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Looking for Secondhand Video Equipment?
Looking for the Pin Out for a Connector?
Looking for a Video Hire Company?Visit our Friends at Stagelink, who list all sorts of video suppliers. AV Hire Companies Listed By County - Ukslc.org Computer Based Visuals anyone?Again, not complete...
Screen ResolutionsThe most commonly encountered screen resolutions are below, for a full list, have a look at the Screen Resolutions page.
A great representation in easy to understand terminology for screen resolution and how they represent the screen ratios (ie 4:3, 16:9, etc) can be found here at the Wikipedia site. Video StandardsLuminance - 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 System Committee The composite video standard used in the USA, Canada, Mexico and Japan. Uses 525 lines per frame and 29.97 ("30-drop") frames per second. SECAM - SEquentiel Couleur Avec Memoire 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 odd or even lines, is a 'field'. Line 1, 3, 5 etc are scanned in the first field, followed by 2, 4, 6 etc in the second field. Frame - in most video systems two fields are interlaced 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. Recommended ReadingClick here to go to the Recommended Reading topic. To be written:Projectors (LCD v DLP) VGA Splitting and VGA Extending Categories: Video | FAQ
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