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post #1 of 38 Old 10-21-2007, 06:32 PM - Thread Starter
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Is there a huge quality difference between SP (2 hour) and LP (3 hour) and EP (4 hour) recording levels?

Background:
I am not an audio/videophile. I do not have HDTV. Just your basic TV with basic (not digital) cable. The picture looks great to me. I do see a difference when I see HDTV TVs, but not enough that I care to invest in one.

I am recording football games in SP mode, which takes two discs. It would be nice to get a game on one disc just for convenience of not having to switch discs in the middle of watching a game. With editing, I can get many games to LP (3 hours), but some college games can't be edited to 3 hours, believe it or not.

From what I've read here, I'm guessing most folks are much more sophisticated than I in matters of video quality. I have tried taping games in different modes, and when I compare them, I don't see much if any difference. Maybe a slight difference, but it's hard to tell for sure if there is a difference or if my expectations of a difference are influencing me. If it matters, I'm using a Philips 3575 HDD model. I didn't burn the test EP or LP clips to DVD as I didn't want to waste a DVD. I just watched the clips directly from the HDD. Don't know if that makes a difference.

Well, this is a pretty crazy post, asking folks to help me decide how I should record my own programs for my own enjoyment. Nevertheless, it is what it is. I'm open for your input. Is there anyone else out there who can't tell a difference in SP versus EP? Or my eyes just that bad?

Thanks,

Chris
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post #2 of 38 Old 10-21-2007, 06:55 PM
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I've done test after test trying to figure out why/how the Philips 3575 seems able to record sports at the longer rec. modes with little or no apparent difference.

Baseball and basketball look great at 3-hr-LP and even very good at 4-hr-EP and OK at 6-hr-SLP if the source is good, like a digital HD channel (even tho we know it's downrezd to SD)...and I'm on analog cable to boot.

I've done lots of football and finally had an "epiphany"...even football looks great on the 3575's digital channel at the long rec. modes for all cameras except maybe the long-shot stadium camera. When they pull back and show almost the entire field, and the players running in diff. directions are ONLY 1/2" TO 1" TALL on the screen.

MPEG2 is predictive in nature and it can easily handle fast movement IF it's predictable, like a car race (2.5 Mbps w/little variation from all cameras, inside car, pan shots, on-track shots, etc.), but when those little 1/2" buggers start jigging and jagging all over the big green field, it has a little problem making accurate predictions of the movement.

Even on the long shots, it seems they quickly zoom closer to the action and then even SLP looks OK.

So, to me anyway, a 3-hr-LP recording of a football game from a digital channel with the 3575 is ideal for quality and time coverage, even if there is some slight degradation for those short periods when the stadium camera is on its longest shots.

All bets are off on a std SD channel. I was very surprised one time at a pre-season Monday Night game which didn't record well at almost ANY rec. mode...live shots in the booth were brilliant but the "live" game play looked like a not-so-good pre-recording...very weird one-time situation, I hope.

By the way, don't worry about the dub to DVD...all my tests have been done thru the last step of making a high-speed dub...looks the same as the HDD original.
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post #3 of 38 Old 10-21-2007, 07:22 PM - Thread Starter
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Quote:
Originally Posted by wabjxo View Post

I've done test after test trying to figure out why/how the Philips 3575 seems able to record sports at the longer rec. modes with little or no apparent difference.

Baseball and basketball look great at 3-hr-LP and even very good at 4-hr-EP and OK at 6-hr-SLP if the source is good, like a digital HD channel (even tho we know it's downrezd to SD)...and I'm on analog cable to boot.

I've done lots of football and finally had an "epiphany"...even football looks great on the 3575's digital channel at the long rec. modes for all cameras except maybe the long-shot stadium camera. When they pull back and show almost the entire field, and the players running in diff. directions are ONLY 1/2" TO 1" TALL on the screen.

MPEG2 is predictive in nature and it can easily handle fast movement IF it's predictable, like a car race (2.5 Mbps w/little variation from all cameras, inside car, pan shots, on-track shots, etc.), but when those little 1/2" buggers start jigging and jagging all over the big green field, it has a little problem making accurate predictions of the movement.

Even on the long shots, it seems they quickly zoom closer to the action and then even SLP looks OK.

So, to me anyway, a 3-hr-LP recording of a football game from a digital channel with the 3575 is ideal for quality and time coverage, even if there is some slight degradation for those short periods when the stadium camera is on its longest shots.

All bets are off on a std SD channel. I was very surprised one time at a pre-season Monday Night game which didn't record well at almost ANY rec. mode...shots in the booth were brilliant but the game play looked like a not-so-good pre-recording...very weird one-time situation, I hope.

