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Videomaster

290 bytes added, 16:26, 3 September 2017
/* Quality */
On a modern flat screen LCD television the image quality from the Videomaster is worse than the SCART cables you can buy and worse than a native green screen or colour monitor. (This is using a composite to SCART cable).
Mode 0 is fine, mode 1 is useable, but mode 2 is hard to read. This is down to ghosting in the image. With the yellow on blue the ghosting is black. I (arnoldemu) have seen similar when using the SCART output from a KC Compact on a television . I believe the modern televisions are much less tolerant, so it may be that the signals are not acceptable to the modern TV.
The colour reproduction is good although bright white is a little dull for me. My television also has trouble with bright green in that there is visible moving dot crawl around the edges. There is also some noticeable banding between main display and border when the border colour is different from the main area.
Like the SCART, register 3 scrolling can be used (use values 5/6 for hsync length - any lower and the picture loses sync), and like the SCART if you try to use lower hsync lengths and if the border is not black then the main display will become darker.
It has also happened that when I program the television looses sync so that the television can't accept it and when you then re-sync program it back to the default the picture is black and white with noticeable dot crawl all over it. I don't see this with a SCART cable.
I believe On a Sony Trinitron 14" CRT television the problems image is much much better. There is much less ghosting and the image is brighter. Mode 0 is good, mode 1 is fine and mode 2 is readable depending on the colour choices. If I am seeing are down set mode 2, set the background to black and the higher Rtext to bright white I see multicolours moving through the text but it is still readable. The trinitron television accepts shorter hsync lengths,Gbut at 4,B voltage output from the image changes colour with the Videomaster . Restoring the hsync length doesn't work, it remains at the changed colour and using a composite I need to SCARTpower the computer on/off to get the colours back. For some inks the text appears thinner, for other inks it appears fatter. In terms of image quality with colours, green is best, then red then blue.
Unfortunately NOTE: * I am unable don't have other CRTs or flatscreens to compare this with Amstrad's modulatorit on, so I may have been unlucky.
On * I am still investigating how to get a Sony Trinitron 14" CRT television the image is much better. There is much less ghosting and picture out of the image is brighter. Mode 2 is Videomaster because I still hard to read, mode 1 is fine, mode 0 is fine. If I set mode 2, set the background to black and the text to bright white I see multicolours moving through the text but believe it's readable. The television accepts shorter hsync lengths, but at 4, the image changes colour. Restoring the hsync length doesn't work and I need to power the computer on/off. For some inks the text appears thinner, for other inks it appears fatter. In terms of image quality with colours, green is best, then red then bluepossible.
NOTE: * Unfortunately I am unable to compare this with Amstrad's modulator which it claims to be superior to.  * The video master has adjustable variable resistors which may improve this the picture and using a correct composite cable is likely to improve it too. I will get some more technical help and update this.
== Technical ==
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