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Comparing features
Fixed lens digital cameras are sometimes referred to as ‘Digicams’, ‘Prosumer cameras’, ‘Bridge cameras’ or ‘EVFs’ (an acronym for ‘Electronic ViewFinders’). There is no traditional name because this is an entirely new breed of camera where typical examples in the genre are neither compact nor feature the mirror and pentaprism mechanisms to enable them to be called an SLR.
The quality and list of professional features that these cameras boast has been growing over the last few years and the spec sheets have raised more than a few eyebrows amongst professional photographers. Although the size of these cameras has been growing (largely in response to the huge optical zooms that are integral to most of the models on offer) their price point has pretty much remained the same. Many sophisticated fixed lens cameras have sensors that are capable of capturing more than 8 megapixels and have a 10x (or greater) optical zoom range. With the arrival of these impressive lenses the need to change a lens (which is obviously not possible if the lens is fixed) has been rendered a non-issue. In fact the inability to change the lens can be viewed as a positive point when you consider the ‘dust on the sensor’ issue* that is problematic for some DSLR users.
The one thing you cannot describe these prosumer-level digicams as is ‘compact’. Many of these super-zoom digicams are either about the same physical size and weight as some of the lighter DSLRs (Sony Alpha 100, Olympus E-500, Pentax ist and Canon EOS 400D - to name but a few).
* Some DSLR cameras have addressed the problem of dust by using sensors that utilize an anti-static coating and/or a sensor that vibrates to shake the dust off when the camera is switched on or off.
Image stabilization
Many fixed lens cameras now offer some form of ‘image stabilization’ or ‘anti-shake’ technology. This allows hand-held shots in low light or at the limit of telephoto extension. Image stabilization is not unique to fixed lens digicams - professional DSLRs also feature this technology and while Sony build an anti-shake system called ‘Steady Shot’ into the DSLR camera body, Canon’s IS system (image stabilization) and Nikon’s VR system (vibration reduction) are designed into their pro-grade lenses.
If you intend to use a camera for classic telephoto purposes such as wildlife or sports, this may be important to you. It is also useful for hand-held portrait shots in available light. However, it is worth remembering that image stabilization may only remove the shake in your own hands and if the subject is not absolutely motionless then motion blur may still occur. It’s also worth bearing in mind that the image stabilization system itself may introduce unwanted artifacts to an image.
Viewfinders and LCDs
Single lens reflex (SLR) cameras use a mirror and pentaprism design to display an optical view of your subject in the viewfinder prior to capture. The view is typically bright (especially if you have a wide aperture lens fitted) and detailed so that you can focus the image easily and quickly if you have to switch to manual rather than auto focus.
The image is not a ‘what-you-see-is-what-you-get’ image as feedback on issues such as how the sensor will handle the subject contrast together with the effects of your choice of exposure and depth of field are not being previewed. A depth of field preview button is available on some DSLR cameras that allows you to preview the image with the aperture stopped down to the one that will be used to capture the image rather than the widest aperture which is normally used to provide the optical view.
Although useful in some instances the subject can appear very dark in the viewfinder, making precise depth of field difficult to determine. This information is now more easily viewed on the LCD screen and not in the viewfinder after the image has been captured. The prosumer digicam, on the one hand, has no mirror, pentaprism and usually no optical viewfinder.
The LCD view on the fixed lens digicam, on the other hand, is a ‘live view’ - a miniature version of what you will actually capture. Its advantage is that it includes information about depth of field, exposure and contrast. This ‘what-you-see-is-what-your-get’ view is usually only available on a DSLR camera after the image has been captured.* The disadvantage of an LCD view is that it can be hard to see in some lighting conditions on location and can make manual focusing difficult or impossible.
*Olympus and Panasonic make digital SLR cameras with a second sensor to provide this live view. |