to $150 more than an expensive compact camera like the Canon G11, Canon S90 or the Panasonic LX3 but the dSLR’s image quality will be better and the dSLR will be more versatile.

The only real tradeoff is that the dSLR will be larger and heavier. If you’re on a budget, though, and want quality photos, then this is a very sensible tradeoff. Even though I really like using high end compact camera, whenever economics force a choice, I would definitely choose a dSLR camera rather than a high end compact like the Canon G11.

Overall, the optical quality of any camera’s lens is at least as critical to good images as the internal sensor. A poor lens is always a poor lens. At the same time, although you change to a better lens on a dSLR, you’re permanently stuck with whatever sensor is built into your camera, so choose your camera carefully.

There are a few compact dSLR cameras whose bulk and weight are not overwhelming. Choose one of these if compact form is important to you. Fortunately, two of the best compact dSLR cameras, the new Pentax K-X and the Olympus E620 are also among the least expensive, most compact, and have some of the best “kit” lenses.

The standard Olympus , the 14-42mm zoom, is unusually sharp for a kit lens and the E620's Four-Thirds sensor has decent image quality. However, the E620's Four-Thirds sensor is only about one-half the size of the standard APS-C sensor and thus may be slightly noisier than cameras using an APS-C sensor.

Of the APS-C compact cameras, there’s a lot of excitement about the new Pentax K-X ($540 with basic 18-55mm AL kit lens, from Amazon). The K-X uses a new, highly regarded 12MP Sony sensor in a compact and capable body. This is the same sensor that Leica uses in its new $2,000 X1. The K-X inherits many semi-pro features from the Pentax K7.

Given the relatively low price of the K-X, one realistically should not expect a metal body and complete weather sealing. The K-X uses standard SD cards and rechargeable AA batteries, which are available in any supermarket if you run short away from home.

Should you require a more rugged body, semi-pro features, and weather sealing, then for an extra $130, Amazon will sell you the semi-pro along with the rather better Pentax 18- 55mm AL II kit lens. The K20d is also an excellent budget choice.

Pentax makes a number of basic lenses that may suit your needs without breaking the bank. The basic K-X kit lens is the 18-55mm AL lens, which is OK but nothing special. Once you’ve made the decision to go with a particular dSLR camera, then buy it with the best available kit lens. You're paying hardly anything for the kit lens, so you can always put it in a dark drawer with a clear conscience if it’s not satisfactory.

The Pentax 18-55mm AL II kit lens costs about $115 if separately purchased at Amazon. It’s a step up from the basic 18-55 AL lens and is worth the extra cost. Pentax also makes an 18- 55mm weather resistant (WR) kit lens ($170) for sealed semi-pro cameras like the K20d, and K7. Optically, it performs on par with the basic Pentax 18-55mm AL kit lens.

Pentax makes three other zoom lenses in this range, the 17-70mm f 4 DA (about $480), the 16- 50 f 2.8 DA* (about $700), and the 16-45mm DA ($325 from Amazon). We can exclude the $745 16-50mm DA* from any article about getting the best possible value for your money. The 16-50mm, although weather sealed, is just too expensive. Optically, it’s only somewhat better than the 17-70mm and 16-45mm lenses

The other two Pentax normal range zoom lenses are very good lenses and not over-priced. The real question is whether they provide the financially constrained photographer with enough additional image quality compared to the 18-55mm AL II kit lens. The 18-55mm AL II lens is not exceptionally sharp at wide apertures but it’s a good outdoor lens that is quite sharp at smaller apertures like f 8 or f 11. The Pentax 17-70mm normal range zoom has been lauded in professional lens reviews. The 16-45mm zoom is more than adequate for all but the most critical work. I use my 16-45mm zoom regularly. It’s probably the best choice as a reasonably priced upgrade from Pentax kit lenses although the 17-70mm zoom is more flexible.

You’ll probably also want a telephoto as part of your budget kit. Pentax makes two light consumer grade zoom lenses, neither of which I found very satisfactory. The light weight 50-200mm zoom lens sells for about $175 and is included in many kits. Unfortunately, it’s not a very sharp lens. The other Pentax telephoto zoom is the compact 55-300mm zoom. Although the Pentax 55-300mm lens is better than the 50-200mm zoom, I have not been entirely satisfied with its performance in real life photos. It's not a bad lens but it is noticeably less sharp as you move away from the center of the frame.

Avoid zoom lenses with a wide zoom range, such as 18-250mm. Such lenses are difficult to correct over such a wide optical range and,as a result,tend to be fairly soft over much of their magnification range. You’ll typically find that zoom lenses with no more than a 3X or 4X magnification range will provide not only the best image quality but also be less expensive.

Pentax makes two fabulously sharp telephoto zoom lenses, the 50-135mm ($820) and the 60- 250mm (about $1,300). These are superlative lenses, as is Pentax’s widely praised 12-24mm wide angle zoom lens ($730), but all three are too expensive for anyone facing significant financial constraints.

The only really inexpensive telephoto zoom lens with good performance is the Tamron 70- 300mm Di LD zoom ($155 at Amazon). This lens is sharpest when the aperture is stopped down about 2 stops from wide open. It’s sharper than most name brand zooms in this general price range and does well until it softens near the upper end of its zoom range between 200-300mm, just like most telephoto zooms.

Our recommendation: We suggest the new Pentax K-X camera with the Pentax 18-55mm AL II kit lens or the 16-45mm zoom and the Tamron 70-300mm Di LD telephoto zoom lens for maximum versatility and good image quality on a tight budget.