The Blue Room Video and Projection FAQ
Looking for Secondhand Video Equipment?
1. You've tried Google and it's friends? No, well stick 'secondhand video equipment' into a search engine and prepare to be amazed at how many results you get. Narrow it down by adding your country, region or nearest large town.
2. e-bay is full of the stuff.
3. Failing the above, here is a list of a few regular dealers in professional video equipment, it's by no means complete and biased towards the UK...
...if you know of any more who regularly have equipment for sale then let us know.
Looking for the Pin Out for a Connector?
Tom Baldwin's Site
Looking for a Video Hire Company?
Visit our Friends at Stagelink, who list all sorts of video suppliers.
Computer Based Visuals anyone?
Again, not complete...
VGA (Video Graphics Array) = 640 x 480
SVGA (Super Video Graphics Array) = 800 x 600
XGA (eXtended Graphics Array) = 1024 x 768
SXGA (Super eXtended Graphics Array) = 1280 x 1024
UXGA (Ultra eXtended Graphics Array) = 1600 X 1200
Luminance - the brightness of a video image. Also known as 'Y'.
Chrominance - the colour of a video image. Usually comprising two signals called 'U' and 'V' (or 'I' and 'Q' in the US).
PAL - Phase Alternating Line
The composite video standard used in the UK and most of Europe. Almost always used as 625 lines per frame and 25 frames per second.
NTSC - National Television Systems Committee
The composite video standard used in the USA, Canada, Mexico and Japan. Uses 525 lines per frame and 30 frames per second.
Composite - Luminance and Chrominance are combined together using PAL, NTSC or SECAM. The process restricts the bandwidth (resolution) of the components. It is easy to add the signals together but difficult to reverse the process. The complete signal is carried on a single wire.
Component - Luminance and Chrominance remain as separate signals. Usually component is taken to mean a YUV signal but RGB is also a component signal. Uses 3 wires.
RGB - a video format where the Red, Green and Blue components of a video image are processed and transmitted separately. Uses 3 wires.
YUV - see Component above.
YC - a video format where the luminance and chrominace signals are handled separately. C is made by mixing the two, U and V, components. Uses 2 wires.
Line - a video picture is made by scanning a scene in both the horizontal and vertical directions at the same time. One scan from side to side is called a 'line'
Field - a complete scan from top to bottom, made up of lots of lines, is a 'field'.
Frame - in most video systems two fields are interleaved to make a 'frame'.
Sync or Syncronising Signal - to keep the scan process in all the interconnected pieces of equipment in step with each other a special signal is tranmitted along with the picture. This is the Sync signal. It can be sent added to one of the video signals or down a separate wire.
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If you have any suggestions for more useful information then please PM me.
This post has been edited by peternewman: 24 August 2006 - 11:28 PM