Digital Camera Features
Features to look out for when choosing a digital camera include:
Most modern digital cameras, mirrorless and digital SLR cameras, have sensors with 10 million pixels or more. These cameras are more than capable of printing up to A4 or A3 color or black and white prints. Many cameras offer the facility to change the resolution if a low resolution image is required i.e. for web pages. Images are commonly saved in the JPEG (Joint Photographers Expert Group) file format which compresses images to balance file size and image quality.
Most point and shoot digital cameras have a zoom lens which goes from wide angle to short telephoto & is usually the equivalent of a 28 - 105mm zoom lens on a 35mm camera. These lenses can go wide enough to shoot small groups and then zoom in for a portrait at the telephoto end. Over recent years, super zoom digital cameras have become very popular for travel, sport and general photography. These cameras have zoom ranges from 24mm to 1000mm or more. Unfortunately many of these super zoom cameras have small sensors which limits image quality as well as low light photography capabilities. A small number of compact cameras now have one inch sensors and a large zoom range up to 600mm or more. These compacts offer photographers the ideal combination of portable size, low weight, bright powerful zoom and a large sensor for high quality images. Ultimately, mirrorless and digital SLR cameras offer the highest quality images through their large sensors and interchangeable lenses which provide the greatest choice from super wide fish eye lenses to huge telephoto lenses. On the downside, they can be large, expensive and heavy to carry.
This is the time it takes to press the shutter and for the actual picture to be taken by the digital camera. Pressing and holding the shutter halfway before releasing it fully can reduce the time dramatically on most point and shoot digital cameras. Unfortunately there are still many digital cameras that can take .5 to 1 second to take a photograph. Shutter lag is virtually non-existent on digital SLR cameras, mirrorless cameras and on some compacts.
Many digital cameras, especially point and shoot, offer limited control by including scene modes such as portrait, night, flower, snow, beach and many other categories. These are usually in addition to the program mode.
A small built in flash is a common feature on nearly all digital cameras and can light up a subject when lighting levels become too low. The flash range is normally 3 to 5 meters. Some prosumer and professional digital cameras have a hot shoe which allows a more powerful flashgun or studio flash to be attached.
Digital cameras are dominated by four types of viewfinders:
Optical - a small window which can feel like looking through a small tunnel.
LCD - a small TFT screen on the back of the camera ranging in size from 2" to 3" or larger. Many LCDs today accurately frame a picture by showing 100% of the scene. Some cameras offer both optical and LCD viewfinders.
EVF - Electronic viewfinders are used on some prosumer cameras with long zooms with most showing 100% of the scene. Some older viewfinders can suffer from a slight lag when any movement is involved. Newer OLED viewfinders with 2.36 million dots offer superb clarity with virtually no lag.
Pentaprism - most SLRs use a pentaprism or pentamirror to project an excellent and clear image to the eyepiece.
Options such as aperture priority, shutter priority and full manual control are available on higher end digital cameras and some low cost enthusiast compacts. These features allow a photographer to take control of the camera's exposure and are a great learning tool for the amateur and enthusiast. All digital SLR cameras come with manual controls for greater photographic control.
There are a wide range of proprietary batteries used by camera manufacturers with some cameras using the commonly available AA batteries - both alkaline and Nimh rechargeable. Proprietary batteries are often lithium rechargeable batteries and these can be expensive. It is advisable to carry a spare battery - even for digital cameras with a long battery life of 300 shots or more.
These come in all shapes and sizes ranging from 2 gigabytes to 1 terabyte or more. Some of the most commonly used formats include SD (Secure Digital), SDHC (Secure Digital High Capacity), SDXC (Secure Digital Xtra Capacity), Micro SD and compactflash. Some cameras come with small amounts of built in storage which will allow photographers to save a few images but it will be necessary to purchase a higher capacity memory card for storing large amounts of image and videos.
Digital camera movie modes used to vary enormously but now, many cameras offer high definition 720p or 1080p video with a select few offering 4k video. Some video formats can take up large amounts of space on a memory card and even a 10 to 15 minute movie will take up a few gigabytes of space. Cameras offering MPEG-4 movies allow high quality movies to be more efficiently compressed and take up far less space on a memory card without sacrificing too much quality. In general, a 1 gigabyte card can record one hour of MPEG4 but this may vary due to film format type and level of compression used. Many digital SLR cameras and mirrorless cameras now offer HD or 4k movie modes leading to a boom in amateur and professional film makers.
Other features which may be of interest to some users include:
Weatherproofing - allows cameras to be used in the rain or on the beach as they have weather proof seals. Some cameras are also waterproof upto a certain depth while camera housings can offer this facility to other cameras.
Image Stabilization - this allows a user to handhold a camera (especially with a long lens) in lower light than a standard camera. Optical and CCD shift image stabilization cameras are more effective than digital stabilization which just involves raising the ISO and therefore making the pictures more prone to grain.
USB - the universal serial bus is the most common way to connect a camera to a PC to download images. USB is available in versions 1.1 which runs at 12mps and version 2 which runs at 480mps. USB3 has been released recently and this runs at 5Gbp/s. It is also backwards compatible with USB2.