NEW PAGE – UNDER CONSTRUCTION – MARCH 23 2020
Connecting from a laptop or computer to a projector
This is a standard-definition analogue display output, that was the standard on laptops and Windows computers until around 2015.
Maximum cable length: up to around 30 metres
Pros:Simple signal, usually fairly reliable
Cons: Not great quality over long distances
Common problems: If one of the pins is bent / damaged, the display can appear discoloured. Check the connections are tight and no pins are bent.
(‘High Definition Multimedia Interface’)
Maximum cable length: only around 10 metres
Pros: Great quality (when it works)
Cons: The higher the resolution you’re trying to display, the better quality cable you need.
High resolution over long lengths can suffer with dropouts / digital distortion.
See ‘Boosting the Cable Length’ below for information on how to send high-quality video over long distances.
If you connect the computer to the projector before turning the computer on, it’s likely the computer will detect the projector and automatically switch it’s output accordingly.
If you get no display on the projector after connecting everything together, you may need to activate the computers’ VGA or HDMI output.
ILLUSTRATION – VGA OUTPUT and HDMI OUTPUT on laptop
Windows – VGA output:
On modern Windows laptops, the projector / additional monitor screen outputs can be activated by holding the Windows key (bottom left on keyboard) and pressing the P key (for Projection).
On older laptops, this can either be via the Control Panel, or the output options can be activated one-by-one, by pressing the FN Function key (coloured blue, bottom left of keyboard) in combination with the display function key (sometimes F8 – look for the blue monitor icon on the function keys).
The output combinations are usually;
1) Laptop monitor screen only
2) VGA output only
3) Laptop monitor screen and VGA output (‘extended’)
PHOTO – LAPTOP CONNECTED TO PROJECTOR
Boosting the Cable Length
HDMI video can be sent down a Cat5 / Cat6 network cable over very long distances (up to 50m).
A balun box is required at each end to convert between an HDMI connection and a network connection. These are very often powered interfaces, as they boost the connection strength, and have active circuitry to make the conversion. It’s worth getting the best quality conversion equipment that you can, because the cheaper versions can’t deal with very high resolutions, and you may have to reduce the quality of your video output (from the computer) to make it work.