U.S. CitiesCity-Data Forum Index
Go Back   City-Data Forum > General Forums > Science and Technology > Consumer Electronics
 [Register]
Please register to participate in our discussions with 2 million other members - it's free and quick! Some forums can only be seen by registered members. After you create your account, you'll be able to customize options and access all our 15,000 new posts/day with fewer ads.
View detailed profile (Advanced) or search
site with Google Custom Search

Search Forums  (Advanced)
Reply Start New Thread
 
Old 01-10-2017, 01:40 PM
 
14,781 posts, read 36,594,746 times
Reputation: 14404

Advertisements

Quote:
Originally Posted by JaxRhapsody View Post
It may reduce it's resolution. Laptops usually use an lcd screen, and normally even crt computer screens are higher resolution than most tvs..or used to be. If 1080 is its highest resolution and 4k is higher, the tv may reduce it's resolution. 1080P is the pixel count since beginning with hidef tvs, they're digital.
Quote:
Originally Posted by JaxRhapsody View Post
I'm just going off speculation as 4k tvs are new to me, that if it's a higher resolution than 1080, then wouldn't the TV reduce it's resolution to the 1080 laptop plugged in to it? I'm aware the average laptop has 1080 I have two of them. Other than that, I'm a bit confused to what you're explaining...it kinda looks like the same thing I said.
As Peregrine point out, the TV cannot "reduce the resolution". The TV's resolution is fixed, it's only a matter of whether or not it uses all of the available pixels. A 1080p image that wasn't upscaled would appear as a rectangle taking up about 1/3rd of the screen on a 4k TV. So, the TV has software in it that converts the image into 4k by adding pixels so that the image fills the screen. The downside is that the result of the scaling is highly dependent on the source content and the quality of the TV doing the scaling.

Quote:
Originally Posted by bigbear99 View Post
It's unusual for upscaling to pixelate. Not as if the technology is new. DVD, which IIRC, are 480p, have upscaled for years with great results, ever since flat panel TV came out. I'm sure upscaling is even better with 4K. Not as if technology has been still for the past 15 years.

Wonder what happened to the wallpaper?
It really depends on the wallpaper itself. If it was a "hi-res" image as Peregrine stated, it may have been 4k to being with. The laptop then downscaled the photo to fit on the 1080p laptop screen. It looks great on the laptop. However, when it is plugged into the TV, the TV then is upscaling that image to 4k and all of the processing causes it to look pixellated and lose details. If the original image was a true 1080p image it would most likely scale better on the 4k TV, like his icons and games do.

This article explains the scaling phenomenon well and shows what happens when images are downscaled and then upscaled. You lose a lot of fidelity even when you just take them back to their original size (because you aren't really restoring it to its original state, you are actually upscaling a compressed image).

https://www.cnet.com/news/can-4k-tvs...p-look-better/
Reply With Quote Quick reply to this message

 
Old 01-11-2017, 04:12 PM
 
Location: Louisville KY
4,378 posts, read 4,064,340 times
Reputation: 3706
Quote:
Originally Posted by Peregrine View Post
A TV cannot reduce its resolution. It upscales the signal, be it from a DVD or from a laptop.

OP: just do it.

I plugged in my laptop to my 4K TV. It filled the screen. The wallpaper on my laptop, which is a gorgeous high res photo, looked totally pixelated on the 4K TV because it upscales. Pgoto was 100 x 100 and TV upscaled ot to 400 x 400 (not true numbers). However, the laptop icons and everything on it looked perfect. Playing games looked better then using the laptop screen.
It works perfectly on any 4K TV and probably 90% of laptops out there. I imagine there might be some low end laptops that do not look great attached to 4K.
I just remembering hooking up one of mine to my old tv and it once it got a signal it said PC mode or something and altered the picture accrodingly
Reply With Quote Quick reply to this message
 
Old 01-12-2017, 07:35 AM
 
40,292 posts, read 41,843,525 times
Reputation: 16805
The TV should recognize it's PC, 1080 and adjust appropriately, I know mine does.

Quote:
Originally Posted by bigbear99 View Post
I use a traditional computer/tablet with a traditional 4:3 aspect ratio, so the content would probably be letterboxed on a wider display,
Pillar boxed.

