Motion artifacts with large LCD screens. - Canadian TV, Computing and Home Theatre Forums
 
LinkBack Thread Tools Search this Thread Display Modes

post #1 of 12 (permalink) Old 2007-10-21, 11:59 AM Thread Starter
 
Join Date: Jan 2003
Location: montreal
Posts: 321
Motion artifacts with large LCD screens.

A friend from work called me up to tell me that with his Illico 8300HD, he gets motion artifacts (moving tennis balls look like comets) on his new Sony 52" XBR4.

The XBR4 supports 1080p and has a 120 hz. frame doubler, if I understand correctly.

He views from his sofa at 10' away, but if he backs up another 2', he claims he is less bothered by the artifacts.

He says that static images are perfect at any distance.

He has an opportunity to exchange his XBR4 for a smaller screen and I felt that he should keep the larger one and wait until the day when the sport channels (like TSN-HD) can transmit fast motion sports with less compression.

I use an old 34" crt, so I am in a poor position to offer him advice.

Do any of you know the degree to which a 720p sports program is compromised by the way it's originally recorded and transmitted over Videotron?

Does his high performance 1080p screen tend to make any shortcomings in TSN-HD more apparent?

Do larger LCD screens amplify the inherent problems of TSN-HD?

Thanks
P.S. He uses Auto-HDMI handshaking and forcing the Illico into Upconvert-1 or Upconvert-2 does not change the degree of blurring.

Montreal
montreal is offline  
Sponsored Links
Advertisement
 
post #2 of 12 (permalink) Old 2007-10-21, 12:17 PM
 
Join Date: Feb 2006
Location: STMDN,Qc
Posts: 106
The minimum watching distance if I remember is 1.87 the diagonal and up to 5 time the diagonal is the maximum so put 52inch so minimum is about 8ft and maximum is 21-22 ft

so between that range he should see a good picture...but there is compression made by all the company (dish and cable company)....
jtheman is offline  
post #3 of 12 (permalink) Old 2007-10-21, 12:50 PM
57
Moderator
 
Join Date: May 2002
Location: Toronto, Rogers, 9865 & 8300-eHDD, Sharp LC75N8000U, Denon AVR4310Ci; Sony KDL40W3000, 9865
Posts: 56,242
A proper setup of the TV may help: See:

http://www.digitalhome.ca/forum/showthread.php?t=17713

Also, due to the limitations of the broadcast and MPEG (and perhaps the service provider), you can often see macroblocking or compression artifacts on fast moving material - this is more noticeable, the larger the screen, and the closer you are.

http://www.digitalhome.ca/forum/showthread.php?t=17715

http://www.digitalhome.ca/forum/showthread.php?t=17705 (Size)

57's Home Theatre (Latest equipment & photos)
57 is offline  
 
post #4 of 12 (permalink) Old 2007-10-22, 07:55 AM
 
Join Date: Dec 2005
Posts: 332
57 is absolutely correct, and I had the same experience when I got my 46" SONY Bravia LCD and got nervous with the amount of visible compression artifacts at first. Moreover I was coming from a 32" Sony CRT HDTV so the change for me was even more drastic. With the appropriate view distance, your fiend will get used to the artifact and not even notice them after a few weeks.
EnderWiggin is offline  
post #5 of 12 (permalink) Old 2007-10-22, 01:12 PM Thread Starter
 
Join Date: Jan 2003
Location: montreal
Posts: 321
Hi again, this is the original poster.

Thanks for all your comments and suggestions.

My friend reports to me today that he rented an action DVD and he could not detect any motion problems, so he is now convinced that his artifacts have more to do with the way the original program from TSN-HD is compressed and re-distributed over Videotron.

After going back to the stores, he comments that 46" seems too small a screen and 52" is too large.

I would like to be in his situation, having the luxury of choosing one or the other.

Personally I'm stuck with my 2002 vintage 34" XBR CRT (850 lines of horizontal resolution) which I paid $4k for, so a replacement for me is out of the question for another 5 years.

