Pentax K100D Digital SLR Review

Pentax K100D Jumpstart DVD just £14.99

Pentax caused a bit of a stir when they announced the K100D, which is their first digital SLR camera to include a CCD-shift camera shake reduction system. In this review, Gary Wolstenholme takes a look at whether this entry-level camera will shake up the marketplace.

Specifications CCD-shift Shake Reduction system 11-point AF Auto sensitivity up to ISO3200 2.5inch LCD screen 6.1 megapixels Penta-mirror viewfinder Shutter speed range 1/4000sec to bulb 2.8fps continuous shooting SD memory card compatible Price - £599.99 with 18-55mm lens

Build and handling Although the K100D is made mostly of plastic, a combination of a lightweight metal chassis and the use of a special fibre-reinforced plastic for the external construction, makes the body feel rigid and sturdy. A soft rubber coating around the fingergrip further improves the handling, which is excellent for such a compact SLR. The camera feels well balanced with most lenses I tried, including a telephoto zoom and a macro lens.

Display screens and viewfinder The fantastic pentaprism viewfinder present in the Pentax *ist DS has not been used in this camera. The viewfinder is clear, and although it could be brighter it is easy to confirm focus. The 2.5inch LCD screen on the rear is bright and clear, although the shiny hard plastic cover makes it difficult to see the screen in bright light. If you need to check the exposure or composition of an image, I'd recommend finding a shady spot. This isn't always ideal and their are other solutions available from the ePHOTOzine shop, such as screen shades and anti-reflective covers.

Menu and controls
Anyone who has used a Pentax digital SLR before will feel completely at home with the controls. The menu buttons, exposure mode dial and other controls will all seem very familiar. One improvement I like is the more prominent exposure compensation button. This allows for quick exposure adjustments when using one of the creative manual exposure modes.

The in-camera menu system is well laid-out, and easy to navigate. Controls such as colour saturation, sharpness and image tone can all be adjusted with a couple of button presses. Hidden deeper in the menu are more advanced options, such as the custom functions menu. This includes options such as noise reduction, exposure steps, auto ISO range, link AF point and AE metering, meter operating time, OK button functions, manual white balance measurement and the colour space used. Once you've found this menu it is a good idea to go through and have a look at the default settings, as some of them may not be to your taste.

One feature that will delight users of older Pentax cameras, is the ability to use manual focus lenses with centre-weighted metering in Aperture priority or Manual exposure modes. The option to enable this is hidden in the custom functions under, "Using Aperture Ring". When this is enabled, aperture values can be set on the lens. The Shake Reduction system also needs to know what focal length the lens is, this can be input in the settings menu.

Battery
The K100D is powered by four AA cells, The advantage AA batteries have over proprietary lithium batteries is their availability. They are available worldwide, so if you run out of power you can nearly always buy fresh ones.

There are three main types of battery to choose from, Alkaline, NiMh rechargeable and CR-V3 lithium cells. CR-V3 batteries give the longest life, but with a high-street price of around £10, they can work out expensive. Rechargeable CR-V3 batteries offer the best of both worlds, giving long-life while being economical. Some rechargeable CR-V3 kits are available from the ePHOTOzine shop.

The battery door is flimsy, and can easily be mis-aligned if changing batteries in a hurry.

Lens system

Around twenty different autofocus Pentax K-mount lenses are currently available ranging from exotic fisheye zoom lenses to lightweight telephotos. Third party manufacturers, such as Sigma and Tamron, also offer a comprehensive range of lenses. As the Pentax K-mount used on this camera has remained pretty much the same over time, a large selection of lenses can also be bought second-hand, which can be great for photographers on a budget.

Flash system

A small pop-up flash is built into the K100D, which is great for providing a little fill-in outdoors, or as a last resort when light levels fall. The K100D also accepts the range of digital compatible Pentax flashguns. These include the AF 360 FGZ which has a guide no of 30(ISO 100/m) and costs about £200, and the more powerful AF 540 FGZ, which has a guide number of 54(ISO100/m) and costs over £300. For the latest prices please check the ePHOTOzine shop.

A white wall shot using the on-board flash at 18mm, adjusted in levels to illustrate flash coverage. Fall-off gradually increases towards the corners and is more prominent at the bottom of the frame, but is smooth and barely noticeable in normal circumstances.

Memory card
The K100D uses an SD memory card which fits into the slot on the side. The following are write speeds for various quality settings using a Sandisk Extreme III card.

