Moire pattern - least on which TV?

[watchthewaves]

One thing that irritates me quite a bit is moire pattern (at least, that's which I think its called).  What I mean is that when very find lines are shown on TV - eg pinstripe shirts/ties, railings far away, etc - when the camera pans, these lines appears to move or be wavy.

 

I didn't have much time today, but I had a quick look at a Panasonic 42PV700 and 42PY700 side by side and thought I saw much less moire patterns on the full HD PY700.  The salesperson told me that the source was a HD source.  From a distance of about 2-3 metres, I couldn't really tell any difference in overall PQ (colour, detail, resolution), but there was very much less moire in the full HD set (I saw the demo showing a cruise ship in the distance - the railings on its deck were much wavier on the PV700).  Has anyone else noticed this?

 

If it was SD instead of HD source, would the results be the same?  Ie, full HD set produce much less moire pattern.

 

I had initially thought that I'd get a HD ready set because there was no significant PQ difference at 42" to me.  But if there is such a big difference in moire pattern, I might have to go with a full HD set.

 

However, just before I left the shop though, I managed to compare the Pioneer 428 with the Panasonic 42PY700.  It was a demo of models on a runway.  Then they cut to an interview with 2 men.  One of them kinda had 2 tone blond-brown hair.  So when he moved his head, I could see the moire patterns.  This time round, I could not see much difference.  Maybe the PY700 was slightly better, but I need to go back and look again to confirm.  Not that the 428 showed less, but that the PY700 showed as much as the 428 did.  Didn't have the time to check with the salesperson whether source was HD or SD though.

 

Bottom line, I need views on which TV has the least moire pattern problem, especially for SD source.  Thanks.

 

 

 

 

[watchthewaves]

errr..... no one as irritated by moire patterns as me?  ???

[Doggie Howser]

Always thought moire patterns were associated with the lower resolution of RF/composite signals. As you improve the definition (going to s-video for instance), the moire patterns tend to disappear.

 

This was with CRTs though. Not sure if the new plasmas/LCDs exhibit these. But that would probably have more to do with scaling artefacts.

 

 

[HardCORE]

One thing that irritates me quite a bit is moire pattern (at least, that's which I think its called).  What I mean is that when very find lines are shown on TV - eg pinstripe shirts/ties, railings far away, etc - when the camera pans, these lines appears to move or be wavy.

 

I didn't have much time today, but I had a quick look at a Panasonic 42PV700 and 42PY700 side by side and thought I saw much less moire patterns on the full HD PY700.  The salesperson told me that the source was a HD source.  From a distance of about 2-3 metres, I couldn't really tell any difference in overall PQ (colour, detail, resolution), but there was very much less moire in the full HD set (I saw the demo showing a cruise ship in the distance - the railings on its deck were much wavier on the PV700).  Has anyone else noticed this?

 

If it was SD instead of HD source, would the results be the same?  Ie, full HD set produce much less moire pattern.

 

I had initially thought that I'd get a HD ready set because there was no significant PQ difference at 42" to me.  But if there is such a big difference in moire pattern, I might have to go with a full HD set.

 

However, just before I left the shop though, I managed to compare the Pioneer 428 with the Panasonic 42PY700.  It was a demo of models on a runway.  Then they cut to an interview with 2 men.  One of them kinda had 2 tone blond-brown hair.  So when he moved his head, I could see the moire patterns.  This time round, I could not see much difference.  Maybe the PY700 was slightly better, but I need to go back and look again to confirm.  Not that the 428 showed less, but that the PY700 showed as much as the 428 did.  Didn't have the time to check with the salesperson whether source was HD or SD though.

 

Bottom line, I need views on which TV has the least moire pattern problem, especially for SD source.  Thanks.

Your observations are true. There will be less moire and screen door effect on full HD TVs because they have more pixels to fit the image in, and 1080i/p source images need to be scaled down less to fit the pixels on the screen.

 

So thats why you saw that the PY700 has less moire. Moire created by the TV's pixel structure happens when the source image has to be scaled down to fit the pixels on the screen. A HD-ready TV has only 1365x768 pixels, while a 1080i/p HD source has 1920x1080 pixels. When you have certain patterns like pinstripes or small tiles, etc. that are more detailed than the 1365x768 pixels of the HD-ready TV, there will be some moire created by the downsizing. Whereas compared to a full HD TV like the PY700 which has 1920x1080 pixels, little to no scaling needs to be done to fit a 1920x1080 pixels source. Too much image sharpening can also lead to some moire.

 

But for SD source, you probably dont need to worry about moire, because the source resolution is something like 640x480 which is fully resolvable even by HD-ready 1365x768 TVs. You may notice that diagonal lines are more jagged on HD-ready vs Full-HD, because of the lower pixel count.

[Darthfunk]

Thats my observation too.

[watchthewaves]

Thanks for the very helpful info guys.

 

Need some further clarification if you don't mind.

 

I expect to be watching mainly a mix of standard broadcast (the standard wall socket connection) and DVD.  I am looking to buying an Oppo, so DVD will likely be upscaled to 1080p.  No cable TV.  No HD player for now.

 

Panel considerations for the moment are:

- Pioneer 428

- Panasonic 42PY700

 

My understanding so far is that (in order of decreasing source resolution):

(1) For pure HD source, moire pattern will almost certainly be less with the PY700.

(2) For DVD upscaled source, moire pattern will also be less on the PY700 (because the panel is getting a HD input).

(3) For standard DVD source, no difference between the 2 panels?

(4) For standard TV broadcast, no difference between the 2 panels?

 

Is my understanding above correct?

One particular question I have -- when a fullHD panel receives the signals in situations (3) and (4) above, it scales it up to 1080p.  So wouldn't there be less moire patterns still?

 

My decision point is this -- assuming I can live with the colours on the PY700, if in all situations it will show less moire, then I am likely to go with it.  If it is some situations only, then I need to see what % of my viewing falls in the "visible difference" part and what % falls in the "no difference" part.

 

Thanks guys.

[HardCORE]

My understanding so far is that (in order of decreasing source resolution):

(1) For pure HD source, moire pattern will almost certainly be less with the PY700.

(2) For DVD upscaled source, moire pattern will also be less on the PY700 (because the panel is getting a HD input).

(3) For standard DVD source, no difference between the 2 panels?

(4) For standard TV broadcast, no difference between the 2 panels?

Just my opinion, but I think that only with the HD source (1) will you see any difference in moire. DVD upscaled will not have the resolution that can cause moire.

 

But you will likely notice more jaggies on any source on the 428. Imagine a diagonal line... try to fit that diagonal line into a square matrix of pixels. The bigger the pixels (hd-ready), the more jagged the line will appear. The smaller/finer the pixel structure (full hd), the smoother the diagonal line will appear.

[watchthewaves]

Thanks.

 

So darn difficult to decide.  Just saw PY500 and 428XG side by side.  Sales chap said default settings.  But the colour looked obviously richer on the 428.  I just wonder with adjustment/calibration, whether the PY500 can come close to the 428XG or not.

 

If not, I will have less moire and jaggies with the PY500 (things which are noticeable to me) but better colour on the 428XG.  Decisions decisions. Aughh!