By the way, don't worry about the dub to DVD...all my tests have been done thru the last step of making a high-speed dub...looks the same as the HDD original.

Thanks wabjxo. I'm surprised but very pleased to hear you're not seeing much difference. Maybe my eyes aren't so bad. As you noted, you are on digital channels and I'm on standard, but it's still good to hear your perspective. I'm going to try some games on LP and EP. The only thing I like about SP is that I don't have to do much editing, just a bit of trimming and then a 'title divide' at halftime. I just leave all the commercials and halftime shows in there (I actually enjoy watching old commercials, though it will be 15+ years before I consider these 'old'!). I think NFL games can generally be edited to under 3 hours, but college games might be tougher, in which case I can just leave them unedited and run on EP.

Thanks again,

Chris
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post #4 of 38 Old 10-21-2007, 07:28 PM
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Newer Panasonic recorders make the best LP recording, just about the same visual quality as the SP speed on Panasonic recorders. According to reviews, the 4 hour speed records at 500 lines resolution. Screen captures I made of Panasonic LP recorded video show the captures to be full D1 images (720x480 pixels).

To check the difference between SP and LP, if you have a DVD of a movie that is also going to be broadcast you could record the broadcast on a DVD-R and then use free software like VLC media player to capture the same image from both sources on your computer. My experience is that LP recordings made on units without Panasonic's new technology are adequate as long unless there are not dark scenes, whose video image is helped by the greater detail that the new Panasonic LP recording technology provides. I gave up on LP recording in favor of Flexible Recording on my old Panasonic, which gave me about 160 minutes of near identical SP quality recording at the FR setting.

Everything is subjective, though.
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post #5 of 38 Old 10-21-2007, 10:43 PM
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Quote:
Originally Posted by opieandy View Post

Is there a huge quality difference between SP (2 hour) and LP (3 hour) and EP (4 hour) recording levels?
I have tried taping games in different modes, and when I compare them, I don't see much if any difference. Maybe a slight difference, but it's hard to tell for sure if there is a difference or if my expectations of a difference are influencing me.

I use the rule that if I can't see much difference -
then (obviously) there isn't much difference to me

OK I recently got a cheapo SV2000/WV10D6 DVD recorder from WalMart for all of $49.97 -
please click on SV2000 WV10D6 DVD Recorder from WalMart where there is a lot of details of my impressions -
especially on the different recording modes/speeds.

I used GSpot to examine the recordings from the SV2000/WV10D6 -

HQ (1hour) and SP (2hour) - full DVD resolution of 720x480

all other speeds/modes -
SPP(2.5hr), LP(3hr), EP(4hr) and SLP(6hr) - drops to CVD (China Video Disc at Wikipedia) at 352x480 resolution.

Like you, I could not see much difference between the recordings -
except for SLP(6hr) which can show motion and edge artifacts -
but still more than acceptable for program shifting.

I didn't even know what CVD was, and had to look it up.

With hindsight this drop in resolution (to CVD at 352x480) makes sense -
otherwise how else could so much video information be recorded on a single DVD?

The main differences between the recordings - other than DVD-CVD - was the bit rate, and therefore Qf (Quality Factor at Wikipedia)

SP(2hr) = 4339 kbps, Qf = 0.419 (bits/pixel)/frame
EP(4hr) = 2032 kbps, Qf = 0.401 (bits/pixel)/frame

So the Qf for SP and EP are similar - the only real difference is the respective resolution (DVD 720x480 for SP, and CVD 352x480 for EP).

For me, I record at SP(2hr) only if the program is special, otherwise I am quite happy with EP(4hr) - this is even when I know the resolution is half that of SP - it's just that I cannot see much difference - at least on my 27" analog CRT TV.

It may be a limitation of my equipment, or eyes -
but it doesn't matter -
I can't see a difference.

The occassional SP recordings are worth it to me, because some day I may get a HDTV - and then I might be able to see a difference........
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post #6 of 38 Old 10-21-2007, 11:51 PM
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Quote:
Originally Posted by UnknownVT; View Post

The occassional SP recordings are worth it to me, because some day I may get a HDTV - and then I might be able to see a difference........

Yes, you will definitely notice a difference with a HDTV, and a larger screen. Anything you think you will really want to watch then should be recorded in SP, or better.
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post #7 of 38 Old 10-22-2007, 04:26 AM
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Just try a recording at the lower rates (a few minutes should tell you) and judge for yourself!
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post #8 of 38 Old 10-22-2007, 08:56 AM
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Quote:
Originally Posted by RCbridge View Post

Just try a recording at the lower rates (a few minutes should tell you) and judge for yourself!

