Digital Foundry Article Technical Discussion Archive [2014]

[function]

Some TV's automatically set their Game / PC mode to 1:1. Most TVs now have an option that allows you to select it (1:1, or "just scan", or "PC" or something like that).

Standard, default HDTV input settings always enable overscan by default though. At least, I'm yet to come across a display that doesn't do that even in 2014.

 

[Davros]

You know that's basically what overscan is, right?

So your saying that panel makers do put the bezel over some of the pixels ?
why would they do that it makes no sense (it did with crt's)
and if they did how would someone notice tearing in the overscan zone as it would be covered by a bezel

edit: i dont have a tv but a monitor and ive just tested it and every single pixel of its native res is displayed

 

[function]

There aren't pixels under the bezel, but if there were, that's where the image in the overscan area would be.

Effectively, with overscan, the image in the overscan area is beneath where the bezel is. Zoom and crop, basically.

 

[Gerry]

That's a bit rude.

Aye, it was a bit.

 

[Davros]

There aren't pixels under the bezel, but if there were, that's where the image in the overscan area would be.

Effectively, with overscan, the image in the overscan area is beneath where the bezel is. Zoom and crop, basically.

Sorry but your really confusing me now
first you say "There aren't pixels under the bezel" then you say "Effectively, with overscan, the image in the overscan area is beneath where the bezel is"
both cannot be true
If there are no pixels under the bezel why would you have overscan why would you basically tell your 1920x1080 lcd to "create an image that has more pixels than your lcd has, that is larger than 1920x1080 but only display the central 1920x1080 pixels"
that makes no sense at all!!!

also you say "There aren't pixels under the bezel, but if there were, that's where the image in the overscan area would be."
well as there is not that means that there is no image in the overscan area or the overscan area is actually not under the bezel but visible on screen

 

[function]

And yet, it is precisely what happens.

For whatever reason - probably legacy related - the default mode for a 1080p (or other) TV to display a 1080p (or other) image is to scale in incoming image so that the edges of the incoming image are lost off the edges of the TV.

If you *did* have pixels under your bezel (and you don't on an LCD / plasma) that is where the edges of the images would reside. This is the "overscan" area, it is where on a CRT you would typically be scanning beyond ('over') the edges of the visible screen.

I risked death to acheive the glory of getting the entire of my Sega Saturn RGB scart output to display on my cheap ass (but surprisingly good) Grundig CRT. Literally, death. With the back off the TV and while looking at the screen in a mirror I adjusted screws to align the RGB scart image perfectly on the display. This misaligned terrestrial TV and RF input devices, but it mattered not for I had found Glory.

 

[London Geezer]

We all know how overscan works, but in this day and age, surely everyone on this forum who owns a 1080p TV will play their games at 1:1 pixel mapping. Considering the amount of pixel counters and critics vehemently writing about IQ on consoles, the thought that any of us would be playing 1080p games on a 1080p TV with bloody overscan and not at the proper 1:1 pixel ratio, makes my skin crawl.

 

[Davros]

We all know how overscan works,

Actually I'm not sure i do
let me get this right, with overscan you say to your 1920x1080 lcd pretend you have more than 1920x1080 pixels but only display the central 1920x1080 pixels (it doesnt downscale to 1920x1080 pixels, it crops)
is that correct ?

 

[HTupolev]

Sorry but your really confusing me now
first you say "There aren't pixels under the bezel" then you say "Effectively, with overscan, the image in the overscan area is beneath where the bezel is"
both cannot be true
If there are no pixels under the bezel why would you have overscan why would you basically tell your 1920x1080 lcd to "create an image that has more pixels than your lcd has, that is larger than 1920x1080 but only display the central 1920x1080 pixels"
that makes no sense at all!!!

In most modes, modern TVs scale incoming images up a little and chop of the edges.

Physically speaking, TV manufacturers don't put any screen underneath the bezel, but that's "where the outer edges of the image would be" if they didn't get cropped away after the upscale.

 

[Shortbread]

Console gaming has been reduced to arguing about minor dips, slight stutters, rare screen tearing and other anomalies PC gamers have come to except across all manners of hardware configurations. That’s not to say PC gamers don’t argue over frame-rates (AMD vs. NVidia vs. Intel)… but not over minuscule 1-3 frames (dips) that mean nothing in the long run.