Last edited by thecoalman; 01-12-2017 at 08:03 AM..
Reply With Quote Quick reply to this message
 
Old 01-12-2017, 08:03 AM
 
40,292 posts, read 41,843,525 times
Reputation: 16805
Quote:
Originally Posted by NJGOAT View Post
you should put the TV into "PC mode" which will adjust the display to be in 4:4:4 chroma,
Some TV's are going to be set to overscan, this is legacy support for analog video. I would imagine the important thing with PC mode at least for the average person is overscan will be turned off. Otherwise the start button for example is not going to be 100% viewable.

The overscan are is part of the video and about 5% of the edges that was not displayed on old TV's. It contained information like channel information, CC, copy protection(macrovision) etc. With digital this can be masked with black but not all the time. Direct video from a VCR will not mask it and would be viewable on TV if it was not ovescanning. If you are not viewing material like that you may want to look in the manual for your TV to insure it's not set to overscan because you are not getting the whole picture.
Reply With Quote Quick reply to this message
 
Old 01-12-2017, 08:21 AM
 
40,292 posts, read 41,843,525 times
Reputation: 16805
Quote:
Originally Posted by NJGOAT View Post
It really depends on the wallpaper itself. If it was a "hi-res" image as Peregrine stated, it may have been 4k to being with. The laptop then downscaled the photo to fit on the 1080p laptop screen. It looks great on the laptop. However, when it is plugged into the TV, the TV then is upscaling that image to 4k and all of the processing causes it to look pixellated and lose details. If the original image was a true 1080p image it would most likely scale better on the 4k TV, like his icons and games do.
I'd have to agree with this, it's probably scaling it "on the fly". On a web page for example you can set an images size different than the native size. Newer browsers do a pretty job scaling them on the fly but I think they err on the side of using the least amount of CPU and it's never going to be quite as good as scaling it properly beforehand.

Peregrine, should be easy to test by scaling the image to 1080 in an image editor beforehand. Make sure you turn off anything else like stretch the wallpaper.
Reply With Quote Quick reply to this message
 
Old 01-12-2017, 08:38 AM
 
14,781 posts, read 36,594,746 times
Reputation: 14404
Quote:
Originally Posted by thecoalman View Post
Some TV's are going to be set to overscan, this is legacy support for analog video. I would imagine the important thing with PC mode at least for the average person is overscan will be turned off. Otherwise the start button for example is not going to be 100% viewable.

The overscan are is part of the video and about 5% of the edges that was not displayed on old TV's. It contained information like channel information, CC, copy protection(macrovision) etc. With digital this can be masked with black but not all the time. Direct video from a VCR will not mask it and would be viewable on TV if it was not ovescanning. If you are not viewing material like that you may want to look in the manual for your TV to insure it's not set to overscan because you are not getting the whole picture.
Good points. I think a lot depends on exactly what model of TV you are using as well. I have all Samsungs (with the exception of an old Pioneer Kuro in the formal living room that we only really use occasionally) and when you place it in "PC Mode" (there is one specific HDMI port you have to plug into and then change the input name to PC) it eliminates the overscan as well as all image processing which not only makes everything fit properly on the screen, but also greatly reduces input lag. It also places the display in 4:4:4 chroma which helps sharpen the image, in particular text.
Reply With Quote Quick reply to this message
 
Old 01-12-2017, 09:16 AM
 
Location: Cleveland, Ohio
11,849 posts, read 13,976,351 times
Reputation: 8083
Quote:
Originally Posted by thecoalman View Post
Peregrine, should be easy to test by scaling the image to 1080 in an image editor beforehand. Make sure you turn off anything else like stretch the wallpaper.
It's really not that big a deal.
Reply With Quote Quick reply to this message
Please register to post and access all features of our very popular forum. It is free and quick. Over $68,000 in prizes has already been given out to active posters on our forum. Additional giveaways are planned.

Detailed information about all U.S. cities, counties, and zip codes on our site: City-data.com.


Reply
Please update this thread with any new information or opinions. This open thread is still read by thousands of people, so we encourage all additional points of view.

Quick Reply
Message:

Over $104,000 in prizes was already given out to active posters on our forum and additional giveaways are planned!

Go Back   City-Data Forum > General Forums > Science and Technology > Consumer Electronics
Follow City-Data.com founder on our Forum or

All times are GMT -6. The time now is 03:52 AM.

© 2005-2019, Advameg, Inc. · Please obey Forum Rules · Terms of Use and Privacy Policy · Bug Bounty

City-Data.com - Archive 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35 - Top