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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: pan1k on July 13, 2006, 07:06:02 PM

Title: Question about ScanDoubler and Mediator Video Card
Post by: pan1k on July 13, 2006, 07:06:02 PM
i'm going to be purchasing a Mediator for my A1200 soon. I'd still like my old games to work with my system. Will I need both a scandoubler and a PCI video card (Scandoubler for the games and PCI videocard for workbench) ? I have a pretty sweet 19" Sony Monitor that was given to me that i'd like to put to use soon.
Title: Re: Question about ScanDoubler and Mediator Video Card
Post by: keropi on July 13, 2006, 07:14:04 PM
yes, u will need those 2... you will also need a switch to make the AGA/RTG change...

see here what I did to my machine... http://eab.abime.net/showthread.php?t=24421
Title: Re: Question about ScanDoubler and Mediator Video Card
Post by: pan1k on July 13, 2006, 07:19:22 PM
Ok this is why I am asking these questions. Why would I need a switch? I get that AGA is the the Amiga's built in graphics, RTG is Retargetable Graphics why would I have to switch between the two? Sorry i'm asking these questions, i've never built a towerized amiga before.
Title: Re: Question about ScanDoubler and Mediator Video Card
Post by: x56h34 on July 13, 2006, 07:25:54 PM
Quote

pan1k wrote:
Ok this is why I am asking these questions. Why would I need a switch? I get that AGA is the the Amiga's built in graphics, RTG is Retargetable Graphics why would I have to switch between the two? Sorry i'm asking these questions, i've never built a towerized amiga before.


Voodoo will output RTG display only and Amiga RGB output (or a scan-doubler for that matter) will output the native displays only. If you'd like to view both displays on one monitor, you need some sort of a monitor switcher in order to pull this off, or two monitors.
Title: Re: Question about ScanDoubler and Mediator Video Card
Post by: keropi on July 13, 2006, 07:31:24 PM
it is simple... it is like having 2 graphics cards...
workbench uses the RTG card (in this case the vga on the mediator) as some games that have rtg option.
but if you plan to play whdload games, that "talk" to the amiga hardware directly, they will use AGA only, and there is no way to change that. so, you have your monitor plugged on the pci card, and you start a game that uses AGA, so u need to plug the monitor to the aga output, a scandoubler in this case, to see the game. so if you have a switch you press a button and it switches. if you have a dual input monitor you press it's button, and if you have a zorro based rtg that has a built-in automatic switch (like the picassoII, piccoloSD64) it makes the switch auto.
I hope you get the meaning of all these... :-)
Title: Re: Question about ScanDoubler and Mediator Video Card
Post by: pan1k on July 13, 2006, 08:43:21 PM
Makes perfects sense to me. Thanks for all the replies! Would a Bvision be able to do the switch automagically too?
Title: Re: Question about ScanDoubler and Mediator Video Card
Post by: alexh on July 14, 2006, 12:08:11 AM
Nope. There used to be this thing called an Automon, but they are like rocking horse poo.

If you get a dual input monitor you can switch manually, or perhaps "blank" one output and make it auto switch.

The best solution (in the UK dunno about USA) is to look into getting an LCD Television with VGA and RGB SCART inputs. They have scandoublers built in.
Title: Re: Question about ScanDoubler and Mediator Video Card
Post by: Gav on July 14, 2006, 02:05:01 AM
Yeah it is a pain in the ass all this screen mode stuff but anyways i use a monitor switch box which has a cable  from my voodoo and scandoubler....

It's also a pain when you buy a soundcard and use whdload games which of course switch off workbench.
Cheers
Title: Re: Question about ScanDoubler and Mediator Video Card
Post by: keropi on July 14, 2006, 05:55:09 AM
pain with soundcard? why? I just feed the paula to the line-n of the soundcard and it just works, switching to whdload does not mute it...
Title: Re: Question about ScanDoubler and Mediator Video Card
Post by: Angus on July 14, 2006, 10:51:24 AM
Quote

pan1k wrote:
i'm going to be purchasing a Mediator for my A1200 soon. I'd still like my old games to work with my system. Will I need both a scandoubler and a PCI video card?


Actually no. You need a graphics card (eg Voodoo3) to make the Mediator work at all I believe, but as for games you could simply buy a pci TV card and take the comp signal from the back of your 1200 and put it into the TV card, which would let you either run games in a window on Workbench or fullscreen.