 

[London Geezer]

Actually I'm not sure i do
let me get this right, with overscan you say to your 1920x1080 lcd pretend you have more than 1920x1080 pixels but only display the central 1920x1080 pixels (it doesnt downscale to 1920x1080 pixels, it crops)
is that correct ?

No, Just think of the TV 'zooming' on the full image, so that the very edges of the image would be off screen. That's overscan. It means that a 1080p will be displayed completely wrong as the TV will display fewer pixels and also add a nice layer of processing to zoom on the picture.
It's disgusting.

 

[London Geezer]

Every time a 1080p TV overscans a direct 1080p image, a kitten dies.

 

[function]

We all know how overscan works, but in this day and age, surely everyone on this forum who owns a 1080p TV will play their games at 1:1 pixel mapping. Considering the amount of pixel counters and critics vehemently writing about IQ on consoles, the thought that any of us would be playing 1080p games on a 1080p TV with bloody overscan and not at the proper 1:1 pixel ratio, makes my skin crawl.

Then set your skin mode to crawl, LB, because like people failing to recognise the Dreamcast as our one true King (that died for our sins at age 33 months on the X of the PS2 pad) the curse of overscan is not actually so well known about!

 

[Deleted member 11852]

If there are no pixels under the bezel why would you have overscan why would you basically tell your 1920x1080 lcd to "create an image that has more pixels than your lcd has, that is larger than 1920x1080 but only display the central 1920x1080 pixels"
that makes no sense at all!!!

Every LCD TV they I've encountered is not mapping pixels 1:1 to native resolution of the panel by default, this includes high end Sony and Samsung TVs. My Bravia X8505 4K bought brand new in August had to be set to pixel 1:1 mode.

By default they 'play safe' and do not show the small border of image that traditionally was hidden by overscan on CRTs, they do this by scaling up ever so slightly - and losing the very edges of the image being output by any connected device.

When the TV is setup like this you won't notice tearing in the overscan area because it's not visible. Put the TV into 1:1 pixel or native pixel (different manufacturers have different terms for it) and it will be visible. Barely.

 

[London Geezer]

Every LCD TV they I've encountered is not mapping pixels 1:1 to native resolution of the panel by default, this includes high end Sony and Samsung TVs. My Bravia X8505 4K bought brand new in August had to be set to pixel 1:1 mode.

By default they 'play safe' and do not show the small border of image that traditionally was hidden by overscan on CRTs, they do this by scaling up ever so slightly - and losing the very edges of the image being output by any connected device.

The problem is not with losing the edges of the image, which would be bad enough. The kitten-murdering uber stupid thing is the TV actually upscaling a 1080p image - on a 1080p screen, paradoxically - introducing what we all know gets introduced when an image is upscaled: apocalypse.

 

[Deleted member 11852]

The problem is not with losing the edges of the image, which would be bad enough. The kitten-murdering uber stupid thing is the TV actually upscaling a 1080p image - on a 1080p screen, paradoxically - introducing what we all know gets introduced when an image is upscaled: apocalypse.

Yeah. Although when you have 4x the pixels on the panel, scaling a 1080p native image is less impactful but I still turned that overscan crap off and enabled 1:1 on my Bravia.

I don't care if I can't see it, I know it's there!

 

[AlNom]

Ewwwww TEARING! So gross.

Cry me a shader. :3

 

[function]

Watchdogs WiiU:

http://www.eurogamer.net/articles/digitalfoundry-2014-vs-watch-dogs-on-wii-u

Seems like a decent port, but performance suffers a bit compared to the PS3 version. CPU mebbe?

 

[pjbliverpool]

The problem is not with losing the edges of the image, which would be bad enough. The kitten-murdering uber stupid thing is the TV actually upscaling a 1080p image - on a 1080p screen, paradoxically - introducing what we all know gets introduced when an image is upscaled: apocalypse.

I actually had no idea about this so thanks for the tip. I've now changed my TV's settings!

 

[function]

Wut. London Boy stealing my glory. Again.