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Discussion Starter · #1 ·
I need some help understanding exactly how this works...


I recorded a three hour show to the hard drive using the FR mode so it would use the highest possible disk space. This seemed to work fine. My question is, when I went to dub this to a DVD-R disc, it again gave me the option of what recording quality to use. I was under the impression it would dub whatever quality I had recorded onto the hard drive, dumping the raw digital data.


Is there another D/A to A/D conversion going on? If so, is there anyway to tell it to dump the exact data recorded to the hard drive?


I guess I would have been better off recording to the HDD at the XP quality, before compressing it to fit onto a DVD-R.


Any help would be great!


Thanks!


EJ
 

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You are right about recording at XP to HDD then FR to DVD-R BUT, I did this recently and on playback it was very jerky whereas when I recorded a 3 hour section using LP there was no problem. Like you I assumed that FR would record slighly better quality than LP as it was spreading the video of more space. I am worried by this replay of FR as anyone any experience of this.

The other thing that mystifies me is the Generation 4, and 1x, 2x when purchasing DVD-R whats this all about and is the DMR-HS2 compatible with these, where do I find out? For info I am using Bulkpack Generation 4 2x disks.

Chris
 

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it's not another D/A A/D conversion, but another encoding.


If you record at the same quality, it would probably get you only a small reduction in picture quality over the original recording.


Sometime, you might want to record a high quality HDD recording to a slightly lower quality DVD recording. It's a good option.
 

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Quote:
Originally posted by EJ
I need some help understanding exactly how this works...

I recorded a three hour show to the hard drive using the FR mode so it would use the highest possible disk space.

EJ
I think using FR to the HDD for a three hour program was the first mistake. FR will only see a maximum size of 4.7 gb when employed on the HDD. Therefore, you actually lost more quality by using FR than if you had simply recorded the entire 3 hours to the HDD at XP.
 

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Discussion Starter · #5 ·
So am I correct in assuming that there is no way to go from HDD to DVD-R or DVD-RAM without another re-encoding?


If I know it's going to be a permanent copy, would I be better off going right to DVD-R and skipping the HDD altogether?


If this is the case, I am somewhat surprised that a direct transfer is not possible.


EJ
 

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Quote:
Originally posted by EJ
I need some help understanding exactly how this works...


I recorded a three hour show to the hard drive using the FR mode so it would use the highest possible disk space. This seemed to work fine. My question is, when I went to dub this to a DVD-R disc, it again gave me the option of what recording quality to use. I was under the impression it would dub whatever quality I had recorded onto the hard drive, dumping the raw digital data.


Is there another D/A to A/D conversion going on? If so, is there anyway to tell it to dump the exact data recorded to the hard drive?


I guess I would have been better off recording to the HDD at the XP quality, before compressing it to fit onto a DVD-R.


Any help would be great!


Thanks!


EJ


Hi EJ,


If you record from HD to DVD-R, there will always be a D/A to A/D conversion. But the average user can NOT see the loss in image quality!


If you record to DVD-RAM with the SAME bitrate(SP>SP or XP>XP), there is NO conversion taking place. In that case you get a 100% digital copy



The best way to dub your recordings to DVD-R is this (IMHO)

Before doing anything:

Set in the SETUP menu to !!!


1. record to the HD:

Examples:

- 1,5 hour program: record in XP mode

- 3 hour program: record in XP mode

- 4 hour program: record in XP or SP mode

(see below why)

2. Remove commercials etc.

3. Divide your program if longer than 2 hours:

Examples:

- 3 hour program: divide in two 1,5 hour pieces. When you then record to DVD-R in FR mode you will get a higher bitrate than SP so the quality will be great! >> In this way you will get the optimum bitrate per DVD-R

- 4 hour program: divide in two 2 hour pieces. When recording to DVD-R you will get SP resolution even when using FR mode.


(I hope you get my point?)

4. dub from HD to DVD-R in FR mode


ATTENTION:

If you copy more than 2 hours and 20 minutes onto DVD-R, you will get a recording in LP mode (half the DVD resolution!)

If you like that, buy a cheap VHS recorder ;)


I spent a lot of time reading this forum and learning a lot from experienced user like vferrari and many others.


READ BELOW FOR DETAILED INFORMATION!


Have fun with your HS2!

Erik




http://www.avsforum.com/avs-vb/showt...hreadid=179838
vferrari wrote:


Here is a summary of the recording modes and the resultant resolutions:


XP: 708X480, 1 hr. per 4.7 GB

SP: 708X480, 2 hr. per 4.7 GB (avg. bitrate about half that of XP)

!! LP: 352X480, 4 hr. per 4.7 GB

!! EP: 352X240, 6 hr. per 4.7 GB

When using the FR mode, the shift to the LP resolution doesn't occur unless the recording is longer than about 2:20 min in length. So with FR recordings of programs slightly longer than 2 hr, you can retain the 704x480 resolution with a slightly lower avg bitrate than SP (probably not very noticeable). If you want to avoid the loss in resolution to LP 352X480, you need to keep your FR recordings less than 2:20 in length. Furthermore, you should make sure the Hybrid VBR Mode menu setting is set to OFF and not AUTO, otherwise, you might get suprise automatic resolution "downshifts" during XP, SP, and FR recordings.


Vic


http://www.avsforum.com/avs-vb/showt...hreadid=196129
warp9 wrote:


I bought an HS2 unit a couple months ago and have been extremely pleased with it compared to the S-VHS recordings I formerly made for archiving my fav shows. I truly can barely tell any degradation from the original broadcast when recording in the highest XP quality setting (8.5 hours total time on the Hard Drive, 1 hour per DVD-RAM or DVD-R disc).


The standard SP mode (17 hours on HD, 2 hours per disc) does show a very few blockiness artifacts on fast scenes, but it's barely noticeable unless you concentrate and are fairly close to the screen. Both the SP and XP modes have the same DVD-quality resolution (720x480) but the XP uses a higher bit rate for better moving scenes display. When you get into the LP (4 hr/disc) and EP (6 hr/disc) modes the video rez gets cut in half or worse and I really don't like reverting back to their S-VHS and VHS quality levels, respectively.

If you stay below 2 hours and 20 minutes for transfer to a DVD-R or DVD-RAM disc, you'll get the SP's hi-rez quality when you use the FR mode (Flexible Recording) that lets you squeeze the selection to fit in a given time on DVD-R/RAM discs or to the hard drive. For 4 hours, you'd either need to split into two segments when you program the recording, and I'd strongly suggest that method for the boost in sound and video quality, or else shift over to the LP/EP modes at S-VHS/VHS quality. I prefer to use sequenced one or two hour segemnts in XP or SP mode for marathon days of show re-runs rather than use one big segment when you're going to dub over to discs.


I ALWAYS record in XP mode to the hard drive for later transfer to discs. With editing out commercials, one hour shows are 41 or 42 minutes and I fit 3 onto a single disc with great quality results in FR mode that gives the SP resolution at DVD quality. The HS2's tuner is really excellent compared to my other units as well as the video capture card on my PC. I use my PC's ATI all in wonder card to program up a week's worth of shows as a back-up to the HS2 just in case. I forgot to program the HS2 for two shows so far and the PC backup approach let me still catch the shows.


BTW, it's best to use Shorten Segment command on the hard drive Navigator menu to cut out commercials. You can use the CM key under the pull down lid on the remote to QUICKLY skip thru your videos to select the commercial segments to erase.


I've been using generic brand "Lead Data" discs in spndiles of 50 at 93 cents each after shipping from dvdroutlet.com. I've burned about 50 on both my HS2 and my PC's DVD-R burner without any problems at all. The HS2 discs have played in several of my friends' consumer DVD players, although my PC burned ones don't play in a couple of old 1st generation Toshiba players. I use slimline CD-jewel cases to store them in and some Fellowe's MediaFace2 software to make color labels for the slimline cases (25 cents per label and less than 20 cents each in bulk for the cd cases).
 

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Quote:
Originally posted by EDR
If you record from HD to DVD-R, there will always be a D/A to A/D conversion.
No offense, but this seems weird. Are you sure?
 

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Quote:
Originally posted by David Hwang
No offense, but this seems weird. Are you sure?
Non taken ;)


Well, I read it somewhere in this forum from people who seems to know what they are talking about...


I will search the thread for you tomorrow, it's now 3:15 am here: bedtime! :eek:


Bye,

Erik
 

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Quote:
Originally posted by EDR


ATTENTION:

If you copy more than 2 hours and 20 minutes onto DVD-R, you will get a recording in LP mode (half the DVD resolution!)

If you like that, buy a cheap VHS recorder ;)
Even with the smiley, that's pretty rude.


I want a DVD recorder to have more durable media and be able to edit out commercials prior to burning to DVD-R..

However, I know I'm going to play with all of the various recording qualities and pick the one that's just barely above what I can stand. (For example, for timeshifting, I record ona Tivo at the lowest quality.. For things I'm going to dub off, I usually do one step above the bottom.. If/when I add another hard drive, I'll probably move both of those up ONE notch.)


You don't have to be a video snob.
 

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I haven't seen the results of any tests of whether a dub which doesn't involve a bitrate change (e.g., SP HDD to SP DVD-R) is lossless or not. I suppose you'd have to compare the same frame on DVD-RAM (which does dub without re-encoding in high speed mode) and on DVD-R and look for signs of re-encoding.


Don't know why they'd go D/A - A/D rather than D/D. Probably because it plays in real time, it's natural to assume that it plays back and records the output. I *suspect* the dub is digital and they do it in real time simply because then they don't need a faster processor than is needed to handle edit points during regular playback.


David
 

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Quote:
I *suspect* the dub is digital and they do it in real time simply because then they don't need a faster processor than is needed to handle edit points during regular playback.
I agree that the DVD-R D>A>D theory is speculation based on circumstantial evidence (i.e., real time dubs only, and HS2 seems to "treat" the source for a DVD-R dub (HDD) as if it were an analog input). However, if what you suspect is true is actually true, then why do you suppose they went to the effort to differentiate between DVD-RAM and DVD-R when providing the capability to do high speed dubs?


Vic
 

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Quote:
The reason is simple: the DVD-R writer they put in HS2 is 1x only.
Though possibly true, it doesn't make sense that all dubs would be restricted to real time. Real time does not equal 1x. Maybe a 1 Hour XP dub would still take an hour (vice half hour in DVD-RAM high speed mode) on a 1x writer, but why couldn't a 2 hour SP, 4 hour LP, or 6 hour EP which all contain the same amount of digital data (~4.4 GB) all be dubbed in one hour also if it was just a straight data transfer at 1x? Why bother "throttling" the dub digital data rate down to "real time" for the lower quality record modes?


Vic
 

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>However, if what you suspect is true is actually true, then why do you suppose they went to the effort to differentiate between DVD-RAM and DVD-R when providing the capability to do high speed dubs?
 

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Quote:
The RD-X2 has a 1x writer too, but it writes a 6 hour EP recording in 1.5 hours (0.67x), while the HS2 takes 6 hours (0.16x)
David,


Yeah. That's my point. If its a pure data transfer thing and the limiting task from a data processing standpoint is processing the edit points, why real time dubs for all record modes (see above - our posts may have "crossed in the mail") vs. a fixed data rate?


Maybe you can ask the Panny engineers about this one, once they finally contact you about the black level issue. We should get an answer about the time they release the HS3. :)


Thx,

Vic
 

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Quote:
Originally posted by vferrari
Why bother "throttling" the dub digital data rate down to "real time" for the lower quality record modes?
Possibly they figure people are used to VHS and won't mind. If the unit is going to be unusable for 90 minutes or so, perhaps they figure they may as well just play in real time for all modes and let the consumer watch it while it dubs.


If there is degradation of an XP to XP or similar dub, it would show that re-encoding was going on.


David
 

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Don't know that Bob at Panasonic knows much about the digital side of these recorders, but he has been very helpful and quick in responding to my questions once he saw there might be something to the black level problem we were seeing. When he does get back to me on the black level issue, I will try and remember to ask if he happens to know the answer on this.


David
 

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Quote:
Possibly they figure people are used to VHS and won't mind. If the unit is going to be unusable for 90 minutes or so, perhaps they figure they may as well just play in real time for all modes and let the consumer watch it while it dubs.
Good point. At 1x though, that would tie up the unit for about an hour vice 90 min, right? Same difference in any event. A 30 minute high speed DVD-RAM dub with no video is bearable but a 1 hour+ "high speed dub" to DVD-R might be a different matter. Personally, however, I'd take the 1 hour DVD-R dub for all modes (except of course transcoding) for the time savings and peace of mind knowing I'm getting a straight digital dub (other than converting the vro DVD-VR file structure to vob DVD-Video).


Thanks,

Vic
 

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Why is DVD-R dubbed in real time?


My guess is that Panasonic is biased towards the DVD-RAM format, thus the DVD-RAM is emphasized more. They only added -R for compatibility with existing DVD players, but they really want consumers to use the RAM disc 99% of the time.


Didn't PanasonicBob say that their DVD recorders are designed for home use and that most customers record and plays the DVD on the same unit?


That, to me, means Panasonic believes most owners use DVD-RAM discs for everyday use. Why else would you use a DVD-R if you're gonna be playing the it on the same unit when a DVD-RAM disc would make more sense?


Again, that's just my guess.
 

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There's a huge difference in the price of DVD-R blanks and DVD RAM, in fact that's one thing that really bugs me about my HS2 - the fact that it is so expensive to run with the best media! In comparison the Philips rewirtable blanks are dirt cheap - down under the Philips rewritables are $15 compared to around $40 for a blank DVD RAM...

If Pana want DVD RAM to succeed then they had better do something about this anomoly - fast. As soon as Philips release a recorder with a HDD then Pana have lost any advantages they have...
 
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