This is exactly the thing to do. Other people here aren't in a very good position to offer you advice because they're not seeing what you see with your TV and viewing distance, and they may or may not have the same type of sensitivities to the kinds of posterization and motion artifacts that get worse with the longer recording speeds. You're really the only person who can decide what's acceptable to you.

But as other posters have cautioned, if you ever plan to upgrade your display then be aware of the possiblity that you'll be disappointed with your recordings. If you know someone with an HDTV, burn some test footage at different quality settings onto a disk and take it to their place to evaluate it. Then you'll be in an informed position to make a decision for yourself.
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post #9 of 38 Old 10-22-2007, 11:43 AM
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Quote:
Originally Posted by kjbawc View Post

Yes, you will definitely notice a difference with a HDTV, and a larger screen. Anything you think you will really want to watch then should be recorded in SP, or better.

Thank you, that's what I figured.

Be grateful if you'd please explain why an HQ(1hr) recording would be better than SP(2hr)
- other than the obvious - "it should be"

It would appear that it is more likely due to the limitation of my current equipement that I can't see much difference between SP and EP(4hr) - although I was somewhat taken aback that any recording below SP used CVD 352x480 resolution on my DVD recorder (SV2000 WV10D6) -

I was surprised I was still not able to see much difference
(even when I knew there was a different of half the resolution) -
especially since I can easily see a difference between British 625 line PAL (720x576) and US NTSC (720x480) on analog CRT TVs -

So I would have thought being able to see a difference between NTSC DVD 720x480 and CVD 352x480 should have been easy.....
perhaps horizontal resolution on scanned-line/CRT picture is somewhat more "forgiving"?

Bear in mind also all DVD recorders only record at 480i,
for now there are no 1080p HDTV capable DVD recorders available on the current consumers market -
so our transition over to true 1080p HDTV is probably going to relatively painful.......
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post #10 of 38 Old 10-22-2007, 02:58 PM - Thread Starter
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Quote:
Originally Posted by Sean Nelson View Post

This is exactly the thing to do. Other people here aren't in a very good position to offer you advice because they're not seeing what you see with your TV and viewing distance, and they may or may not have the same type of sensitivities to the kinds of posterization and motion artifacts that get worse with the longer recording speeds. You're really the only person who can decide what's acceptable to you.

But as other posters have cautioned, if you ever plan to upgrade your display then be aware of the possiblity that you'll be disappointed with your recordings. If you know someone with an HDTV, burn some test footage at different quality settings onto a disk and take it to their place to evaluate it. Then you'll be in an informed position to make a decision for yourself.

Thanks, guys, for the help and advice.

You are exactly right - it's in the eye of the beholder. I only ask because sometimes I watch old games with friends, and they might be more perceptive on video quality. But if my eyes are not deceiving me, there's not much of a difference. Also, I've thought of trading games I don't want to someone else for games I do want (still researching whether that's legal, but I think it is if you are not selling the games), and I wouldn't want to trade a game to someone that they thought was junk because of lesser quality recording. On the other hand, if you're just trading, does it really matter?

I think I mentioned in the first post that I did record snippets in various modes and couldn't see much/any difference. But, I am not picky and don't tend to notice video quality differences (e.g., I don't feel the "WOW" that some others do when we're both staring at the same HDTV screen...I'm thinking, "What are they seeing that I'm not seeing? Just looks like a normal picture to me."

Anyway, I'm going to actually record tonight's MNF game in EP (4 hour mode), burn it to a single disc, watch it, and see if the whole experience (including the side benefit of only having to burn to one disc, not having to divide the title into smaller segments, etc.) pushes me over the edge to EP.

Chris
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post #11 of 38 Old 10-22-2007, 03:05 PM
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Quote:
Originally Posted by opieandy View Post

Anyway, I'm going to actually record tonight's MNF game in EP (4 hour mode), burn it to a single disc, watch it, and see if the whole experience (including the side benefit of only having to burn to one disc, not having to divide the title into smaller segments, etc.) pushes me over the edge to EP.

That'll be a good test of the EP mode, but I'm curious...why 4-hr-EP? The actual game is only 3 hrs (7:30-10:30 CST), so ideal for 3-hr-LP.

Also, will you be recording the game from a SD or a digital channel?

ESPN is broadcasting the game and they usually have both an analog SD channel and a digital HD channel of the same game. Besides game length, the quality of the source is the biggest factor in "acceptable" PQ, esp. with football, so the digital channel will be OK to record in 3-hr-LP or 4-hr-EP, but the SD channel might not be OK at 4-hr-EP.