Montreal
montreal is offline  
post #6 of 12 (permalink) Old 2007-10-22, 02:56 PM
57
Moderator
 
Join Date: May 2002
Location: Toronto, Rogers, 9865 & 8300-eHDD, Sharp LC75N8000U, Denon AVR4310Ci; Sony KDL40W3000, 9865
Posts: 56,242
DVDs don't usually have artifacts because:

1. They're not HD.

2. They have "variable bit-rate" and can be encoded to minimize any artifacts.

3. Live HD programming cannot have this done, so the artifacts are a "fact of life".

57's Home Theatre (Latest equipment & photos)
57 is offline  
post #7 of 12 (permalink) Old 2007-10-22, 03:04 PM Thread Starter
 
Join Date: Jan 2003
Location: montreal
Posts: 321
Quote:
Originally Posted by 57 View Post
DVDs don't usually have artifacts because:

1. They're not HD.

2. They have "variable bit-rate" and can be encoded to minimize any artifacts.

3. Live HD programming cannot have this done, so the artifacts are a "fact of life".
Thanks 57,

I think my friend needed to see a action DVD in order to believe that the artifact problem on his screen was neither related to the type of screen he was using (LCD) nor the size of the screen (52") relative to his 10' viewing distance.

Even if he switched to a slightly smaller screen and/or to plasma, he would most likely continue to experience the same motion blurring when viewing TSN-HD. Knowing this will save him the trouble of needlessly hauling his TV back to the store for an exchange.

Thanks again.

Montreal
montreal is offline  
post #8 of 12 (permalink) Old 2007-10-22, 03:30 PM
57
Moderator
 
Join Date: May 2002
Location: Toronto, Rogers, 9865 & 8300-eHDD, Sharp LC75N8000U, Denon AVR4310Ci; Sony KDL40W3000, 9865
Posts: 56,242
A proper setup of the TV is important. If his TV is still in its original default picture mode, there is too much edge enhancement, too much contrast and sharpness, which exacerbates the situation. See the first link in post 3.

57's Home Theatre (Latest equipment & photos)
57 is offline  
post #9 of 12 (permalink) Old 2007-10-22, 03:50 PM Thread Starter
 
Join Date: Jan 2003
Location: montreal
Posts: 321
Thanks for reminding me that the factory default settings are never optimal.

I am invited tomorrow to view his new TV and I'll see what sort of edge-enhancement controls there is in his user menu.

I have personal experience tweaking the setup of my old 34XBR800 using the service menu.

I'll bring over my AVIA tuning DVD.

It will be up to him to decide if he wants to invest in an ISF tuneup.

Montreal
montreal is offline  
post #10 of 12 (permalink) Old 2007-10-23, 05:07 PM Thread Starter
 
Join Date: Jan 2003
Location: montreal
Posts: 321
I had the good fortune to view my friend's 52" XBR4 this morning and the menu control for the Picture Mode was set to VIVID. We reduced it to MOVIE, and that softened the image. The edge enhancement was already off as well as the DRC, which I believe is a line doubler for only 480i SD inputs.

My friend has an older Panasonic DVD player which has a menu selectable progressive mode, but in spite of being in PROGRESSIVE, the Sony XBR4 identified the source as being "480i SD".

I told him the DVD images would probably look better if the TV was upconverting a 480p DVD signal to 1080p instead of upconverting the current 480i to 1080p.

So Videotron remains the weakest link in the chain where motion artifacts are concerned.

Thanks again for all your comments, much appreciated by both of us.

Montreal
montreal is offline  
post #11 of 12 (permalink) Old 2007-10-23, 05:17 PM
57
Moderator
 
Join Date: May 2002
Location: Toronto, Rogers, 9865 & 8300-eHDD, Sharp LC75N8000U, Denon AVR4310Ci; Sony KDL40W3000, 9865
Posts: 56,242
Quote:
DVD....menu selectable progressive mode
There may also be a hard switch on the back of the DVD player. If the Sony identified it as 480i, then it was not 480P, but should be with the proper settings in the DVD player menu (and any hard switches.) You, of course, need to use component video cables from the player, not S-video or composite.

57's Home Theatre (Latest equipment & photos)
57 is offline  
post #12 of 12 (permalink) Old 2007-10-23, 05:27 PM Thread Starter
 
Join Date: Jan 2003
Location: montreal
Posts: 321
Quote:
Originally Posted by 57 View Post
There may also be a hard switch on the back of the DVD player. If the Sony identified it as 480i, then it was not 480P, but should be with the proper settings in the DVD player menu (and any hard switches.) You, of course, need to use component video cables from the player, not S-video or composite.
We looked for a hard switch (as found on the back of my own DVD player), but there was none on his, which explains why the switch was a soft one controlable from his DVD player setup menu.

And he was using component cables as well, so if the TV says it's getting 480i, then his player must be defective.

He plans to get a Blu-Ray player eventually and at time I imagine he will transmit over HDMI at 1080p24 and get flawless images with very few motion artifacts, if any.

Montreal
montreal is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Canadian TV, Computing and Home Theatre Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in










Thread Tools Search this Thread
Show Printable Version Show Printable Version
Email this Page Email this Page
Search this Thread:

Advanced Search
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome