Problem with image in certain modes

Par vanhiavvi

Supporter (13)

Portrait de vanhiavvi

19-08-2018, 11:54

Hi:

Not sure if it's the right place for this question.

I'm using a MSX2+ with audio video cables and in certain modes it looks good, while in others (with higher resolutions) the pixels have like a shadow, so with small letters it's complicated even to read.

Now I've noticed that with certain games (like Bubble Bobble) the image becomes black and white and it loses pixels. Why could that happen, and especially, how could I fix it?

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Par mohai

Paragon (1031)

Portrait de mohai

30-08-2018, 16:21

Composite video, not RGB, is very low image quality, as signals from video chip modulated and mixed into 1 single signal. That is the reason why you can see pixels flickering or with shadows or color spill.
If you are getting black and white in some modes, maybe it is because of bad modulator and/or bad cable or a not-so-compatible monitor.
Try 50 hz and 60 hz to test.
A good try is to check (and maybe replace) capacitors or other components in the modulator board.

Par vanhiavvi

Supporter (13)

Portrait de vanhiavvi

01-09-2018, 07:09

Thanks, Mohal.

Is there any suggestion regarding the right cable to use? With different hz I think it goes much worse.

BTW, it's working on a Samsung TV.

PD: Not sure what the modulator is

Par sd_snatcher

Prophet (3675)

Portrait de sd_snatcher

02-09-2018, 11:51

What MSX2+ model are you using?

Par meits

Scribe (6572)

Portrait de meits

02-09-2018, 12:01

Are you using flatscreen or old fashioned crt?

Par vanhiavvi

Supporter (13)

Portrait de vanhiavvi

08-09-2018, 13:24

Flatscreen.

Msx2+ Sony HB-F1XDJ.

Thanks!

Par vanhiavvi

Supporter (13)

Portrait de vanhiavvi

08-09-2018, 16:07

Could the V9990 fix anything? Seems an expensive solution (if it's a solution...)

Par Poltergeist

Champion (280)

Portrait de Poltergeist

08-09-2018, 16:23

No, it would not. V9990 is not a replacement for the V9958 in your MSX2+, but an addition. So, using screen 6 or 7 (or screen 0 with width 80) would still use the build-in video display processor.

Par Grauw

Ascended (10821)

Portrait de Grauw

08-09-2018, 17:26

Use a RGB / SCART connection. Composite video picture quality is horrendous.

European TVs will have a SCART input so all you need is the right cable. For TVs outside of Europe you’ll need to get a SCART to HDMI converter as well, these aren’t terribly expensive (€10-€30) and offer adequate results (the EU TVs essentially have this built in).

For the best image quality you want a more expensive SCART to HDMI converter such as the OSSC or the FrameMeister. These will give you really sharp pixels, nice colours and no deinterlacing artifacts, and the OSSC also introduces zero latency. But they’re not cheap, upwards of €200.

Par meits

Scribe (6572)

Portrait de meits

08-09-2018, 20:52

On a flat screen composite is really not an option. a small crt screen could be "acceptable". RGB is really the only output you should pay attention to.
There are several rgb (scart) to hdmi converters, but not all of them are as good a you might hope. I use some of these in case I need to use a scartless flatscreen: Available for several prices in several shops..
The screen to the left is sending the RGB from a Sony HB-F1XDJ to a IIyama LCD monitor's HDMI inlet. I think it is very acceptable.

Par vanhiavvi

Supporter (13)

Portrait de vanhiavvi

09-09-2018, 21:00

Thank you. I'll take a look into it and I'll let you know how it works!