Vital features of business projectors:
¤ Auto-Input: When you switch on your projector after having connected the PC to it, the projector should be able to detect the input signal automatically and start projecting the screen from PC. Alternately, it should also be able to identify if a video source / High Definition (HD) source (component input) is plugged in and project them automatically.
¤ Auto-Keystone Correction: A keystone error is formed when you tilt the projector slightly upwards to project to the screen which is above the viewing angle of the projector. A trapezoidal projector screen image is formed instead of the rectangle projection image that is expected of it. Normally, you need to get to the remote and adjust the keystone error manually. Some projectors allow you to do that by a single touch of a button. But there might be a slight loss in the image quality when this feature is used.
¤ Resolution and Display: Business projectors are either SVGA (800 x 600) or XGA (1024 x 768). Laptops are inherently XGA. So, when projecting from a laptop to an SVGA projector, there would be a quality loss and some shadow formed behind characters. In such cases, if you want a smooth picture, don’t do anything with the projector. Adjust the laptop display to SVGA. XGA Projectors are highly recommended.
The inherent display for projectors is 4:3 (Length by width), but laptops use mostly 16:9 display ratio. There are some projectors which can display 16:9 display ratio output, and that is recommended for laptops.
¤ Lamp Life: The lamp in a business projector is a consumable. It is required to change it every 2000 to 3000 hours. It is quite expensive, so it is better if the lamp prices/lamp is ascertained beforehand. It is also important to note the lamp warranty which is mostly for 3 to 6 months while the projector itself has warranty of 2-3 years.
¤ Cooling Fan (Auto Off mode): The main power for the projectors normally need to be switched off only after the lamp is cooled for a minute or two. This is quite critical for enhancing the lamp life. But most of the users just remove the plug immediately after the presentation. Some projectors allow such auto-off by making the Fan run on saved power for about a minute, not affecting the lamp life. Water cooling method, if available is better and also gives a quieter operation.
¤ Freeze/Shutter: When you are running the presentation by connecting your computer, suddenly you need to refer a price list. But you don’t want everyone to see it on the projector screen. You can freeze the projector output to whatever presentation you are making (temporarily), see the prices, and release the freeze after you come back to the presentation. There is a digital shutter which temporarily blocks the lamp output, and you could write down something on the board to carry the explanation further, delete it, and then release the digital shutter to see the projector output back.
¤ Weight: There are projectors starting from 1 Kg, which are very light weight and easy to carry. But the lamp life of such projectors would be lesser as they generate more heat in a compact environment. If it is going to be fixed projection in a board room, it is better to go with the projectors which are larger and have more cooling fans.
¤ Ceiling Mountable: When the projectors are kept on a ceiling mount, they are essentially inverted upside down. So, the image also needs to be inverted upside down in order to appear straight for the users sitting on the conference hall. Most of the projectors do this, and they also come with a ceiling mounting kit, to fix them on a ceiling. Remember that if the VGA cable is longer than 20-25 meters, there might be a reduction in the quality of images that is displayed in the screen from the PC.
Features that add-value:
¤ Auto Shutter: There are some projectors, which have an auto shutter around the lens so that when the projector is switched on, the shutter opens and when the projector is switched off, the shutter closes automatically. This helps the projector lens not gather dust, which might otherwise be left open.
¤ Screen size/ Throw Lenses: The projectors can generally project images from 30″ Diagonal to 300″ Diagonal. But they can project only certain lengths from certain distances. To get a huge image from a very short distance, a short throw lens is used (This needs to be purchased separately). Similarly, to get a smaller image, from a longer distance, a long throw lens is used.
¤ Optical/Digital Zoom: When the projector is kept at a certain distance from the screen, and the projected image is slightly short of full screen, the optical zoom can be used to make the image slightly bigger. A digital zoom functionality is used to make a particular portion of the projected image appear in full screen so that more details can be seen. But this decreases the clarity of the image.
¤ Auto Focus/ Manual Focus: If the distance from the screen of a projector is changed, then the focus needs to be adjusted manually for a clear image. Some projectors can do it automatically.
¤ Lamp brightness selection mode: Let us accept it. We never need 2000 Lumens of brightness in a small conference room. In such cases, the lamp brightness can be reduced to lamp saver mode to increase the lamp life.
¤ Built-In Audio: Very rarely, the built-in audio might come handy. Especially when the laptop speakers are not audible. Some projectors can give a decent sound output along with image output.
¤ Security: Some projectors offer the Kensington lock or a attachment to chain the projector to keep it from being taken away for physical security of the projectors. Some projectors also prompt the user to enter the password during start-up and only after the password authentication, the computer screen is displayed on the projectors.
¤ Direct projection from USB Stick: Some projectors enable direct projection from USB Stick, instead of having to carry a laptop along with the projector just to show a PPT file. There are also such presenter devices available from third party companies to plug in a USB device and start projecting. The only dis-advantage in this case is, all the files need to be converted in to image format for projecting them through the presenter device or USB stick.
¤ Two VGA Ports: If the projectors support two VGA ports, one of them might be connected to the CPU and the other can be connected to the monitor. This is because, unlike laptops, the monitor cable of the PC directly connects to the projector from the CPU. So, unless one more cable goes back to the computer monitor from the projector, the images might just be visible on the projector screen but not on the PC monitor! Some vendors allow both the VGA ports to be configured manually as input ports, and connect two laptops to switch over between them, during the presentation.
¤ Full Function Remote: Most of the projector functionalities are controlled by a remote control. There are also special remotes which have a laser pointer built in to them and also have a wireless mouse. So, users can use such full function remote control to control some mouse functionalities of the PC like going to the next page in a PPT presentation, for example.
¤ Wireless Projection: Click this link for a detailed article on wireless projection.
You could stay up to date on the various computer networking technologies by subscribing to this blog with your email address in the box that says ‘Get email updates when new articles are published’