The quality is less than using RGB of course, but if you use a decent quality (and short) cable, I think it gives a pretty good result. Its the method I use.
Title: Re: Question about ScanDoubler and Mediator Video Card
Post by: keropi on July 14, 2006, 11:52:17 AM
oh yeah, the TV-Tuner solution, the poor-man's scandoubler... crap quality though, because you only use the VHS input, plus the BT chipsets of the amiga supported tv tuners are not the best arround...
I wish I could use the phillips SAA71xx based cards, way better in quality...
Title: Re: Question about ScanDoubler and Mediator Video Card
Post by: Angus on July 14, 2006, 01:35:11 PM
Quote

keropi wrote:
oh yeah, the TV-Tuner solution, the poor-man's scandoubler... crap quality though, ...


I think "crap" is a bit harsh, its certainly not great quality but for the price of a TV card on Ebay you could afford to get one and decide if it was acceptable. I think I'm right in saying that external scandoublers don't give perfect colour, so even that maybe a slight compromise.

As I say though, buying a decent quality lead improved the result quite a bit.
Title: Re: Question about ScanDoubler and Mediator Video Card
Post by: keropi on July 14, 2006, 02:40:03 PM
ofcourse you can live with it, but if you compare it against the rgb output on a real amiga monitor, or a scandoubler vga output, then it is crappy... if it was a SVHS output then it would be far better, but vhs is the last in line... I have connected many consoles to the vhs/svhs inputs of my tv-tuner on pc, the vhs is blurry and suffers from color bleeding...
Title: Re: Question about ScanDoubler and Mediator Video Card
Post by: Legerdemain on July 14, 2006, 04:51:27 PM
...ok...

...just to get some things straight here...

1. You should be aware of the fact that there isn't even ONE single scandoubler available for the A1200 which is true 24-bit (not that I am aware of, at least). What does this mean? Well, that there is no way for you to properly display the AGA-screenmodes with the help of a scandoubler for the A1200 (the AGA will look like ECS/OCS and be everything but pretty).

2. S-VHS is not the same thing as S-Video. S-Video connectors do exist on some TV-cards that can be used with the Mediator. Aver TV-Phone is one. I don't see why this input couldn't be used together with an RGB -> S-Video converter. I would try it out myself right now if it hadn't been for me not having that kind of converter at hand at the moment.

3. The sad thing when using the TV-card to display the graphics isn't only that the quality of the picture is 'crap' (well, some could say that it is perfectly decent according to them, but it is still 'crap' and most probably worse than using the computer with an RF-cable connected to a decent TV-set), but also the fact that you most probably will have the update of the screen reduced to 25 or 30 FPS making everything that scrolls around scroll around VERY jerky. What am I trying to say here? Well, that it is very much a WORKING solution, but in the end it all comes down to what you demand from your solution.

4. It is pure hell to get some things to run in fullscreen when using the TV-card solution since once you start an OCS/ECS/AGA application your RTG-screen freezes and there is no way to make the TV-application to automatically realise when this happens and turn the window to fullscreen... so unless there is an delay available such as the once in WHDLoad (or one manually made with a script) it is pretty much impossible to get some things to run in fullscreen with this solution (once again, at least as far as I know). Non-WB-startable applications are out of the question, by the way, since this solution need WB to be running to work.
Title: Re: Question about ScanDoubler and Mediator Video Card
Post by: keropi on July 14, 2006, 06:34:08 PM
color matching and blur/bleeding colors are 2 different things. No matter what sd/ff you have, it will still kick the a$$ of a vhs input.
SVHS and S-Video INPUTS mean the same thing here (Greece) if it means something else there , I don't know...
Also does the rgb output of the a1200 provide the luminance and chrominance signals to create the S-Video signal?
and the jerkyness is a thing I forgot, it is valid and annoying.
On a pc one can use a prog like FLY2000TV to make the tv-card output 2x fps, (50 for PAL, 60 for NTSC) thus giving fluid motion (fly2000tv worked only on SAA71xx chips, but now later versions added BT878 support)
Title: Re: Question about ScanDoubler and Mediator Video Card
Post by: Legerdemain on July 14, 2006, 07:33:58 PM
Quote
color matching and blur/bleeding colors are 2 different things. No matter what sd/ff you have, it will still kick the a$$ of a vhs input. SVHS and S-Video INPUTS mean the same thing here (Greece) if it means something else there , I don't know...