In a previous post you mentioned that you were on "standard" channels and I was on digital, but I'm actually on basic analog cable and even so am able to receive 6 free digital channels in that SD analog feed. So, I'm curioser now to find out if you receive ANY digital channels with whatever service you're on?
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post #12 of 38 Old 10-22-2007, 03:26 PM
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On my Panasonic recorder (DMR-EH75V), the 1-hour mode (which it calls XP) is indistinguishable from 2-hour mode (SP) in normal playback, both on my 32" LCD HDTV and on my computer monitor. I do see a slight difference when looking at individual frames in single-frame or very slow-motion mode. The SP frames have noticeable compression artifacts near sharp edges, similar to what you see when you save a JPEG image at a lower-quality setting. The XP frames have almost no such artifacts.

I just tried recording samples from a local HD news program in SP, LP (4 hour) and EP (6 hour) modes. SP and LP were very close, both in normal playback and in slow motion, including a rapidly-moving animated logo that introduces the program. This supports the idea that a clean digital source with little or no image noise should compress well.

The EP sample was noticeably less crisp, although still smooth, without much if any blockiness.

I'll try LP for one of the World Series games and see how it turns out. I recorded the American League series in FR (flexible) mode at a rate of 1:30 or 1:40 per disc, so each game just about fills up two discs, except for the one which ran into extra innings (three discs).
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post #13 of 38 Old 10-22-2007, 03:28 PM
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Quote:
Originally Posted by opieandy View Post

(e.g., I don't feel the "WOW" that some others do when we're both staring at the same HDTV screen...I'm thinking, "What are they seeing that I'm not seeing? Just looks like a normal picture to me.")

Actually it's the other way round for me

I see how bad/cruddy some broadcasts are on HDTV -
where I probably would not have even commented on regular analog crt TVs -

This is mainly in pixellation or breakdown of detail in images -
like crowd scenes in games - on true HDTV Hi-Def digital broadcast it is "amazing", but on a non-HD broadcast it just looks horrible -
to the point I probably prefer to be watching it on a crummy analog crt TV.

So our display device counts for a lot - and I think (don't know) that analog crt/interlaced TV may not be quite so revealing of lack of horizontal resolution - hence my satisfaction of EP(4hr) mode even though I know it's the lower CVD 352x480 resolution......

Whereas on a LCD/Plasma non-interlaced HDTV this would probably become much more revealing.

So I would say for progarms one would want to keep, or want to lend/exchange with people with HDTVs - record with SP at the full DVD 720x480 resolution.

Otherwise EP would seem "good enough" -
but bear in mind in once we have a HDTV - this may no longer be true........
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post #14 of 38 Old 10-22-2007, 03:42 PM
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Quote:
Originally Posted by UnknownVT View Post

Actually it's the other way round for me

I see how bad/cruddy some broadcasts are on HDTV -
where I probably would not have even commented on regular analog crt TVs -

This is mainly in pixellation or breakdown of detail in images -
like crowd scenes in games - on true HDTV Hi-Def digital broadcast it is "amazing", but on a non-HD broadcast it just looks horrible -
to the point I probably prefer to be watching it on a crummy analog crt TV.

So our display device counts for a lot - and I think (don't know) that analog crt/interlaced TV may not be quite so revealing of lack of horizontal resolution - hence my satisfaction of EP(2hr) mode even though I know it's the lower CVD 352x480 resolution......

Whereas on a LCD/Plasma non-interlaced HDTV this would probably become much more revealing.

So I would say for progarms one would want to keep, or want to lend/exchange with people with HDTVs - record with SP at the full DVD 720x480 resolution.

Otherwise EP would seem "good enough" -
but bear in mind in once we have a HDTV - this may no longer be true........

I was "treated" to a sickening illustration of this at my local Sears, where a very helpful sales lady showed us all the HDTV flat panels and, as we began to discuss PQ, she bravely mentioned that we would probably need to upgrade our cable service to HD or we might be surprised. She said several people have bought their first HDTV flat panel from them, got home, and then complained loudly that the picture was lousy...not at all like in the store.

Well, these people had basic analog cable, so she illustrated for us how that would look at home if we didn't upgrade our basic analog cable. They had Dish satellite signal, so she switched to basic analog type signal, and the picture WAS "disappointing."

Needless to say, since I sorely hate to give a cell phone company a chance to add fees-on-fees ("feefees"), or the tel. co. to do the same, I'm dreading being forced to upgrade my cable service and give them a chance to add some more feefees on my bill...but, apparently, my new flat panel (if I ever get one now) won't do me much good unless I do!
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post #15 of 38 Old 10-22-2007, 03:50 PM
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Quote:
Originally Posted by jtbell View Post

I'll try LP for one of the World Series games and see how it turns out. I recorded the American League series in FR (flexible) mode at a rate of 1:30 or 1:40 per disc, so each game just about fills up two discs, except for the one which ran into extra innings (three discs).

