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drwho
23rd February 2012, 16:27
Hello Folks,

I'm looking for some suggestions for how to solve a small Amiga problem.

I have an Amiga 2000 with an ICD FlickerFree Video (http://www.amiga-hardware.com/showhardware.cgi?HARDID=367) on board connected to a 17" LCD VGA monitor. This works very well, however, there always seems to be a slight "ghosting" of pixels vertically. Kind of like fuzzy scanlines up and down the display in some areas. My apologies if that seems unclear, I will try and post pictures at some point, but, I am hoping there are folks who know what I mean by this.

This problem becomes more of an issue with games, especially non-interlace ones at low resolution. It's not a huge problem, it's just that when playing games, they don't look as crisp as they used to in the old days on a 1084.

I had thought this was an issue with my 2000, but, I don't think it is since I have similar results with the 31Khz port on my A3000T.

I'm looking for a fix for this, if possible. I see these flicker fixer/scan doubler "boxes" on the other bay all the time, like this (http://www.ebay.com/itm/Amiga-Flickerfixer-Scandoubler-A500-A600-A1200-A1000-A2000-A3000-A4000-/200710562137?pt=UK_VintageComputing_RL&hash=item2ebb482159) (hope it's ok to post that here, my apologiesto the mods if not ...). Do these things work, and would that be a better solution to my problem?

Again, my apologies if this is unclear. If needed I will try and take pictures of my screen and post them here

Any help would be great appreciated! :)

Kawazu
23rd February 2012, 16:43
Having the same issue on my 3000T with an LCD, had to change my LCD for an 21" CRT and now everything looks superb.

To bad the 21" is so damn big and heavy.

Maby there are some LCD monitors that can handle it better then others but i have not found any yet :(

drwho
23rd February 2012, 17:07
@Kawazu:
At least I feel better that I am not the only one seeing this issue. This must be a common problem for anyone who uses flicker fixer hardware with an LCD.

I hear you on the CRT, I have moved away from "tubes" in my house and have LCD's for everything. I would rather not go back to one of those if possible.

Ed.D
23rd February 2012, 18:59
I have one of the GBS 8220 converters and whilst it does work it introduces some artefacts of its own. e.g. in an interlaced mode when your mouse pointer moves over an icon it shimmers around its edges, almost like there's some kind of lag when de-interlacing that area of the display.

It's also not as clear as a screen mode which is 'matched' to a proper screen. I think that is because it may be trying to expand the original resolution and add anti-aliasing, it just looks a bit like soft focus.

drwho
23rd February 2012, 19:36
@Ed.d:

Did you just create a custom cable for the 23 pin RGB port on the amiga?

Seems like an inexpensive unit, might be worth it just to try it out.

fitzsteve
23rd February 2012, 19:47
RGB-Scart on LCD TV's seems the best solution to me, and Indivison products seem to work very well :)

Here are a couple of pics of RGB-Scart on my Toshiba 19in LCD TV:

http://i294.photobucket.com/albums/mm105/fitzsteve/IMG_1869.jpg
http://i294.photobucket.com/albums/mm105/fitzsteve/IMG_1868.jpg

drwho
23rd February 2012, 20:57
@fitzsteve:
that looks really good, although, "scart" is something I have never used before. In fact, I don't think I've ever owned a TV that has the connection.

Part of the issue may be the age of the ICD FFv unit. It's ancient, and wasn't exactly a great product when it was new. :)

The A3000T has a similar issue but it's just a tiny bit better.

It's almost like the vertical scan rate is just a little bit off. There is a floppy for the ICD which has a tool that allows you to adjust the scan rates, however, this is of no help when playing games, of course.

rkauer
23rd February 2012, 21:02
Most LCD screens are suited for NTSC resolutions (multiples of 200), not multiples of 256 like PAL resolutions. Vertical banding is a common issue in darker solid colours.

You'll hardly see those if using white or yellow backgrounds.

drwho
23rd February 2012, 21:21
Most LCD screens are suited for NTSC resolutions (multiples of 200), not multiples of 256 like PAL resolutions. Vertical banding is a common issue in darker solid colours.

You'll hardly see those if using white or yellow backgrounds.

Of course, being in the states, I am working with NTSC hardware. I guess there isn't much I can do about this if I understand correctly?

Ed.D
23rd February 2012, 21:28
@Ed.d:

Did you just create a custom cable for the 23 pin RGB port on the amiga?

Seems like an inexpensive unit, might be worth it just to try it out.


I've soldered a 23 pin D-Sub connector to the cable that comes with the unit. Details are in Harrison's thread (I didn't use any resistors):

http://www.amibay.com/showthread.php?t=20468

drwho
23rd February 2012, 21:58
It seems like this unit is a good thing to have around, even if it wouldn't address the problem that I am having.

On a side note, has anyone used or would recommend the ones being sold on the other bay that I linked to at the top of the thread?

I like the black case, and the fact that it's got the 23 pin cable attached already. The seller seems to have great feedback.

Any thoughts?

Harrison
24th February 2012, 01:23
I know we shouldn't price drive, but many of the pre-built units found on ebay, whilst with pre-made cables and in a case, are still just a GBS-8220, so the sellers are adding a huge markup for the privilege of putting it into a case and making a cable. But I suppose it depends what you want and if you don't want the hassle of making it yourself.

Hell_Labs
24th February 2012, 04:58
If I didn't hate paypal/ebay I'd be knocking out those GBS boxes too...

Actually that gives me an idea. Anyone know how much lasercutting costs?