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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: Snoozy on January 06, 2012, 12:12:11 AM
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Ok, so i have 2 a1200 both 2b revisions, one has been recapped and the other hasn't.
The one that has been recapped has an aca1230 64mb card and has good/very good level of picture quality via a scart connection.
The one that hasn't been recapped has a blizzard 1220 8mb fpu 33mhz and gives an average picture quality via the same scart lead.
Does the recapping give enhanced signal distribution in the mobo and resultant better picture quality? Or is the aca card and more ram helping improve the picture instead?
(My TV is a 40" Samsung LED 8 series)
Edit: Same PSU in both cases
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I'd put money on the new caps improving signal quality (and let us not forget that Amiga's did have variation in output).
-edit- I suppose one of the accel cards could be messing with the ground signal or something too... Why not swap the boards over and see? :)
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Well, the accelerator shouldn't be having an effect on the picture at all, except for some tearing / glitching issues some people have with certain accelerator / motherboard combinations. Capacitors are quite a likely culprit - even if they haven't failed totally in the average quality one, they could still have degraded enough to cause poor signal quality. Or, one might have failed which wasn't critical, but just helped reduce noise or decouble or something. It's also possible that the power supply is causing a funny noise effect - I had that myself using a PicoPSU and cheap laptop charger. Changed to a better quality one and the picture was crystal clear. The original Amiga power supplies are getting old as well, and they also contain lots of capacitors for smoothing the power and eliminating noise.
Edit: Good point Bloodline, I guess different accelerators could be introducing noise in different ways which cause video issues... Would be interesting to swap them over, and the PSUs, and see if it's linked to either.
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I'd put money on the new caps improving signal quality (and let us not forget that Amiga's did have variation in output).
-edit- I suppose one of the accel cards could be messing with the ground signal or something too... Why not swap the boards over and see? :)
I dare not swap my accelerators around at moment whilst everything is running well ;)
If you've seen a couple of my recent threads i have caused havoc to my 1200's by swapping around CF cards, changing over roms and accidentally damaging tracks on circuit boards, trying 4gb CF cards in pcmcia slot (card is now deceased :() I need to keep my 1200 sealed up for a few months :roflmao:
Was just interested to hear if anybody else has noticed this sort of effect..
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Well, the accelerator shouldn't be having an effect on the picture at all, except for some tearing / glitching issues some people have with certain accelerator / motherboard combinations. Capacitors are quite a likely culprit - even if they haven't failed totally in the average quality one, they could still have degraded enough to cause poor signal quality. Or, one might have failed which wasn't critical, but just helped reduce noise or decouble or something. It's also possible that the power supply is causing a funny noise effect - I had that myself using a PicoPSU and cheap laptop charger. Changed to a better quality one and the picture was crystal clear. The original Amiga power supplies are getting old as well, and they also contain lots of capacitors for smoothing the power and eliminating noise.
Edit: Good point Bloodline, I guess different accelerators could be introducing noise in different ways which cause video issues... Would be interesting to swap them over, and the PSUs, and see if it's linked to either.
Hey Daedalus,
I am using the same a1200 PSU in both cases. Do you think the video/scart lead that amiga kit sell is worth upgrading to compared to my standard scart lead?
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Hey Daedalus,
I am using the same a1200 PSU in both cases. Do you think the video/scart lead that amiga kit sell is worth upgrading to compared to my standard scart lead?
If you're using a composite cable (uses the yellow, white and red connectors) then an RGB cable will give you much better results. I'm pretty sure your TV would support RGB SCART, but might be an idea to check before you buy it. But yes, it makes a very big difference indeed compared to the composite type!
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OK so i have taken on people's advice and purchased a scart video lead from amigakit which cost £21 for a 4.8m lead (too long i know but the 1.5m alternative is slightly too short)
So i don't think there is any improvement compared to my previous scart (gold plated) composite lead.
With my new lead from amigakit everything seems more pixelated.
My tv is a Samsung 8 series 40" LED tv - maybe it is too advanced for this lead from amigakit (The TV cost me £1300 2 years ago! :afro:) I thought these leads were optimised for modern tv's.
Is there some option i need to change on my 1200/tv to give a better picture with this lead otherwise i may aswell go back to my old scart composite as it gives a less pixelated picture :(
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OK so i have taken on people's advice and purchased a scart video lead from amigakit which cost £21 for a 4.8m lead (too long i know but the 1.5m alternative is slightly too short)
So i don't think there is any improvement compared to my previous scart (gold plated) composite lead.
With my new lead from amigakit everything seems more pixelated.
My tv is a Samsung 8 series 40" LED tv - maybe it is too advanced for this lead from amigakit (The TV cost me £1300 2 years ago! :afro:) I thought these leads were optimised for modern tv's.
Is there some option i need to change on my 1200/tv to give a better picture with this lead otherwise i may aswell go back to my old scart composite as it gives a less pixelated picture :(
Lol, more pixelated IS better quality :) the aliasing and blending you get from the poor quality signal on a crapy CRT is actually quite pleasing... I was horrified how bad my old games look on a good quality monitor when compared with a crappy old 15" TV
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OK so i have taken on people's advice and purchased a scart video lead from amigakit which cost £21 for a 4.8m lead (too long i know but the 1.5m alternative is slightly too short)
So i don't think there is any improvement compared to my previous scart (gold plated) composite lead.
With my new lead from amigakit everything seems more pixelated.
My tv is a Samsung 8 series 40" LED tv - maybe it is too advanced for this lead from amigakit (The TV cost me £1300 2 years ago! :afro:) I thought these leads were optimised for modern tv's.