I bet you'll like the baseball game at the Panny's 4-hr-LP mode. Baseball is much easier to record than football...men are several inches taller and run in more predictable directions!

I'm going to record the MNF game on ESPN HD via my basic analog cable in 3-hr-LP with my Philips 3575. Everything should be good except those 1/2" men, with their 1/32" numbers, all running in different directions, and shot by the stadium camera 3 miles away!
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post #16 of 38 Old 10-22-2007, 06:31 PM
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Quote:
Originally Posted by wabjxo View Post

Baseball is much easier to record than football...men are several inches taller and run in more predictable directions!

And most of the time they're just standing around waiting for something to happen.
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post #17 of 38 Old 10-22-2007, 06:34 PM
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Originally Posted by jtbell View Post

And most of the time they're just standing around waiting for something to happen.

...or spittin'. Wonder how that'll record!?
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post #18 of 38 Old 10-22-2007, 10:14 PM
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Quote:
Originally Posted by UnknownVT View Post

Thank you, that's what I figured.

Be grateful if you'd please explain why an HQ(1hr) recording would be better than SP(2hr)
- other than the obvious - "it should be"

I have a Samsung 720p 56" DLP set, and a Pio 640 DVDR. Recording an SD source at SP is very good, I can barely, if ever, tell it from the original. But, my Pio offers such recording flexibility, that I set the highest possible bit-rate that will let me get the whole program on a single disc. If it is an hour program, not part of a series, that means XP. I cannot, ever, tell XP from the original. A 90 min. movie won't be XP, but it will be a higher bit-rate. Why not use the extra disc space? Maybe I will be able to see the difference when I get a 1080p DLP set.

The only time when I can see a small difference between SP, and rather higher bit-rates, is when I am recording from a HD source, down-rezzed, of course. This produces a DVD with a PQ virtually indistinguishable from a commercial, non-anamorphic disc. Sadly, my Comcast Moto DVR will not let me make an anamorphic DVD, but if I could...
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post #19 of 38 Old 10-22-2007, 11:36 PM
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Quote:
Originally Posted by kjbawc View Post

I cannot, ever, tell XP from the original. A 90 min. movie won't be XP, but it will be a higher bit-rate. Why not use the extra disc space? Maybe I will be able to see the difference when I get a 1080p DLP set.
The only time when I can see a small difference between SP, and rather higher bit-rates, is when I am recording from a HD source, down-rezzed, of course. This produces a DVD with a PQ virtually indistinguishable from a commercial, non-anamorphic disc.

Many thanks for the explanation - please bear with me, I am still learning...

Does a higher bit rate actually affect resolution?
I thought it mainly affected the smoothness of motion -
ie: less motion artifacts.

The bit rate determines the Qf (Quality Factor - Wikipedia) -
I found on my cheapo SV2000 WV10D6 DVD recorder
using GSpot on varying recording modes/speeds -

1hour(HQ) = 8948 kbps, Qf= 0.864 (bits/pixel)/frame
2hour(SP) = 4339 kbps, Qf = 0.419 (bits/pixel)/frame
4hour(EP) = 2032 kbps, Qf = 0.401 (bits/pixel)/frame
6hour(SLP) = 1312 kbps, Qf = 0.259 (bits/pixel)/frame
(anything lower than SP(2hr) is recorded at lower CVD 352x480 resolution)


Wikipedia says about Qf - "a good rule of thumb is to keep the Qf somewhere between 0.20 and 0.28 and encoding to Qf values over 0.30 is just a waste of bits:"

This obviously didn't hold for me as I could definitely see both motion and edge artifacts on the lowest SLP(6hr) recordings even on my cheapo 27" analog crt TV, and SLP(6hr) had a Qf = 0.259 (bits/pixel)/frame which is actually in the upper part of that range.
BUT I can understand what they are trying to explain about wasted bits.....

Both 2hr(SP) and 4hr(EP) have Qf of around 0.4+ - and they do look pretty good (at least on my limited equipment) -

Just for a control reference comparison -
I took GSpot meaurements off of Terminator 2 - T2 Extreme DVD
(which has a high rep for quality) -

chapter 4 (sequence right after the titles - sharp, high detail) -
5083 kbps, Qf = 0.491 (bits/pixel)/frame
chapter 12 (asylum scene - somewhat less detail - scenes showing TV screen)
3596 kbps, Qf = 0.347 (bits/pixel)/frame

so the Qf varies from about 0.35 to 0.5 - now this is a very well mastered commerical DVD, and kind of hard to fault - the mid/average Qf was about 0.425.

