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Discussion Starter · #1 ·
After lots of searches and thread reading, I know that the E20, E30,

and HS2 have a problem recording an incorrect black level when using

DVD-R discs. It also seems to be the case that the E30 and HS2 record

with an incorrect black level even if using DVD-RAM discs.


But a couple of threads from way back indicate that the E20 does not

have a black level problem if recording to DVD-RAM discs. Is that actually

true? It seems strange to me that the E20 would be free of this problem

when the two succeeding models have it.


I have an E20, and when I play the VRO files on my computer (with

calibrated monitor), I can't see any obvious problems. I use MPEG2VCR,

WinDVD, WMP, and DVDWS to view these files. Since MPEG2VCR seems

to play them with a slightly lighter setting than the other three programs, I can't really form any concrete conclusions.


I don't have any non-Pany DVD players, and don't have easy access to any

at friends' houses, so I'm hoping I can get some definitive answers about

this issue in this forum.


yrabb
 

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Guess I'm not as much of a videophile/audiophile/geek as I thought, or perhaps I need to clean my glasses a little more often, because I could not notice any black level bug with recordings done on my DMR-E30 and played back on my samsung c621. Both machines read my Samsung BeAll DVD-R and played back beautifully, and no notice that one was darker or lighter than the other (or the original for that matter)


What a wonderful little machine! :D


Recorded old [email protected] condition Wedding Camcorder footage to DVD-R in SP mode and it looks great. And recorded "Spirit" off the dish last night for the wifie in FR mode (1:27) and I could not tell the difference between the DVD-R and the original. I kept waiting for the macro blocks or the mosquito noise but it wasn't there. 2 DVDs done and I'm loving this thing!


Originally I wanted the HS2 (with the HDD) but there's no way I could justify more than doubling the cost just for the hard drive features ($799 vs. $366) Just buy a few doublesided ram cartridges.


As for the Darkness bug, I don't have an oscilloscope or a Huge Plasma display, just a wee 36" RCA and DAMN THE DMR-E30 LOOKS GOOD!


I say pick up an E-30 while they're unbelievably cheap, and let your eyes judge for themselves.
 

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You probably won't see any mosquito noise or macro blocking in most recordings as the Pannys back off resolution in order to get better compression. The only times I've ever noticed any compression artifacts were at very low bitrate (ie. long record times, LP) with fast moving action. In this case an F1 race.
 

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Quote:
Originally posted by yrrab


I don't have any non-Pany DVD players, and don't have easy access to any

at friends' houses, so I'm hoping I can get some definitive answers about

this issue in this forum.


yrabb
You won't get any definitive answers here. There is no "bug". Panasonic made a specifications decision for NTSC units. Some people have made an issue out of the fact that Panasonic strayed from a reference standard. For practical viewing, the majority of users are satisfied with the results. It's a theoretical argument that seems to have targeted Panasonic, despite the fact that other manufacturers made the same kind of decisions.
 

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Quote:
Originally posted by mrwilson
The only other manufacturers that 'made the same kind of decision' are the ones OEM Panasonic hardware.
Not quite. During the "bug" threads, it was raised in this forum that JVC had made the same decision with their HM-DH30000U digital VCR:


Quotation from Widescreen Review evaluation of unit:


"When making digital recordings, the 7.5 IRE black level setup that is standard on NTSC analog signals should be removed prior to recording, but the HM-DH30000U does not perform that function. This results in non-standard digital levels when recording from analog signals. As a consequence, the TV display must be calibrated differently for recordings made from digital signals than for recordings made from analog signals. This must also be considered when transferring digital recordings across the i.Link interface."


Chris Meyer's (DV magazine) article on luminance ranges summarizes:


"In analog video, the electrical reference for white is generally defined as 100 IRE, using near-identical electrical levels regardless of format. The electrical reference for black depends on what video format you are using and even what country you are in. PAL and the Japanese version of NTSC always use 0 IRE to define black. Composite NTSC video in North America uses an electrical value of 7.5 IRE, which is sometimes referred to as setup. Component video in North America can use either 0 or 7.5 IRE for black. In our experience, 7.5 is more common".
 

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All the Panasonic recorders prior to the E50 make the assumption that the black level of the source is 0 IRE whether recording to -RAM or -R.


If you play back a recording made by one of these on a player which uses a 0 IRE black level, the output should be the same as the original source. If you play it on a player set to 7.5 IRE black level the output black level will be a few IRE higher than the original.


There are other manufacturers who chose to assume 0 IRE for black input level, though so far Toshiba is the only other DVD recorder manufacturer (and they use Panasonic components.) In addition to JVC's D-VHS recorder, Sony assumes 0 IRE black level with their Digital8 cameras analog inputs. Strangely Sony chose 7.5 IRE output for most of their DVD players, with no option to set them for 0 IRE.


I have to commend Panasonic USA in coming up with a solution in their new models which allows the user to set the black level on the input and allow them to decide which standard to use (if they care to.) Apparently that Widescreen Review article had some influence in their decision.
 

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Quote:
If you play back a recording made by one of these on a player which uses a 0 IRE black level, the output should be the same as the original source. If you play it on a player set to 7.5 IRE black level the output black level will be a few IRE higher than the original.
According to the test VJ did earlier this year it was an additional 5.5 IRE. Quite a bit.
 

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Quote:
If you play back a recording made by one of these on a player which uses a 0 IRE black level, the output should be the same as the original source. If you play it on a player set to 7.5 IRE black level the output black level will be a few IRE higher than the original.
According to the test VJ did earlier this year it was an additional 5.5 IRE. Quite a bit.
 

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Discussion Starter · #11 ·
Quote:
Originally posted by dgb
All the Panasonic recorders prior to the E50 make the assumption that the black level of the source is 0 IRE whether recording to -RAM or -R.


If you play back a recording made by one of these on a player which uses a 0 IRE black level, the output should be the same as the original source. If you play it on a player set to 7.5 IRE black level the output black level will be a few IRE higher than the original.

So, if you record with an E50 using the new "darker" input setting, would

the resulting video play too "dark" on a player that outputs at 0 IRE? :confused:
 

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Quote:
So, if you record with an E50 using the new "darker" input setting, would the resulting video play too "dark" on a player that outputs at 0 IRE?
No, it'll play back at the correct level. I really wish they would have called it 'Normal' instead of darker. The lighter selection is aptly named. ;)
 

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Hello :)


Yes I know this is an old thread but I've recently been considering getting a Canopus ADVC-100 which is a stand alone box that does analog to DV conversion. I've been reading the forums over at DVDRHELP and everybody there raves about how great this unit is at converting analog video (with locked audio support) to the DV format. It then transfers it to the computer using the firewire port. Basically works like a DV camera with analog pass thru. The opinion is that this is the best way to capture A/V to a computer (as opposed to using an analog TV tuner type card or the video in of a video card such as the ATI AIW design or the Nvidia VIVO design).


Anyways ... the Canopus ADVC-100 has selectable 0.0 IRE or 7.5 IRE settings. If I am reading this thread correctly and since I live in the USA I should use the 7.5 IRE setting when recording a video source such as VHS, LaserDisc, cable or any US NTSC video source. Now the final output of this capture will be the creation of a DVD-R disc. So I want to make sure that I have the setting proper so that my DVD will look normal and thus avoid the black-level "bug" that plagues the early model Panny stand alone DVD recorders. BUT ... don't some DVD players have selectable output (user choice of either 0.0 or 7.5 IRE). If the DVD player you are using doesn't have any selection and is a US model then what is the normal output setting ... 7.5 IRE? Which setting should I be using for the output of the DVD player and does it make any difference if the source is a home-made DVD-R vs a commercial studio/factory made DVD disc?


Also the last post (above mine) is confusing me. It seems to contradict how I understand the process to work. Apparently the Panny E-50 has two settings but they are called "darker" and "lighter". Which is which in regards to 0.0 IRE and 7.5 IRE?


I'm totally confused now hehehe
 

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You are right that you would set the ADVC-100 to 7.5 IRE for most sources. This will translate 7.5 IRE to 16 digital, which is the correct value for black in the digital domain.


For a source with 0 IRE black level you would set the ADVC-100 to 0 IRE, and black would again be encoded at 16 digital.


Where the earlier Panasonic recorders go wrong is in assuming that all sources have 0 IRE black level. You can do this too if you set the ADVC-100 to 0 IRE and input a source with 7.5 IRE, black is encoded at 34 digital. This results output of a 7.5 IRE signal on a player set to 0 IRE, and something around 12 IRE on a player set for 7.5 IRE.


There is a post by videojanitor where he tests a DMR-E50, if I remember correctly the darker setting corresponds to the 0 IRE setting on the Canopus, while lighter corresponds to the 7.5 IRE setting.


The ADVC-100 was one of the devices which dr1394 tested for us, and it behaves correctly if it is set to match the black level.


The player setting doesn't really matter. As long as the source is encoded with black at 16 digital, the output will be at the proper black level on a display calibrated to match the black level of the player.


David
 

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In digital world 0 IRE is 16. Digital video recording recorded at any other level is out of spec. 7.5 IRE setup should only be added on playback.
 

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Hello :)


A big thanks to dgb for clearing that up for me, especially in regard to the IRE setting for the output of the playback DVD player.


However, it would seem that CKNA disagrees?


Need we drag this out further? hehehe
 

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Tim,


Unfortunately, the MPEG data recorded to the DVD-R is encoded using the wrong setup, so it doesn't matter where the finalization process is carried out.


David
 

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David,


bummer, but thanks for resolving the issue for me. I suspected as much, but hoped it might have been otherwise. Ah well.


At least for those discs I'm adding to my Sony 875p changer I can use the 300 picture memories to drop the luma down for each disc, and let the changer keep track of it.


For those going out to others, the situation is less tidy. Where critical, would it be possible to suck the data off the DVD-R on my PC with a -321 DVD-RAM drive, and run it through something to adjust the setup, then burn it to a new disc?


- Tim
 

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I believe there's going to be a re-encoding stage involved no matter what. The simplest solution, since it sounds like you're going to buy a recorder without the bug, is just to play the original on a player set to 0 IRE and record onto another disk.


Maybe there's a software solution, but the processing, encoding, and burning will probably take at least as long and may not produce significantly better results.


David
 
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