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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: Imerion on August 17, 2003, 09:37:02 PM

Title: Is it possible to use a high-res screenmode on a pal tv without flickering and without flickerfixer?
Post by: Imerion on August 17, 2003, 09:37:02 PM
Is it possible to use a high-res screenmode on a pal tv without flickering and without flickerfixer? I have an A1200 030-50 10 mb ram and OS 3.0. Please tell me if this is possible.
Title: Re: Is it possible to use a high-res screenmode on a pal tv without flickering and wi
Post by: KennyR on August 17, 2003, 09:38:03 PM
It's not. It's a limitation of the TV.
Title: Re: Is it possible to use a high-res screenmode on a pal tv without flickering and wi
Post by: GPT on August 17, 2003, 09:40:29 PM
Maybe on a pal monitor that has ben modified a bit but not on a tv.
Title: Re: Is it possible to use a high-res screenmode on a pal tv without flickering and wi
Post by: Ilwrath on August 17, 2003, 11:24:40 PM
Quote
Is it possible to use a high-res screenmode on a pal tv without flickering and without flickerfixer?


HiRes?  Sure...  640x256 is considered "HiRes" though.

Interlaced (640x512), which is probably what you are meaning, will flash/flicker, though.  Hardware design.  The best you can do is try to pick low-contrast colors for your workbench.  Dark blue, with a mid-blue text doesn't flicker too bad, but if it's not a perfect picture on a TV, it may be very hard to read, as not enough contrast.......  Experimenting with colors is your only hope, unless you want to buy it a flicker-free monitor. (not 1084 series -- the 1950/60 series)
Title: Re: Is it possible to use a high-res screenmode on a pal tv without flickering and wi
Post by: Kent on August 17, 2003, 11:40:08 PM
It takes a piece of hardware but you can get some of them dirt cheap.  Grab a set of polarized sunglasses and use them when in interlaced mode.  Viola... no more flicker.  If it still bothers you, reduce the contrast and increase the brightness.

:pint:
Title: Re: Is it possible to use a high-res screenmode on a pal tv without flickering and wi
Post by: iamaboringperson on August 18, 2003, 12:47:52 AM
Quote
Please tell me if this is possible.
Yep, it's possible, just select 'hi-res' :-)

Or better yet, buy a graphics card, and decent monitor. :lol:
Title: Re: Is it possible to use a high-res screenmode on a pal tv without flickering and wi
Post by: Karlos on August 18, 2003, 12:50:02 AM
Sure. Get a 100Hz Sony widescreen TV. Those things essentially have flicker fixing hardware built in and run at 100Hz vertical refresh. Any PAL signal they show tends to look nice and flickerless :-)

Not as cheap as the sunglasses or a flickerfixer / monitor combo mind you :-)
Title: Re: Is it possible to use a high-res screenmode on a pal tv without flickering and wi
Post by: AmigaHeretic on August 18, 2003, 12:53:01 AM
I use to use a little program called MagicTV.  It can be found on aminet here:

http://wuarchive.wustl.edu/~aminet/util/wb/magictv2.lha (http://wuarchive.wustl.edu/~aminet/util/wb/magictv2.lha)

It only works on 16 color screens or lower though and requires AGA.  It works great if you want a Hi-Res Workbench on your TV or 15khz monitor.

AmigaGuy
Title: Re: Is it possible to use a high-res screenmode on a pal tv without flickering and wi
Post by: Karlos on August 18, 2003, 12:56:20 AM
Quote

Ilwrath wrote:
...The best you can do is try to pick low-contrast colors for your workbench.  Dark blue, with a mid-blue text doesn't flicker too bad, but if it's not a perfect picture on a TV, it may be very hard to read, as not enough contrast.......  

Actually, there was a patch available a few years ago called 'MagicTV'. If I recall correctly, it uses two sets of bitplanes (thereby restricting AGA systems to 16 colours) and does some custom chip trickery to help eliminate the flicker.

I used it for a while before getting my gfx card and it was very effective at reducing the flickering on both my TV and 1084.