Is there some option i need to change on my 1200/tv to give a better picture with this lead otherwise i may aswell go back to my old scart composite as it gives a less pixelated picture :(
Lol, more pixelated IS better quality :) the aliasing and blending you get from the poor quality signal on a crapy CRT is actually quite pleasing... I was horrified how bad my old games look on a good quality monitor when compared with a crappy old 15" TV
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Lol, more pixelated IS better quality :) the aliasing and blending you get from the poor quality signal on a crapy CRT is actually quite pleasing... I was horrified how bad my old games look on a good quality monitor when compared with a crappy old 15" TV
Ok thanks bloodline, so what's the point of buying these scart video leads (optimised for new tv) if they give a more pixelated picture? Maybe it gives more detail but unlike hd, this detail is worse.
Its not clear to me why ppl buy these scart video leads and then rave about them
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Ok thanks bloodline, so what's the point of buying these scart video leads (optimised for new tv) if they give a more pixelated picture? Maybe it gives more detail but unlike hd, this detail is worse.
Its not clear to me why ppl buy these scart video leads and then rave about them
As resolutions get higher, you want the pixels to be sharper... But many emulators (WinUAE for example) offer PAL/NTSC, CRT and even scanline emulation to try and more accurately recreate that "authentic experience"(tm) :)
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Amigakit fixed/recapped A1200 mobo here with Amigakit-scart cable and picture has never been so good on my miggy on my tube-tv :)
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Amigakit fixed/recapped A1200 mobo here with Amigakit-scart cable and picture has never been so good on my miggy on my tube-tv :)
Ahh I think tube tv is the key here, I don't think led tv and amiga go so well together.
Just goes to show that throwing money at the problem doesn't really help!l
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Well a CRT TV certainly is a big difference here (Man I wish I had a CRT HDTV, but those beasts are very rare these days!), but as Bloodline pointed out, the fact that you can see the pixels where they were blurred before is a sign of a much cleaner signal - it's closer to the "true" output of the Amiga. Maybe there are some settings on the TV for upscaling that might help, but when I'm on a flat panel TV I still prefer the sharp, clean RGB look to the blurry composite with washed-out colours... Horses for courses though, if you prefer the look of the old cable, you should be able to resell your cable without losing much money...
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Any retro system and LCD/Plasma TV's don't mix too well. Even when setting the pictures to 4:3 aspect you can still see that the picture isn't perfect. I have an old Sony CRT that is awesome for playing the old systems, including Amiga, on and the picture is perfect.
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I've been using proper monitors/LCDs for so long now that when I see te Amiga output on a proper 15" CRT I think it looks fuzzy... Even though it does look "better"...
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How about this?
http://www.ebay.co.uk/itm/Toshiba-42WH46-42-CRT-Television-/120839607036?pt=UK_AudioTVElectronics_Video_Televisions&hash=item1c229a12fc
Would that be the biggest and optimum crt display?
I think i would prefer Samsung/Sony to Toshiba...I haven't got enough room for a tv this size until i buy a new house :)
Is anybody using a 32 inch or larger lcd tv with a video scart lead without pixelation?
Edit: And i don't think using 20 inch monitors/lcd tv is the way forwards...I want a decent sized tv with surround sound for my 1200!
Maybe i still have an Xbox 360 display screen mindset and am asking too much from the old technology of the 1200??
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Heck, even on my old 1084 back in the day, things looked strangely sharp compared to my friends who were generally running their amiga off a TV. The ones with 500s and 600s anyways.
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Ok thanks bloodline, so what's the point of buying these scart video leads (optimised for new tv) if they give a more pixelated picture? Maybe it gives more detail but unlike hd, this detail is worse.
Its not clear to me why ppl buy these scart video leads and then rave about them
It depends on the upscaler in the tv. With a composite cable you're dropping detail and then the upscaler will generate new detail. With RGB you're just generating new detail.
Some TV's can achieve a similar effect to 2xsai on the right
http://segaretro.org/images/5/5c/2xsai.png
Others just double the pixels and it looks like the picture on the left.
You could sit further away.
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It depends on the upscaler in the tv. With a composite cable you're dropping detail and then the upscaler will generate new detail. With RGB you're just generating new detail.
Some TV's can achieve a similar effect to 2xsai on the right
http://segaretro.org/images/5/5c/2xsai.png
Others just double the pixels and it looks like the picture on the left.
You could sit further away.
That would mean moving my sofa :)
I think you've hit the nail on the head there psxphill, my samsung led tv looks like the image on the left :rolleyes:
Maybe a combination of the tv being slightly big and me sitting fairly close (2m) away from it :) so i see the pixels and it reminds me of a commodore 64.
How do we achieve the picture on the right which the amiga is properly capable of, does the tv have to have a built in upscaler or is that something to buy separately? I've heard about indivisions but i thought that was to modify frequency settings of tv..
In the meantime i am using 4:3 scaling on my tv and it looks like something has swiped 15% of my screen at either side and replaced with black bars :(
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As part of my professional degree I did some research on the suitability of using CRT's for the purpose of displaying eye sight test charts. This was before LCD's. One of the things I learned is that each pixel on a CRT does not have a square wave luminance distribution. In other words the pixel was brightest in the centre and gradually dimmed out towards the periphery. It mean that light from one pixel blended over the top of the light from an adjacent pixel. This is what made graphic seems smoother on CRT's and less pixellated(but also made CRT's of the time unsuitable for eye sight test charts!)