Quality setting	Time taken to write to card
6 megapixel RAW	5.3secs
6 megapixel Jpeg fine	2.8secs
6 megapixel Jpeg normal	1.6secs

I also timed the delay between shots with this camera in the single shot mode. I measured this by taking five shots in quick succession and working out the average delay.

Quality setting	Shot-to-shot delay
6 megapixel RAW	3.66secs
6 megapixel Jpeg fine	1.25secs
6 megapixel Jpeg normal	1.22secs

Write speeds and the length of the shot-to-shot delay are quite respectable when shooting Jpeg, but not so great when shooting RAW. The camera only appears to have a three shot buffer for RAW images, this means that if you are taking shots in quick succession you have to wait for enough space to clear in the buffer before you can take another.

Shooting
An 11-point autofocus system allows for creative composition of off-centre subjects. The AF are not visible until one is elected, or the camera is focused, which I found a little disconcerting at first. When you get used to where all the points are this becomes less of a problem. Quite a wide area of the viewfinder is covered by these AF points which is great. When a point is selected, it lights up red and is clearly visible in all lighting conditions. Occasionally there can be quite a long pause between the camera focusing, and allowing you to take your shot in Single-Servo AF. I found this frustrating, especially when shooting moving subjects.

	Left - The automatic metering has coped well with this difficult scene, retaining detail in both highlights and shadows. Above - The automatic white-balance tends to give a warm magenta cast to images, which is great for portraits.

The Anti-shake function is useful, although there is no indication of the system working, or how effective it may be, except for the finished image. I find this disconcerting, and even found myself checking whether it was active or not. The system does provide the claimed 2 stop advantage in most circumstances, although the system struggles with close-up pictures.

Image quality

All images for this review were taken at maximum resolution using the fine JPEG compression setting. There are several different compression levels and resolution settings including RAW to choose from allowing you to select the setting most appropriate for your needs.	Images display punchy levels of contrast and a good level of detail.
Colours are strong, without becoming over-saturated.	Dynamic range is wider than previous Pentax models I have used.

Digital noise

The following images illustrate the amount of digital noise apparent at each ISO setting. The image to the right is the full image. The crops below are taken from where the green square is.
ISO200	ISO400
ISO800	ISO1600
ISO3200

ISO200 and ISO400 both produce very clean images, and even by ISO800 noise levels are well controlled. Images taken at ISO1600 have more noise present, but not excessive amounts. Things start to get messy at ISO3200, this sensitivity should be reserved for when nothing else will do as the level of noise will be clearly noticeable, even in smaller 6x4inch prints.

Compared to...

Pentax K100D at ISO1600

Samsung GX-1S at ISO1600

Canon EOS 5D at ISO1600

The K100D performs well for its price point. Noise levels are acceptable, being better than the Pentax-based Samsung GX-1S. The Canon EOS 5D outclasses the Pentax, but then it should do, it costs around three times the price of the Pentax.

Detail comparison

This busy scene was taken using a tripod to determine the level of detail this camera can produce.	Pentax K100D set at ISO200 using a Pentax DA 18-55mm lens set at 18mm and f/16
Samsung GX-1S set at ISO200 using Schneider D-Xenon lens set at 18mm and f/16	Olympus E-330 set at ISO100 using the Zuiko 14-45mm lens set at 14mm and f/16

The K100D performs well for a six megapixel camera producing a sharp image with plenty of detail. The eight megapixel Olympus E-330 appears to be matched, as any difference in the amount resolved is negligible.

Verdict
If you're looking for your first digital SLR, the Pentax K100D is well worth a look. The Shake Reduction, easy controls SD card compatibility and lightweight design make this camera ideal for those looking for a step up from a compact digicam. Photographers who travel will also appreciate these features, as well as the ability to use AA batteries. Existing Pentax SLR owners may also wish to upgrade, whether it is from a film or earlier digital SLR.

If however, you're requirements are more demanding, you may get frustrated with stuttering AF system and the small buffer when shooting RAW files.

In summary the positive points of the Pentax K100D are:
Great build quality for a lightweight digital SLR
Takes AA or CR-V3 batteries
Images are colourful and contrasty straight from the camera
Better dynamic range than previous Pentax's

The negative points:
Pause between focus and shooting in Single Servo AF
Shallow buffer
Flimsy battery door

Check the latest prices for the Pentax K100D in the ePHOTOzine shop

Click here to see photos taken with this camera by ePHOTOzine members

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