The author stopped developing it after a while, but you can probably still find it on aminet.
Title: Re: Is it possible to use a high-res screenmode on a pal tv without flickering and wi
Post by: Karlos on August 18, 2003, 12:57:14 AM
@Amigaguy

:lol: you beat me to it :-)

-edit-

It had the rather cool side effect that text etc appeared a bit antialiased too. It probably wasn't but it used to look that way on my system.
Title: Re: Is it possible to use a high-res screenmode on a pal tv without flickering and wi
Post by: AmigaHeretic on August 18, 2003, 12:58:22 AM
You remeber that program too?  You must be old like me   :lol:  :lol:  :lol:
Title: Re: Is it possible to use a high-res screenmode on a pal tv without flickering and wi
Post by: Karlos on August 18, 2003, 01:00:39 AM
Well, I was recently accused of becoming an old fart :-D
Title: Re: Is it possible to use a high-res screenmode on a pal tv without flickering and wi
Post by: leirbag28 on August 18, 2003, 02:36:57 AM
Oh Boy Oh Boy, some of yu don't get out much.......Yes  it is possible to at least minimize Flickering in PAL Hires Interlaced......one of the reasons the screen flickers is because of those one pixel thin black lines around the borders of windows and buttons and gadgets wich contrast greatly against the one pixel thick white lines........ Solution?  get Visual Prefs from Aminet...and MUI....whith visual prefs.....double the thickness of the lines and change any lines that are black on the Title bars, butttons gadgets, window borders... to dark grey and the white lines to a very light grey ( and of course like I said make them double the thickness) and you will be surprised how much less it flickers! totally usable!...now do the same thing to as many Public screens as possible and those will flicker less as well.  
 Now the colors dont have to be Dark grey and Light grey....you can also use....lets say.....dark blue for the shadow and  very light blue for the shine........ trust me my workbench looks nice and flickerless and actually has about as little flicker as a PC connected to a TV with a flickerFixer. Also Ive noticed PAL always flickers much more than NTSC.
Title: Re: Is it possible to use a high-res screenmode on a pal tv without flickering and wi
Post by: AmigaHeretic on August 18, 2003, 02:42:38 AM
Quote
Also Ive noticed PAL always flickers much more than NTSC.


I think it has to do with the refresh rate.  NTSC is 60hz and PAL is only 50hz...I believe.

AmigaGuy
Title: Re: Is it possible to use a high-res screenmode on a pal tv without flickering and wi
Post by: leirbag28 on August 18, 2003, 02:44:15 AM
oops!  I forgot to mention...on top of Everything I just said.....if you want even less flickering....add a genlock (I guess a PAL one for you) like the SuperGen SX and click the notch filter.....it adds some anti aliasing so it now might look a little blurry....so I definitely recommend using bigger and thicker fonts like FuturaB 12 or Workbench 12...................I use my Amiga on an NTSC S-Video TV  full time! and its excellent!
Title: Re: Is it possible to use a high-res screenmode on a pal tv without flickering and wi
Post by: iamaboringperson on August 18, 2003, 02:54:09 AM
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... greatly against the one pixel thick white lines........ Solution? get ...
a high resolution monitor and GFX card :-P
Sorry, I can't help it when people still want to use such old crappy technology. I'll try to behave in the future, honetly I will. :crazy:
Title: Re: Is it possible to use a high-res screenmode on a pal tv without flickering and wi
Post by: Imerion on August 18, 2003, 10:47:55 PM
Ok then. That program helped a little. It would´ve been nice to see the ham version of it. However, Ill get a flickerfixer...
Title: Re: Is it possible to use a high-res screenmode on a pal tv without flickering and wi
Post by: Ilwrath on August 19, 2003, 12:25:09 AM
Quote
You remeber that program too? You must be old like me


Yeah, I'm old enough to remember it, too...  Of course, I also remembered it didn't do me any more good than a nice low-contrast palatte did, plus it made stuff harder to read, IMHO.  ;-)

I stand by my advice, though, perhaps the sunglasses are also helpful.  :-D
Title: Re: Is it possible to use a high-res screenmode on a pal tv without flickering and wi
Post by: Khephren on August 20, 2003, 11:08:10 AM
There was a patch years ago that ran PAL resolution in NTSC refresh. It was pretty stable, combined with editting the gadget widths/colours as above, and I got a pretty stable WB- without having to resort to 16colour. Your TV had to support both PAL and NTSC though.
Title: Re: Is it possible to use a high-res screenmode on a pal tv without flickering and wi
Post by: vortexau on August 20, 2003, 03:57:33 PM
The original question concerned pal tv sets and as Karlos said, the 100Hz will do this because they use double-buffering like a Flicker-Fixer does!

