Information About Desktop Document Cameras
While portable document cameras are characterized by a compact design and ease of transportation, a desktop document camera is a more permanent and stationary document camera solution. One of the key characteristics of a desktop document camera is its large work surface, also called the document camera’s footprint. Digital presenters with this kind of larger work surface would typically be situated and used on a table or desk, which gives this type of document camera its name.
Desktop document camera design
The core design of a desktop document camera is very similar to that of any other type of document camera or visualizer, which means it has a CCD camera that is attached to a column, usually pointed down on to the work surface. Although desk top document cameras might be less easy to transport than portable document cameras, the bigger bases that desktop document cameras possess enable document camera manufacturers to add more functions and features to them. Although desktop document cameras are usually heavier than portable document cameras, to make transportation and storage easier a desktop document camera will often have one or more carrying handles and a foldable camera arm.
Desktop document camera image quality
While portable document cameras may have an advantage over desktop document cameras in terms of how easy the document camera is to transport, the image quality of a desktop document camera is usually much higher than that the image quality of a portable visualizer. Generally desktop document camera image quality will range from SVGA resolution (800 by 600 pixels) all the way up to WSXGA resolution (1680 by 1050 pixels), and can be anything in between. Higher end manufacturers of desktop document cameras such as those document cameras made by Wolfvision are capable of offering a high definition TV (HDTV) 720p resolution (1280 by 720 pixels) and an HDTV 1080p resolution (1920 by 1080 pixels) desktop visualizer.
Desktop document camera lighting and illumination
To allow the subject matter being viewed by a desktop document camera to be illuminated properly, many desktop document cameras employ an overhead lighting feature, which is the most common lighting method for desktop document cameras. Overhead lighting solutions often have three ways in which the lighting can be configured:
Adjustable lights to the left and right of the base stage
A solitary adjustable light positioned near to the camera head
A fixed light positioned at the back of the base stage
In a number of desktop document camera models the base stage has a backlight built in to it which allows the desktop document camera to be used for viewing transparencies such as those which might be used with an overhead projector. The size of the document cameras backlight can vary from a 35mm slide frame size up to letter size.
Desktop document camera controls
The controls on a desktop document camera which are used to access the majority of the document camera’s functions are usually located on the front of the base stage, or at its back or side panels, which makes the controls easier to reach and use. On some models of desktop document camera the controls may be located on the camera head. In addition, a number of desktop document camera models may be supplied with wireless remote controls. Some desktop document cameras will also have a housing space where the remote control can be stored whenever the document camera is not being used.
Close up desktop document camera lenses
Some models of desktop document cameras may be supplied with a close up camera lens. This will depend on the depth of field of the camera’s lens. A close up lens will allow the desktop document camera’s camera to focus and magnify 2D or 3D objects which are positioned very short distances away, for example, the distance between the camera and the base stage.
There are two common ways in which these lenses can be fixed to the desktop document camera. The first method is using a "flip-up" fixing. This type of document camera lens fixing is where the lens is surrounded by a narrow frame which is then attached to the document camera’s camera head using a hinge attachment. This means that when an object needs to be viewed close up, the hinge simply closes up over the main document camera lens to magnify the object. When the subject matter is further away, the close up lens can be opened or "flipped up". Desktop document cameras which do not possess close up lenses may not need one due to the construction of the lens or the purpose of the document camera’s design.
Additional desktop document camera features
One feature which is starting to be used more and more in desktop document cameras is the LCD confidence monitor. These confidence monitors are small LCD monitors positioned on the document camera and ranging from 3 inches to 6 inches in size. The purpose of a document camera’s LCD confidence monitor is so that the person presenting is able to see what the image will look like on the screen before it is shown on the larger display device such as the TV or projection screen. This helps the presenter make sure that the image being displayed by the document camera is in the right place and in focus. There are currently two models of desktop document camera that offer this solution: the Elmo P-100 and the Wolfvision VZ-9.
If a document camera does not have an LCD confidence monitor, it may have monitor mount points which would enable an accessory monitor to be used to achieve the same confidence viewing results.
Desktop Document Camera Connectivity
Desktop document cameras are typically larger than portable document cameras, and so the choice of connectivity available for use on a desktop document camera is often not as complicated as it might be on a more portable digital presenter. The sheer size of the desktop document camera’s base allows for physically more inputs and outputs for the presenter to connect equipment to. This connectivity is one of the key factors that contributes to the actual price of the desktop document camera, along with the image resolution, the document camera’s function, and its design.
Desktop document camera video connectivity
- S-Video (4 pin Mini DIN) connectors
- D-sub 15 pin VGA connectors
- Composite Video (Phono/RCA) and BNC connectors
- DVI (Digital Visual Interface) connectors are becoming more popular in some document cameras.
- High-Definition multimedia Interface (HDMI) connectors are used in the case of WolfVision document cameras
Desktop document camera audio connectivity
- Phono/RCA or mini jack connectors
Desktop document camera PC connectivity
- USB 1.0/1.1 (12 Mbits/second) connection
- USB 2.0 (up to 480 Mbits/second) connection
- Network Connection 8P8C ports (often referred to as RJ-45 ports) are also available for PC networking connectivity in desktop document camera models made by Lumens Ken-a-Vision and WolfVision.
Desktop document camera remote control signals
Provided by:
- RS-232
- Infrared wireless control
- RF wireless or USB control