Features
The Sony Alpha 450 uses a 14.2-million-pixel CMOS APS-C-size sensor to capture images. This sensor was first used on the Alpha 350, and has since been included in the Alpha 380 and Alpha 550 cameras. Image processing is handled by Sony’s Bionz processing system, which is found in all its cameras. This enables the use of such features as in-camera dynamic-range optimisation and the in-camera creation of HDR images, but more on these later.
Unlike Canon and Nikon, which uses lens-based image stabilisation, Sony makes use of an in-camera, sensor-based system known as SteadyShot Inside. The advantage of this is that camera shake can be prevented in all images regardless of which lens is used.
The downside, however, is that the effects of sensor-based stabilisation cannot be seen in the viewfinder when shooting. To help get around this problem, Sony has included a SteadyShot scale indicator, which is displayed in the viewfinder and measures how much the camera is moving while in use, allowing the user to time when best to press the shutter to capture a blur-free image.
Having inherited much of its technology from Konica Minolta, Sony therefore uses the same lens mount on its DSLRs, although it is now known as the Alpha mount. It is a credit to Sony that there is already a full complement of lenses available to accompany its cameras. Better still, the company has Carl Zeiss designing and producing a range of high-quality lenses to accompany its own high-end G and standard series of lenses.
Sony also holds an 11% share in Tamron, and it is reasonable to expect that some of its lenses are designed and produced in association with this firm.
When it comes to saving images, the Sony Alpha 450 can use either Sony’s own Duo Memory stick or the more common SD/HC card. It is also possible to view images on a television via the Alpha 450’s HDMI cable socket.
If you are fortunate enough to own a Sony Bravia television with HDMI input, you can take advantage of the fact that each image file produced by the Alpha 450 has a built-in preview image. The size, colour and contrast of these preview images are specifically designed to be viewed on Bravia televisions.
One of the more interesting features of the Alpha 450 is the speed priority shooting mode. This allows up to seven frames per second to be captured, but it sacrifices focusing between shots. Consequently, the mode is only really suitable for subjects with a restricted zone of movement. For example, a footballer could move completely in and out of focus across seven shots, but a tennis player about to hit a ball will be positioned on roughly the same spot throughout, so if a small enough aperture is used a good level of focus should remain.
When in the standard continuous high shooting rate, the Alpha 450 is capable of an impressive 5fps for 32 JPEGs, 14 raw images or seven raw + JPEG images. In all, the Alpha 450 is a well-specified camera for its price. Although it lacks a few bells and whistles, there are enough features included, such as in-camera stabilisation and a fast shooting rate to satisfy the needs of enthusiasts.
Feature in use in-camera HDR
High dynamic range (HDR) images have been popular for some time. Until recently, we have only seen dynamic range optimisation effects in DSLRs. However, Pentax and now Sony have introduced fully fledged HDR imaging in the cameras themselves.
In the Alpha 450, the HDR feature is available in the D-Range menu. The camera takes two exposures in quick succession with a single press of the shutter release and each image has a different exposure. It then processes and combines these two images into one final processed image that merges the highlight detail from the darker image and the shadow detail from the lighter image.
In the Alpha 450, you can specify an exposure difference between the two images of between 1EV and 3EV, at intervals of 0.5EV. Alternatively, you can let the camera automatically decide the exposure for you. The greater the difference in EV between the two images, the more dramatic the HDR effect. For example, for a subtle lifting of shadow areas you may wish to use the 1EV setting, but to produce an image where much of the image is nearly a midtone you would be better off using the 3EV setting.
The HDR effect can be used handheld as the camera aligns the images as best it can during the processing stage. Of course, if the camera or something in the image moves, the processing won’t be able to align the image accurately and the result is a ghosted effect. For this reason, it is always advisable to use a tripod if your images require a slow shutter speed.
As the HDR image is a processed effect it can only be applied to JPEG images and not raw files. This presents a number of possibilities for creating some interesting in-camera effects. For example, you can set the image style to vivid and the effect to its maximum 3EV setting to produce a bold and bright picture. It also works with black & white images.
Used at its minimum setting of 1EV, it can be used almost as fill light, or for effectively dodging the shadow areas of an image. At its maximum strength, images are very flat in terms of contrast and look like etchings.