I recall that Lowe and other German sets had models with this feature.

Standard tv sets use a 50Hz refresh rate that allows only HALF the scan-lines to be written each go. Interlacing allows the between scan-lines to be written.

clariSSA was an Amiga animation application that allowed animation-frames to vary at EACH half-frame, and thus produced SMOOTH movement at 640x512/640x400 formats.
Title: Re: Is it possible to use a high-res screenmode on a pal tv without flickering and wi
Post by: Varthall on August 20, 2003, 04:12:28 PM
Quote

Imerion wrote:
Is it possible to use a high-res screenmode on a pal tv without flickering and without flickerfixer? I have an A1200 030-50 10 mb ram and OS 3.0. Please tell me if this is possible.

Ah, a flicker-free 640x512 screen on my 1084S, that
has been my dream for many years. Using the
euro36 driver the flicker was much more acceptable( it won't work on a normal TV set, btw).
I kept using an interlaced screen until a summer, when I had some type of light epilepsy attack, or this is what I think it was. At that time, after one week I haven't touched my Amiga, I saw some sort of flashes appear in front of me, even if it was daytime and the people around me didn't noticed any flash. I was quite surprised. After this  I decided to borrow a VGA adaptor and to buy an expensive 17" vga monitor. A wise choice, as I never ever had this type of problems again.

Varthall
Title: Re: Is it possible to use a high-res screenmode on a pal tv without flickering and wi
Post by: minator on August 20, 2003, 04:48:36 PM
The irony of all this is that interlacing was originally invented to *reduce* flicker!

I used to use interlaced mode but only using low brightness and very low contrast.

If you want to sit in front of a computer for a long time get a monitor which can handle 85Hz.
Alternately get an LCD screen which doesn't flicker at all (at least not noticably) ...but they do effect your eyes.

Also don't use fluorescent lights as they can interact with the screen (TV and monitors) and cause yet more flicker...
Title: Re: Is it possible to use a high-res screenmode on a pal tv without flickering and wi
Post by: DanDude on August 20, 2003, 06:05:27 PM
Hi-res interlace will always flicker on a TV.  However, there are tricks that you could reduce it.

1. use related colors and no thin horizontal black & white lines
2. turn down your contrast on your TV
3. if you are familiar with art programs and you use graphics that flicker in your background, you can reduce the sharpness.  Reducing sharpness allows other colors to blend in a little and help reduce the flicker like a slightly out-of-focus camera.

To eliminate the flicker, simply select a screenmode that does not have the interlace feature.  
Title: Re: Is it possible to use a high-res screenmode on a pal tv without flickering and wi
Post by: Dan on August 20, 2003, 08:07:54 PM
Quote

minator wrote:
If you want to sit in front of a computer for a long time get a monitor which can handle 85Hz.
Alternately get an LCD screen which doesn't flicker at all (at least not noticably) ...but they do effect your eyes.

Yup, no flicker on an LCD-tv either, I have tried with an handheld Casio.
MagicTV worked fine on CRTs good enough for DOpus but not for reading or editing text.
Title: Re: Is it possible to use a high-res screenmode on a pal tv without flickering and wi
Post by: Dan on August 20, 2003, 08:10:59 PM
Quote

Khephren wrote:
There was a patch years ago that ran PAL resolution in NTSC refresh. It was pretty stable, combined with editting the gadget widths/colours as above, and I got a pretty stable WB- without having to resort to 16colour. Your TV had to support both PAL and NTSC though.

Interesting, how did the tv identify it as PAL or NTSC?
What was the name of it?
Title: Re: Is it possible to use a high-res screenmode on a pal tv without flickering and wi
Post by: KennyR on August 20, 2003, 08:14:57 PM
That's because LCDs don't have a refresh signal like CRT. Trouble is, one is likely to cost as much as a SVGA monitor and graphics card together.
Title: Re: Is it possible to use a high-res screenmode on a pal tv without flickering and wi
Post by: Dan on August 20, 2003, 08:29:42 PM
Quote

KennyR wrote:
That's because LCDs don't have a refresh signal like CRT. Trouble is, one is likely to cost as much as a SVGA monitor and graphics card together.

I know.
Couldn´t read much at a 4 inch screen anyway.