So what would a higher bit rate (therefore higher Qf) over that of a good DVD like the T2 Extreme DVD really gain?
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post #20 of 38 Old 10-23-2007, 12:17 AM
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Well, hopefully someone here more knowledgeable than I will reply, but my explanation is that as you say, T2 was a well-made commercial DVD. For encoding that, they made several passes through the program, to do the best encoding they can. Our DVDRs have to do that on the fly, in one take. Giving them more bits to work with makes it less likely they will screw up.
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post #21 of 38 Old 10-23-2007, 06:10 AM
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Hi guys,

Interesting thread... I have a question I've been wondering about. I have been recording movies on a pio650, using analog cable in LP, since I discovered they turn out pretty good. If I know the movie will contain lots of action scenes, I'll use SP, but for most of the movies I watch, it's mostly talking heads and so forth.

Here's my question: sometimes there'll be a scene where the person turns his head, or moves it a bit, and it will look a bit cartoonish, sort of like one side of the head starts to move and then the other side of the head will follow. I notice that happens more when the scene is darker. I'm curious, what causes that. I would expect LP would cause blurriness or unsharp edges, but this looks kind of weird. Anyone else notice that?
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post #22 of 38 Old 10-23-2007, 08:39 AM
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DVDR3575 Recording Football (hardest sport to record w/good PQ)

I did a football test at 3-hr-LP with my Philips 3575 on ESPN digital HD channel downresd in my analog cable feed. The results were very good, especially the mid-range and closeup shots from sideline, goalpost and booth cameras... they were brilliant at 3-hr-LP!

Long shots from the stadium camera are the hardest for MPEG2 to capture with good PQ. I noticed that ESPN's long shots confined their range to ~30 yards, where some other networks seem to show almost the entire field, and ESPN zooms half-way in or so for runs.

In my recorded game, the 1/32" numbers on the 1" little men had just slightly hairy edges. That PQ degradation is probably unavoidable with LP since you're trying to capture the little men all moving in different directions. MPEG2 is predictive in nature and easily captures predictable movement, like race cars on a track, at a relatively low bit-rate (~2.5Mbps). It does increase bit-rate for major (big) scene elements that change or move unpredictably, but the little men in football long-shots are so small (little objects in BIG stationary picture, till they zoom in) that MPEG2 probably doesn't see a need to boost bit-rate for better PQ.

In my 3-hr-LP test, I set a timer rec. for 7:30-10:30 to cover the scheduled show time, but the 3-hr program missed the last 2:33 of the game (ran over).

When I went to dub, my 3-hr-LP football game, it showed 3966 MB at HIGH speed with disc space at 4424. That means you could fill up the extra MB at the same 3-hr-LP rate with another 13-20 minutes and still have a HS-dubbable game.

So, to cover everything but "sudden death," you could set the timer for 3:30:00 and rec mode for LP, then cut some of the fluff at beginning and end. The ESPN game had 9 min. of pre-game fluff...kickoff didn't start until 9:30 on the record clock...so it should be easy to get down to the 3:13:00-3:20:00 limit just by cutting a couple of commercials. Who knows, some severe cutting might get you down to the 2:09:00 SP mode!?

Anyway, with my Philips 3575 setup, 3-hr-LP works great for a football game on a digital channel when the crew uses HD cameras. Broadcasts shot with SD instead of HD cameras will be pretty obvious by the softer edges in the live pic. These games can produce a much lower-quality recording, so 3-hr-LP might not be adequate for some when the source is basically SD-quality.

One example: I recorded a MNF pre-season game on an SD channel and the field shots looked like "previously recorded" tape while the booth shots were their normal brilliance. Needless to say, the game portion rec. at 3-hr-LP looked pretty bad since it was awful to start with... a very strange occurrence.

SD = Could be Bad, HD/Digital = Usually Very Good.

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Quote:
Originally Posted by kjbawc View Post

Well, hopefully someone here more knowledgeable than I will reply, but my explanation is that as you say, T2 was a well-made commercial DVD. For encoding that, they made several passes through the program, to do the best encoding they can. Our DVDRs have to do that on the fly, in one take. Giving them more bits to work with makes it less likely they will screw up.

I actually think that is a very good explanation -
perhaps explaining why a Qf of 0.26 on the 6hr(SLP) recording despite being in the upper range of "quality" as given by Wikipedia - still looked "imperfect" - I do see motion and edge artifacts -
don't get me wrong, the SLP recording is still pretty good most of the time, and I only see those artifact occassionally - but the fact is I do see them - and those would have been unacceptable if they were on any commercial DVD (hey but what could I expect - it's a 6hour recording!).
On the other hand, in mitigation - I often see faults on the HD signal on my friend's 1080p HDTV - that look far worse than on my SLP(6hr) recordings.