VHS and S-VHS is two different video systems; in other words, two different formats to record and play analogue video. S-Video is short for Separate Video and is a video signal. Its quite a difference, really, and that is valid for every country. But, yes, S-VHS and S-Video is VERY OFTEN confused to be the same thing. So, in short: S-Video, Composite Video, RGB and such... are all analogue video signals... which VHS and S-VHS isn't. So, in all honesty, I don't have a clue as of what you mean with VHS input, sorry.

And, no, a ScanDoubler doesn't necessarily have to produce high quality video output... but, yes, in most cases there will be insanely much better quality of the picture when using a ScanDoubler/Monitor solution than when using a, for example, composite video together with a TV (obviously).


Quote
Also does the rgb output of the a1200 provide the luminance and chrominance signals to create the S-Video signal?


No, it doesn't... but you could still use a RGB -> S-Video converter and get much better quality of the picture than when using composite video (or worse, a RF-connector) as long as the TV-cards drivers support input from the S-Video connector.
Title: Re: Question about ScanDoubler and Mediator Video Card
Post by: keropi on July 14, 2006, 08:03:00 PM
if the rgb port cannot provide luminance and chrominance, then u cannot make an S-VIDEO cable, because this cable constists of these two signals...
and by VHS I mean the AV cable AKA composite AKA the one that has all the picture signals in 1 wire, hence the bleeding and bluring... u know the yellow plug looking like the sound RCA plugs... don't know how to explain better :-D
Title: Re: Question about ScanDoubler and Mediator Video Card
Post by: Legerdemain on July 14, 2006, 08:30:36 PM
@keropi

There are tons of RGB to S-Video converters out there. Fully functional. I am not thinking of a S-Video cable that you put directly on the RGB port, rather a regular RGB-scart which you then convert into S-Video and then plug it into the S-Video connector on the TV-Card.

Not really related to this thread, but if there is one thing I can't understand it must be the lack of RGB in the US (and all other places which doesn't have RGB as a standard). I couldn't live a day without RGB output on all of my gaming consoles (and my Amiga). It is a shame that it isn't a standard all over the world, because it is surperior to all of the other analogue video signals, S-Video included... *SOB*  ...I guess it won't matter that much ahead because other digital variants are kicking in, but up until this point I am rather thankful to have been living in Europe.
Title: Re: Question about ScanDoubler and Mediator Video Card
Post by: keropi on July 14, 2006, 09:25:21 PM
ah, u need some circuicity to make S-VIDEO out of rgb.... all consoles , nes/snes/psx/ps1/ps2/gc/dc/saturn etc, have on their scart cables extra vhs/s-video outputs because they natively produce such signals, you cannot just combine some rgb signals to s-video...
ever wondered why there is no s-video cable for the n64? because nintendo did not make it to output one, so you are only limited to rgb and vhs, leaving only vhs for vga-boxes thus producing crappy quality...  :lol:
and yes, scart rgb should be a standard, I hear on US there is a "component" standar, in some cases better than rgb, but never actually saw a device here taking such a signal...
Title: Re: Question about ScanDoubler and Mediator Video Card
Post by: stopthegop on July 15, 2006, 07:22:36 AM
If you have the room (big "if") then the BEST solution is to just use two monitors.  I have a Sony 19" flatscreen hooked up to my Voodoo card and an Amiga 1084s sitting unobtrusively on a custom built shelf right above it.  I leave the 1084s powered off except for the rare program that needs native screen modes or for troubleshooting.  The only "switching" I have to do is switching on/off the Amiga monitor.  Intuition does the rest.  
Title: Re: Question about ScanDoubler and Mediator Video Card
Post by: Angus on July 16, 2006, 04:30:56 PM
> ...just to get some things straight here...

A couple of points.

I've not had a problem myself with getting non-WHDLoad games fullscreen as luckily they have allowed me to insert a WAIT command before they start. I use this with games like UFO, The Settlers and JetPilot. I wasn't wild about the WHDLoad patch for UFO.

Alan Redhouse told me that the internal scandoublers provided better colour quality than external ones.

My TV card provides a better display on my Belinea monitor than I get on my Amiga monitors or TV, but in fairness they have seen better days. :) Joking apart though, it really isn't a bad display.


