|
Key features and specifications for data projectors can be confusing and some of the details advertised may be misleading.
This document may help you to make a decision on the correct model to purchase, keeping in mind that the purpose for which you intend to use the data projector will help determine the features that you require and therefore the model that you choose.
Hints - The lamp replacement cost and estimated life span can affect running costs substantially.
The aspect ratio on the data projector you choose should align with the most commonly used hardware, such as those used in Education Queensland’s teacher laptop program.
In a school situation the lighting is often difficult to adjust hence a higher lumen rating is important.
Installing power and network connections in a school is both expensive and complicated - building age, structural design, interference with other utilities, as well as security and safety concerns may restrict the location in which the data projector can be mounted.
Lamps
Are fragile and expensive to replace. They carry a Watt rating and an estimate life span (in hours). They are also available in a variety of ‘types’ which are said to have different qualities. Be sure you know where/ how to buy replacements.
Power consumption
The power consumed when the data projector is in use. This has an effect on running costs and the environment.
Aspect ratio
Is the ratio between the width and the height of the picture, so a 16:9 is 16 units of width and 9 of height. 4:3 is most common and 16:9 is wide-screen. You should choose the ratio that best suits your most used hardware.
Contrast ratio
The difference between the quality of white and black eg. blacks are 300 times darker than the white on a 300:1 ratio. The contrast ratio on DLP panel projectors is much higher however colour is reported to be imperfect.
Display Resolution (pixel dimensions)
Is the number of columns and rows creating the display (pixels). Examples include: VGA 640 x 480, SVGA 800 x 600, XGA 1024 x 768, SXGA 1280 x 1024, VXGA 1600 x 1200 and can also be in widescreen versions if preceded by a ‘w’ eg. WXGA 1280 x 800.
Lumens
Is measure of ‘luminous flux’ or perceived power of light. A standard 100 watt incandescent light bulb emits approximately 1700 lumens. For a data projector less than 1400 lumens is only recommended in a room where there is reduced lighting.
Panels
DLP (Digital Light Processing) versus LCD (Liquid Crystal Display) – the new DLP panel projectors have a higher pixel “fill factor” which means that the pixels are closer together, so there is less space in between pixels and also usually have a higher contrast ratio. Many current projectors using DLP technology are using single-chip DLP, as opposed to newly evolving three-chip projectors, which can have visual issues for a small percentage of viewers, such as false flashes of colour.
Ambient Light Sensor
Automatically detects room brightness and adjusts operation accordingly
Software
Only some models come with software that usually enable various features including; Wireless and LAN connection, managing multiple PC input or multiple projector output, monitoring projector status, or enabling advanced displays including PiP (Picture in Picture) / PaP (Picture and picture). Some slide making software is also included.
PC free presentations
Some newer models can present slide shows, images and movies that are in specific formats from a USB drive or memory card plugged directly into the data projector.
Wireless or wired
Current advances in data projector technology include ‘wireless’ models. There is little information available in regards to the effectiveness of these models however information security should always be considered when using wireless connections.
The advantage of wireless is that it is easier to install and there is more flexibility for presenters and positioning of the computer.
There is a delay when using wireless that is particularly a problem for showing video in real time. Wireless enabling devices are available that can convert a standard wired data projector into a wireless model through a USB receiver device (eg LiteShowII from InFocus).
Anti-theft
Vendors promote features that reduce physical and information theft including some of the following: security anchor point, user password, control panel lock and text superimposing.
Portable and fixed
All projectors can be moved or fixed. Models considered portable are generally more compact, lightweight and/ or include a carry-case.
Mounting brackets and extension poles are generally an optional extra even on ‘fixed’ models.
Connectivity
Substantial costs are involved in installing or moving connectivity and power as well as fixing ceiling mounts for a data projector.
Portable options are not always ideal in a classroom setting as safety and security as well as functional issues can arise.
Varying arrangements of connection types are available and are required for different devices/ components (PC input, HD tv, audio etc.)
Remote controls
Generally a remote control is a standard inclusion. In some cases these include features such as a laser pointer however often they are a basic compact model. Advanced remotes are also available as an optional extra for some models.
Software licensing and MOE
Not all data projectors come with software and therefore this section does not apply to all models.
To determine MOE compliance you should identify what default location specific drivers and software install to and whether this can be changed by the installer, if necessary.
Administrative rights may be required to install some drivers and software or to access the LAN (Local Area Network) on MOE computers.
It is important to carefully read software licensing terms as you may be required to remove software from one computer before installing it onto another if moving the data projector from one room to another (eg. “The Software may be used only on a single computer by a single user at any time…”)
Educational applications for a Data projector
The following ideas have been collated from teachers working within Education Queensland.
Good teaching practice and quality learning activities are required to achieve quality learning outcomes.
A data projector can be simply used as a presentation tool however has the potential to enhance all stages of the learning process, as in the following sample activities:
Creating with ICT
Students can use a data projector either on it’s own or in conjunction with an electronic whiteboard for enhancing interactive and collaborative learning in small groups or as a whole class for:
Planning using:
document creation software
mind mapping software
online tools (eg. Web 2.0 planning tools)
electronic whiteboard software
Visual representations or words
Creating assessment items (or components) that:
Are genre specific
Can be shared with others
Are authentic
Can be easily stored and retrieved
Include current data and information
Can be edited by self, peers or teacher
Creating assessment items (or components) using software or Web 2.0 tools to create:
Documents
Productions
3D Content/ games
images
Groups of teachers can collaboratively create planning documents more easily with a data projector
Teachers can create, store and reuse interactive learning experiences using electronic whiteboard software and tools (eg. Flash dice, hundred tables, learning objects) to be viewed through a data projector.
Communicating with ICT
The data projector can be used in small or large group online communication learning experiences, to improve collaboration including chats, forums, blogs, wiki’s and net conferencing so that:
o Students learn from others (eg. other students, parents, experts) locally, nationally and internationally
o Students learn collaboratively with others
The data projector can be used in small or large group online communication learning experiences, to improve collaboration and can be enhanced further with:
· Online communication tools (eg Learning Place tools, web 2.0 tools)
· Image capturing ICT devices (eg. digital still cameras, camcorders and web cam’s)
· Audio capture devices (PC microphones, ipods, MP3 players
The data projector allows a large group of people access to digital media for presentation of information or data (component of a learning experience or presentation).
Some data projector software/ hardware allows for multiple sources to be visible at one time or for a single source to be viewed on multiple screens.
Teachers can share resources with a group of peers using a data projector for Professional development.
Inquiring with ICT
Students can use a data projector either on it’s own or in conjunction with an electronic whiteboard for interactive learning individually, or collaborative learning in small groups or as a whole class when:
o Using learning objects
o Researching on the Internet
o Communicating with experts
Ethics, Issues and ICT
Students and teachers both model responsible use and discuss ethics and safety issues associated with data projectors including those associated with appropriateness relative to audience, electrical safety and tips, and wireless network security.
|