However why LP(3hr) recordings look good is probably because the Qf (quality factor) is actually higher than SP(2hr).

My LP(3hr) sample recorded on a SV2000 WV10D6 according to GSpot -

LP(3hr) 2631 kbps, Qf = 0.520 (bits/pixel)/frame
compared to
SP(2hr) 4339 kbps, Qf = 0.419 (bits/pixel)/frame

How can LP(3hr) possibly have a higher Qf than SP(2hr)?

Easy - on my SV2000 WV10D6 the resolution on LP(3hr) is dropped to CVD 352x480 - so the pixels/frame is about half of DVD 720x480 resolution - therefore Qf which is (bits/pixel)/frame needs only half the bit rate to have the same Qf - and it stands to reason that LP(3Hr) would give closer to 2/3 the SP(2hr) bit rate - ie: greater than half - so the Qf ratio is going to be higher by (2/3)/(1/2) = ~1.33, which is roughly about what I got in my test samples.
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post #24 of 38 Old 10-23-2007, 07:22 PM
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Originally Posted by wabjxo View Post

I was "treated" to a sickening illustration of this at my local Sears, where a very helpful sales lady showed us all the HDTV flat panels and, as we began to discuss PQ, she bravely mentioned that we would probably need to upgrade our cable service to HD or we might be surprised. She said several people have bought their first HDTV flat panel from them, got home, and then complained loudly that the picture was lousy...not at all like in the store.

Well, these people had basic analog cable, so she illustrated for us how that would look at home if we didn't upgrade our basic analog cable. They had Dish satellite signal, so she switched to basic analog type signal, and the picture WAS "disappointing."

Needless to say, since I sorely hate to give a cell phone company a chance to add fees-on-fees ("feefees"), or the tel. co. to do the same, I'm dreading being forced to upgrade my cable service and give them a chance to add some more feefees on my bill...but, apparently, my new flat panel (if I ever get one now) won't do me much good unless I do!

I can't speak for your cable company, but "basic analog cable" here includes all of the OTA-equivalent HDTV channels for no extra cost and with no need for a Comcast cable box. An HDTV equipped with a QAM digital cable tuner will receive these stations. I have tested and proven this at my home any many others. I subscribe to the $14 "Limited Basic" cable package, but I still get all of the local digital channels.

So, I am not sure whether your scenario is the same or not, but I can tell you that I have taken my RV to many parks that provide local cable service and I have no problem receiving the HD channels with my HD/QAM TV in the RV.

I am wondering what you mean by a "bootleg" digital channel.

Besides having the digital HD channels, we also have digital equivalents of the standard analog channels--digitized at the Comcast head end that serves us.

As you might expect, the true HD channels down-rez'd to 720x480 for viewing on a non-HD TV (even older analog TVs) look far better than the same channel content on digitized analog channels. I would think that your digital-tuner DVD recorder would tune in the HD channels and down-rez them to 720x480 for live viewing or recording.

I have yet to find a TV sales person at any store like CC, BB, Sears, even Fry's that really understands this stuff. Some sales folks at Magnolia do understand.

The only reason I see for upgrading to a higher level of cable (analog or digital) is to get more channels than the lower level package.

Please let me know if what I say here is inconsistent with the cable service available to you.

Dave
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post #25 of 38 Old 10-23-2007, 07:37 PM
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What you describe there is something people here in the South talk wistfully about... on their porches... under the giant willow trees lining the path to our plantations.

I subscribe to the lowest TWC Basic Cable, which is 45 all analog channels for $35/month. With my Basic analog cable, I'm also able to receive 6 digital channels they apparently send in the clear, only one of them a local. Thankfully, I get TNT, ESPN HD, and Discovery HD. I call these my "bootleg" channels.

I just got their info on their "Digital Tiers" and for $50 + $7 for one "must-have" box (for only one TV) I can get a whopping 26 additional digital channels... really good ones like the Military Channel, Style, Speed and many other wildly popular channels. For $56 + 7 I can add 19 more digital channels like Fox Soccer, Gospel Music, Fine Living, CMT Pure Country and many more exciting channels.

I can't wait to sign up... or move back to Seattle!
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post #26 of 38 Old 10-23-2007, 08:26 PM
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Quote:
Originally Posted by wabjxo View Post

What you describe there is something people here in the South talk wistfully about... on their porches... under the giant willow trees lining the path to our plantations.

