Please help me get the blackest blacks

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After setting my RPi2 to display full rgb, which I know my tv can handle, I’m not certain that I have edited the config.txt correctly as I’m still not seeing blacks the way I would expect. It’s most noticeable when there are titles on movies, a clear black screen will lift a few shades to a dark grey until the next title appears which causes the rest of the screen to go dark. This also happens when there are darker scenes in movies.

I have searched the forums and made sure my config.txt has a pixel_encoding value of 2 as per this post

http://forums.plex.tv/post/quote/94334/Comment_551082

Can someone please help me set this up so I can see the blackest blacks at all times.

Thanks********

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In case it helps, this is the part of my config.txt I’ve edited to enable full rgb


# Uncomment for DVI monitor
# hdmi_drive=1
hdmi_pixel_encoding=2

This forum software is rubbish by the way

3

I think you have done all you can within the scope of Rasplex.

Also bear in mind the hardware limitations of the RPi, it is never going to be as good as a Mac or PC.

Regards

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@NedtheNerd said:
I think you have done all you can within the scope of Rasplex.

Also bear in mind the hardware limitations of the RPi, it is never going to be as good as a Mac or PC.

Regards

That’s a shame, I’m loving Rasplex and this is the only grumble I’ve got with it.

@chenks said:
are you sure it’s not your TV actually causing this?
all modern TV’s have this nasty “energy saving” features that cause the screen to dim or brighten depending what is being displayed - and on mine it’s always most noticeable during end credits with white text on black background.

my samsung doesn’t allow me to completely disable it, so i’ve had to tweak settings to make it the least noticeable, but it’s still there.

might be worth checking.

I’m pretty sure it’s not the TV, I did go and check the energy settings and there was nothing out of the ordinary there. If I watch the same movie via the playstation the blacks stay a constant shade. I guess it must be a limitation of the RPi2

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@Stewie Griffin said:

Not a limitation of the RPi, have you checked all of the picture enhancement features of your TV, first comment in 3 years of this ‘issue’.

Regards

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@Stewie Griffin said:
I’m pretty sure it’s not the TV, I did go and check the energy settings and there was nothing out of the ordinary there. If I watch the same movie via the playstation the blacks stay a constant shade. I guess it must be a limitation of the RPi2

My guess is also that it is the TV causing this. All the cases I have seen it it is because of the TV. If I were you I would check to see if it isn’t as simple as that when you use your playstation it uses your TV:s game mode which I suspect turns off that feature.

With that said, it could be the RPi2.

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I always turn any picture processing settings off on the tv but will recheck all my tv settings again and make sure there is nothing odd going on. I’ll also try a different hdmi cable just in case it’s that.

It’s worth noting that the same thing used to happen with the Playstation 3 when the output was set to rgb limited, changing the ps3 output to rgb full and recalibrating the screen got rid of it completely. This was why I wondered if there was something else I could check on the RPi2 to ensure it was outputting full rgb as after changing the config.txt and running some test assets I was not required to change any tv settings for the RPi2 input.

Recalibrating the screen for the Playstation with full rgb output resulted in very different settings for that particular hdmi input.

Brightness 60
Contrast 48
Colour 38

all other hdmi inputs are currently set

Brightness 54
Contrast 63
Colour 38

I shall report back with my findings.

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I have looked at this again and, same as chenks, I have not been able to get rid of this completely.

I did discover that someone had turned a picture noise reduction setting on to medium, which I turned off. Then I tried a different hdmi lead. This has made things __a little bit ___ better but still noticeable.

The first couple of minutes of Blade Runner is a good example to display the issue, when the names appear on the screen the edges of the screen get noticeably darker than when there is nothing on the screen. The blacks should stay constant throughout these opening credits.

This is not a huge issue by any means, but once you start to notice it you always see it, at least I do anyway.

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@Stewie Griffin said:
This forum software is rubbish by the way
+1 :slight_smile:
It’s not designed to foster exchange, it’s designed to deflect customers calls.