........and another thing (edit)

Getting an RGB to S-Video solution is not straightforward. I don't think you'll find anything you can buy to do the job, which leaves fixing it yourself. There is a document on the web that tells you how to convert an A520 modulator to give an S-Video output. I managed to get a professional electronics engineer to take this on as a favour. He followed the steps, and tweaked it around but could not get it to work as described.

In fairness it could have been a different revision of Modulator, but at the end of the day, this solution did not prove to be as easy or as straightforward as advertised.


Title: Re: Question about ScanDoubler and Mediator Video Card
Post by: patrik on July 16, 2006, 05:39:13 PM
@Angus:

Internal scandoublers doesn't sample the analogue RGB signal at the 23-pin video-port as the external ones do, but instead reads the signal digitally by hooking on to the outputs from Alice which goes to the DAC and thus get better image-quality as they do not suffer from any sampling artefacts.

Anyhow, all A1200 scandoublers/flickerfixers are crap as they all skip colours. All internal ones gives 4-bits for the green and blue channel and the red channel is the only one which gets the full 8-bit, so AGA games and such look pretty much like they are a OCS/ECS version. In this aspect, some external ones are better as they give 6-bits per colour channel.

The only scandoublers/flickerfixers which gives proper 24-bit (8-bits for each colour channel) are the DblScan 4000 (http://amiga.resource.cx/exp/search.pl?product=dblscan+4000&company=), the Compserv/Arxon Scandoubler 1/2 (http://amiga.resource.cx/exp/search.pl?product=&company=compserv) and the onboard PicassoIV flickerfixer.

Couple this (http://www.keene.co.uk/cgi-bin/codesearch.pl?RGB2S) or this (http://www.keene.co.uk/cgi-bin/codesearch.pl?RGB2SE) with a regular Amiga RGB Scart cable and you are set.


/Patrik
Title: Re: Question about ScanDoubler and Mediator Video Card
Post by: d0pefish on July 16, 2006, 10:07:55 PM
I used to use a DCE Flickermagic ages ago with my A1200 and I think I can remember some of those nice copper gradients appearing colour banded.

I am now the (very, very lucky) owner of a CompServ Scandoubler II for my A4000 and AGA looks lovely now. :-)

It is a fantastic card - everything looks extremely crisp and sharp. The card itself is huge, it takes up the whole length of the video slot area and rests in the support railings. The S-Video and composite out are useful too.

I have still yet to figure out the best solution for switching between the SDII and my CVPPC; ideally looking for a nice monitor with dual inputs. :-?
Title: Re: Question about ScanDoubler and Mediator Video Card
Post by: Legerdemain on July 16, 2006, 10:40:14 PM
Quote
My TV card provides a better display on my Belinea monitor than I get on my Amiga monitors or TV, but in fairness they have seen better days. :) Joking apart though, it really isn't a bad display.


Every kind of TV/Monitor I have tried that runs RGB nicely have given a much better picture than anything related to TV-Cards running with either composite or RF input... and, even though there might exists TV-Cards that outputs the full 50- or 60Hz on the Amiga, I have yet to see one (and or hear from one having used one that seems to work nicely with the Mediator and its drivers). I just can't be satisified with less than S-Video (preferably RGB) and full 50- or 60Hz update. Frameskipping and an obviously rather blurry picture have never been enough for me. I am simply too picky when it comes to this very matter.

But, in the end, like I said earler... it is really nothing but a matter of what one expects and demands when running this very solution. Surerly there are tons of people that feel satisfied with what is offered.


Quote
Getting an RGB to S-Video solution is not straightforward. I don't think you'll find anything you can buy to do the job, which leaves fixing it yourself.


I was about to point you towards some sites offering a RGB -> S-Video converter, but I now see that Patrik already has done exactly that, so I won't bother.

:lol:
Title: Re: Question about ScanDoubler and Mediator Video Card
Post by: Cefa on July 16, 2006, 11:31:39 PM
You could always make your own rgb to svideo converter
http://www.nexusuk.org/projects/rgb2svid/

It seems pretty basic electronik but the hard part is getting hold of a CXA1645 IC i think they dont make them anymore.

But apparantly that circuit is standart on the PSX (if you have a spare or broken PSX), so you could salvage that chip and use it. Or you could leave the chip in the PSX motherboard and solder the Amiga RGB signal directly to the chip and break the RGB signal from the PSX to the chip. So the pin output from the PSX gives you the Amiga picture.