I subscribe to the lowest TWC Basic Cable, which is 45 all analog channels for $35/month. With my Basic analog cable, I'm also able to receive 6 digital channels they apparently send in the clear, only one of them a local. Thankfully, I get TNT, ESPN HD, and Discovery HD. I call these my "bootleg" channels.

I just got their info on their "Digital Tiers" and for $50 + $7 for one "must-have" box (for only one TV) I can get a whopping 26 additional digital channels... really good ones like the Military Channel, Style, Speed and many other wildly popular channels. For $56 + 7 I can add 19 more digital channels like Fox Soccer, Gospel Music, Fine Living, CMT Pure Country and many more exciting channels.

I can't wait to sign up... or move back to Seattle!

Basic cable here is also around $45, but Limited Basic varies by jurisdiction from $9 to $15 (plus tax). But, if you call Comcast and ask about the lowest-cost offering, they will likely NOT tell you about Limited Basic. You have to know enough yourself to ask for it specifically.

Perhaps your town or county or other governmental unit can tell you about low-cost services that are required to be available for the cable compnay to maintain their franchise. OTOH, maybe those requirements are just not there where you live.

I do enjoy reading your posts that cover equipment I want but don't yet own. What I have is often older, but nice, like my Pioneer 520H DVD recorder, which is almost as good as a 640. My CRT RPTV Mits HDTV is 5 years old and still going strong. I am spoiled and watch mostly HDTV, to the point of having to upgrade from the built-in analog 4x3 TV when I bought our used (new-to-us) fifth-wheel trailer earlier this year.

Well, we all enjoy our toys, and we pick the ones we "need" or want the most.

I have a younger friend (former work associate) who converted his craving for toys into his vocation. He has had professional schooling and is now in the digital photography (portraits) and commercial video production business. He has latest and greatest Mac computers, iPhones, still and video HD digital cameras/camcorders, a brand new Dodge diesel truck to haul his gear (my truck is 6 years old), and on and on.

Dave
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post #27 of 38 Old 10-24-2007, 07:22 AM
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Quote:
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Basic cable here is also around $45, but Limited Basic varies by jurisdiction from $9 to $15 (plus tax). But, if you call Comcast and ask about the lowest-cost offering, they will likely NOT tell you about Limited Basic. You have to know enough yourself to ask for it specifically.

Perhaps your town or county or other governmental unit can tell you about low-cost services that are required to be available for the cable compnay to maintain their franchise. OTOH, maybe those requirements are just not there where you live.

I called our town person who USED TO control the sole cable company that serves our town when the cableco raised it rate for the cheapest cable, which I have. I asked if he approved that raise. He said that, thanks to Bill Clinton, he no longer has any say in their rates...a new law or something says they can raise rates as long as they're reasonable, and towns no longer control the rate structure...at least here in the South.

I never did ask the cableco directly for a "limited basic" or similar low-cost option so I think I'll do that. Thanks for mentioning that option.
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post #28 of 38 Old 10-27-2007, 08:56 AM
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I've made two sets of matching samples of the same frame (or almost) recorded on my Panasonic DMR-EH75V at seven different quality levels. These were dubbed from a HD DVR.

Frame #1 has very little motion. The total size of all the samples is about 1.0 MB.

Frame #2 has a lot of motion in part of the picture. The total size is about 0.7 MB.

I also have a description of the procedure that I used to produce these images.

I ended up dubbing the first game of the World Series in LP (4-hour) mode, and the second game in FR mode (3:10 hour). To my eyes (on my 32" LCD), the FR-mode recording is acceptable unless I really want that extra bit of quality, in which case I would go with a two-disc version at 1:30 to 1:40 per disc. The LP-mode recording is noticeably inferior, although not totally awful.

When watching the video on a TV screen, the compression artifacts move around, which makes them more noticeable than on a static image. Also, I think the frame-extraction process smooths things out a bit.
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post #29 of 38 Old 10-27-2007, 04:42 PM
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Quote:
Originally Posted by jtbell View Post

I've made two sets of matching samples of the same frame (or almost) recorded on my Panasonic DMR-EH75V at seven different quality levels. These were dubbed from a HD DVR.

Frame #1 has very little motion. The total size of all the samples is about 1.0 MB.

Frame #2 has a lot of motion in part of the picture. The total size is about 0.7 MB.

You don't say if the frame you picked for repro was a "random" frame or a "key" frame (I-frame) in a MPEG2 Group-of-Pictures (GOP)?
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post #30 of 38 Old 10-28-2007, 12:19 AM
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They're random, that is, I didn't specifically look for key frames. I could try using key frames, because MPEG Streamclip has a command that goes to the nearest key frame. I probably wouldn't be able to get them to match exactly in time because the DVDR recordings started at different time points in the source material.

Would it make a significant difference in the results?
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