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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: lurkist on September 29, 2005, 01:21:13 AM
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Are / were there any monitors that displayed hi-res laced native Amiga output without flickering?
Is there a spec that describes this (they never just come out and say it!)
Cheers
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There were monitors like the 2080 that were long persistence. Not much of an improvement over the 1084(s) though. Games would exhibit streaking/ghosting. Basically anything that moved fast. Two steps forward, one step back. Otherwise, AFAIK, you need a flicker fixer.
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I am not sure about this one.....
There was this Phillips monitor i believe back in the day my brother got for his Amiga 1200...and that bad boy would not flicker even on the high res modes!
there might be onfo on which one it was, but i know the beginning years of 1990-1995.... :-D
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I've got an A2024 (http://www.amiga-hardware.com/showhardware.cgi?HARDID=863) that has an integrated flicker fixer, but it's b/w.
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Yup, any LCD TV will do this.
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TV or monitor? My LCD monitor flickers terribly in Hires lace.
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vic20owner wrote:
TV or monitor? My LCD monitor flickers terribly in Hires lace.
Weird... LCD's don't need to be refreshed (a pixel stays lit until told to do otherwise) unlike CRT phosphors that fade out. PAL will always flicker i bit due to its 50Hz nature.
With my Samsung LCD TV/Monitor, with a CD32 connected via the S-video input, Interlace IMHO doesn't flicker more than non-lace, however some 'weird' artifacts (similar to when using a flickerfixer) do appear (ghosting of the mouse pointer when moved). It even did Super Hires Interlace really good, clear text and everything.
But, as anything else, personal opinions and varying mileage with different monitors are important factors here.
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Hmm.. perhaps TVs have a special feature which is to prevent flicker at 50-60hz, perhaps it's scan doubling? I'm able to tune out most of the flicker on my a1200 and lcd flatscreen, but it's still there and fairly obvious in hires lace.
My "Magic VGA" scan doubler will arrive tomorrow. I'll do the a1200 -> s-video hack over the weekend and post the results.
Have you connected your CDTV to a vga box using s-video? If so, how are the results? Any flicker? Color bleeding?
Thanks
-vic20owner
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@vic20owner:
Are you using a scandoubler on your A1200, or does the monitor support 15kHz?
My LCD TV/Monitor has both VGA, SCART, S-video and Composite input, I'm using S-video right now (best available signal from a stock CD32). I guess the TV/Monitor maybe has some sort of flickerfixer on the TV bit.... don't know. All I know is that it won't accept 15kHz input on the VGA connector (complains about it being an 'unsupported mode') whereas Amiga RGB on the SCART works...
-Paul
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An LCD monitor by design is absolutely flicker-free (no, don't call me an idiot yet, read on) since the picture is stored in the pixel matrix, i.e. you are looking at a large memory chip where the bits are shown as colors/different brightness.
During the scan of the sequential analog video input the values are digitized and written to the matrix. This is the big difference to a CRT where the scan is transferred to the tube, lighting a pixel for a very short time, which keeps getting darker until the next scan.
Interlaced video has the problem of separate odd/even fields being transmitted alternatively, so a progressive display like an LCD has to adapt to the signal. There are various methods of doing this, differing in price and quality and some don't do it well - that's why LCD monitors are roughly the same picture quality, but there are large differences in LCD TVs, esp. when it comes to fast horizontally moving objects (marquees etc).
A good LCD TV will flicker fix Amy pretty well, but due to the different methods not every model is suited for this purpose.
So I wouldn't buy any LCD TV without testing it very throughly before, or without refund option.
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Ahh this makes sense. So the flicker will still be there unless the LCD is designed to display interlace without flicker.
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tv signals - pal or ntsc are interlaced. many modern tvs especially lcd ones clean the image up with comb filters etc. lcd tvs also have to convert the image to digital so it is pretty easy to make it noninterlaced.
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A comb filter is for separating RGB components out of composite video - but generally you're right. When it comes to RGB computer video (ie Amiga) some filters may produce artifacts - or even flickering. (E.g. on computer video contrast between neighboring lines can be extreme, bandwidth of the signal is magnitudes higher than on filmed video and so on.)
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right older tvs sent the composite signal right to the video amp after separating sync. on ntsc tvs there is chrominance and luminance with newer tvs the signals are separated cleaned up and sent to separate video amps to drive the display tube. newer tvs work more like monitors.
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God you guys sound just like my old dead pal Larry.... he knew about all that stuff and could explain it to me in real slow easy words.... I sure miss him!! Eat yer freakin green beans, oat meal and exercise boys, because when you kick off there may not be any frontal lobed people left to replace you! I'm serious! I haven't anybody around here to ask serious techy questions because all they know is Windoze and what's in the manual. Do the newer HDTV monitor/TVs display Amiga output fairly well? like if you're doing animations, not games? What about an RGB projector than scans down to 15 hz? Would that work? Because I am down to two monitors for 5 Amigas and I wanna do some animations but I want them to look good on a TV. I have two Supergens and 3 Toasters so I got the hardware, but my display issues are vast! help...