pm@tcom.stc.co.uk (Peter Mitchell) (05/02/89)
I do not understand why people think that connecting a Multysync monitor to their Amiga will solve the Interlace flicker problems! The interlace flicker problem can be solved by using a flicker fixer in conjunction with a Multisync monitor. A Multisync monitor differs from conventional monitors in that it can synchronise itself to different scan rates for example my PAL Amiga will refresh the screen once every 50 ms which is fine for non interlaced displays. However to display in high resolution ie 640(320)*512 (PAL Amiga) one either has to display the screen in the Interlaced mode, or to increase the scan rate of the display. A Multisync monitor is capable of synchronising to to different display scan rates (within its design specification) and so will be capable of displaying a 640*512 screen in non interlace mode if the scan rate is high enough. The standard Amiga will only display at the standard scan rate i.e it will not increase its scan rate for very high resolution (a pitty! - this would be a nice feature for the new chip set to have a higher scan rate as a software controlable option so keeping compatibility with the standard Amiga, but allowing people with access to a Multisync monitor to use the very high resolutions without the resulting flicker problems). I have had some experience of using the NEC Mutisync II with an Acorn Archimedes. To those of you living in America who may have not come across the Archimedes I will explain. The Archimedes is based on a custom RISC processor - the VL86C010 which rruns at 8MHZ and delivers 4 Mips (is is very fast!). It has 8 channels of stereo sound. The position of each channel is software controlable - i.e you can position it in space. Graphics resolutions are 640*256 (50Hz scan rate) 16 colours max from 4096. 320*256 (50HZ scan rate) 16 colours max from 4096. 640*256 (50Hz scan rate) 256 colours - hardware controled so no palette control. These modes are displayable in interlace or non interlace. 320*512 (75Hz scan rate) 16 colours max from 4096. 640*512 (75Hz scan rate) 16 colours max from 4096. 640*512 is suposed to be available but I could not access it for some reason. 1024*916 - very high resolution monochrome. Other display resolutions are available , but these are mainly to retain downwards compatibilty with the older BBC micro , and these are fake modes. I could not afford to buy myself an Archimedes so I bought an Amiga instead. I discovered using this system that the NEC multisync II does not perform very well in Interlaced mode - i.e you get super flicker!, but it is superb for displaying non interlaced high resolution displays. The Archimedes as standard came with a non multysync monitor as standard made by the same company that made the old A1048 for the Amiga - I think that Philips make it as I have seen these monitors with the Philips brand name on them (I am comparing the NEC to the A1048 equivalent). The NEC monitor suffers from far less reflection (less glare) and has a higher colour intensity resolutiun i.e I would switch the colour palette to display the darkest possible display in a particular colour. On the A1048 equivalent you get a blank display, but on the NEC monitor you get the correct colour display. Basicly what I have been trying to say is that a Multisync monitor will only give you a flicker free display if you can make use of a higher scan rate for the high resolution, instead of using an Interlaced display. The Amiga can not do this without using a flicker fixer.
addison@pollux.usc.edu (Richard Addison) (05/28/89)
In article <1540@bute.tcom.stc.co.uk> Peter Mitchell <pm@stc.UUCP> writes: >I do not understand why people think that connecting a Multysync monitor to >their Amiga will solve the Interlace flicker problems! : >The Archimedes is based on a custom RISC processor - the VL86C010 which rruns >at 8MHZ and delivers 4 Mips (is is very fast!). : >I could not afford to buy myself an Archimedes so I bought an Amiga instead. : >Basicly what I have been trying to say is that a Multisync monitor will only >give you a flicker free display if you can make use of a higher scan rate for >the high resolution, instead of using an Interlaced display. The Amiga can >not do this without using a flicker fixer. Well, my Mitsubishi Diamond Scan does fairly well at reducing flicker because it uses phosphors with longer persistence than some of the more common monitors around. And if your in the market, you can get some realy huge multi-synchronous monitors from them. (#include <std.disclaimer>). Just how much is the Archimedes selling for? Richard Addison "Oh gee, I guess I am in interlace. I can hardly tell."