NES - Top Row Of Pixels Shifted

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lechu
Posts: 107
Joined: Sat Aug 15, 2015 12:52 am

NES - Top Row Of Pixels Shifted

Post by lechu »

Sorry if I should post this somewhere else.

I have an NES front loader with an old revision of the NESRGB. I've had this issue for a while, but I never really thought anything of it, since using the OSSC I can crop off area and I'm not a hardcore NES fan, until I realized that this might be an issue with this particular console rather than NES's as a whole.

In a lot of games, I've noticed the top few rows of pixels are shifted and wobbling. It's hard to see, but here are some pictures: https://imgur.com/a/kIuBKpO These are from Mega Man 2, Final Fantasy, and Chip and Dale. It's most noticeable on my modern TV, but it can be seen on my PVM as well (but with a few rows hidden under the overscan area).

Is this just one of those console quirks like the bottom dots on a Genesis, or is there something wrong with my particular console?

Thanks in advance.
fernan1234
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Joined: Mon Aug 14, 2017 8:34 pm

Re: NES - Top Row Of Pixels Shifted

Post by fernan1234 »

Looks like that's just NES jitter. SNES also has it.

Wasn't visible/a problem on most CRTs, can be very obvious on flat panels.

There is a dejitter addon for the NESRGB, and I think newer boards have it built in as an option too.
copy
Posts: 232
Joined: Fri Apr 29, 2016 10:38 pm

Re: NES - Top Row Of Pixels Shifted

Post by copy »

Yeah, this is basically normal for the NES. You can see it in a lot of capture videos.

Even with the add-on dejitter board installed on my NESRGB 1.x, I can still see the shifting distortion in the top sometimes. I don't remember the technical explanation, but even though dejitter stabilizes the sync timing, it doesn't eliminate this visual distortion.

This is almost never seen on the SNES because the top pixel rows are usually black.
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Larrs888
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Location: United Kingdom

Re: NES - Top Row Of Pixels Shifted

Post by Larrs888 »

I got a NES RGB (v3) installed in my AV Famicom earlier this year and had the very same question initially after noticing it in Mega Man 2. It's normal console behaviour and those pixels are in the overscan area that you normally wouldn't see on a CRT. Since Mega Man 2 has a nice grid of boxes in the background of the menus I just cropped them off evenly and entered the image (using RT5X).

Out of sight, out of mind ;)
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