EH59/60 Firmware for Black Levels? - AVS Forum | Home Theater Discussions And Reviews
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post #1 of 8 Old 01-25-2020, 07:00 PM - Thread Starter
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Question EH59/60 Firmware for Black Levels?

I’ve got a new EH59 or EH60 (I think, but it’s stowed away in a safe place as an eventual backup for my EH55). My model is the 360 Gb model, I’m fairly sure and I remember I’d been advised that the black levels were low, an equipment design flaw. I suspect I’ll live with this fault, but I wonder if Panasonic had ever issued any kind of firmware update that might have addressed the black level problem and/or if there are any other fixes or modifications that might mitigate this issue.
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post #2 of 8 Old 01-25-2020, 09:21 PM
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After the EH55, no more IRE 7.5 DVD recorders were made by Panasonic.

Its not a design flaw.

Its compliance with an International standard that North America did not participate in.

Panasonic would have no reason to issue a "fix" because there was nothing to fix.

The problem is (two fold).

1) The Black level for IRE 7.5 is deliberately Stepped Up, above absolute Zero voltage to distinguish it from Sync level. In the early days on B&W television in the United States it was hard to figure out Black level from Sync level, so they manually separated them (in the United States.. and by association the North America "NTSC standard") so the electronics could be made simpler in early TV sets. As television became available around the world after WWII the circuits were more advanced so they did not need this separation.

2) It also "compressed" the available room for different black to white levels.. so North American "Setup" reduced the available luminosity levels.. think of it as a paler or less contrasty picture. And it remained that way until February 2009 when it was discontinued.

After the EH55 (and there were models of the EH55 that were International) all Panasonic DVD recorders assumed Black was IRE 0 (zero) and had the "full" range of luminosity.. so the picture was "richer" or more accurate.

Using an International EH58 or EH59 for example will assume the television signal, or signal from a VHS tape has Black at IRE 0, not 7.5, so the signal when played back will look "gray" because its calibrated so that "black" only appears on screen when the signal is at IRE 0.. because North American signals "never" produce or record Black as "zero" it always looks like the blackest black on screen in a program is always brighter than black.. and the whitest white at the top of the range is "squished" and blown out at the top.

Worse it gets complicated with actual DVD recordings to a DVD disc.

The DVD format assumes the North American "Setup" or IRE 7.5 base is "Removed" during recording, and turned back into an International Standard for DVD-video, which always starts at IRE 0. This removal process for a North American recorder works as designed. But an International recorder, does not attempt to "remove" this IRE 7.5 before recording it to disc. Not only is the signal starting out as a compressed "gray" but when played back on the same recorder into a North American TV.. it does not add back in the IRE 7.5 "setup" instead it plays it starting out at IRE 0.. so Black is rammed downwards, and the white level is pulled down.. but it was crushed during recording.. remember the "blown highlights?".. so it just looks all wrong.

There isn't a firmware fix, there isn't a hardware fix "exactly".

What has to be done is the North American IRE 7.5 setup level has to be removed, and then the signal "stretched" to fill the entire IRE range, and the upper White levels pulled down to make sure they aren't crushed against the ceiling. So its a two-part process.

A simple "Proc-amp" can do this.. but its a non-linear process.

1) Its has to be done in the analog domain, before the signal is submitted to the recorder

2) Its best done using a Waveform monitor to make adjustments on the Proc-amp, Brightness, and Contrast controls to "balance" the levels and avoid clipping at either end.. black levels and white levels.

People have tended to do this "subjectively" or "by their own personal tastes".. but its hard to reproduce that way.

Other people have acquired a few Proc-amps that have a built-in bar graph "Level" meter, that mostly alerts them when the blacks are too black, or whites are too white.. without requiring an actual Waveform monitor. Essentially they only light up on either end when broadcast standard levels are exceeded.. and in that way are rather like VU meters in audio production equipment.

Its been "hypothesized" that a simple AV to HDMI (box) and HDMI to AV (box) converter.. might.. strip out the IRE setup and "forget" to put it back in when converting back into AV.. but its never been pursued or proven to work. You would certainly incur some possible degradation in the conversion process.. and it wouldn't be as good as a Proc-amp.. but it should only cost about 40 usd.

Its also been "hypothesized" you could compensate by making a recording to DVD or exporting the raw MPEG2 from the recorder and putting it in a Non-Linear Editor program, like the Full SONY Vegas program which has "software Waveform and Vector" scopes.. and a software Proc-amp. But you would still incur losses from the initial conversion from analog to digital.. the levels would still be compressed, even fixing the IRE problem and stretching it back out.. you can't put back in actual video information that is no longer there.. its gone forever.. it just wouldn't look weird when played back anymore.. just look more "flattened" or "paler" than corresponding recordings from a Region 2 or any other International source with full IRE dynamic range.

This entire (issue) was addressed by Toshiba when they entered the North American market with their RD-XS series of recorders. The first generation, RD-X2, RD-XS32, RD-XS52, RD-KX50 (spain/costco) models all defaulted to IRE 0 and experienced this problem.

The next generation, RD-XS34, RD-XS54 received an additional menu option to "enhance" dynamic range, or turn it off.. which basically performed the compensation automatically.

Toshiba sold the same models with slightly different model numbers in Japan first, which is an IRE 0 country.. and had to refactor their equipment to work in the North American markets.. which included the United States and Canada.. so Canadian models of the EH55 also work the same way as the EH55 models made for the US market.. but the International EH55 model does not work the same way.. it defaults to IRE 0.

So its not so much a design flaw.. as a unique market "accommodation".. there will never be a "fix" for the International models.. because Panasonic never designed them to work in the North American market, they never sold those models in the North American market and have no plans to ever "fix" them.

Last edited by jwillis84; 01-25-2020 at 09:43 PM.
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post #3 of 8 Old 01-25-2020, 10:50 PM - Thread Starter
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Thanks for this solid, well-researched information and so I’ll not plan on my EH 59 or 60 as a backup when either my EH75 or EH55 fails. I hardly have the technical knowledge or skills to make the sort of component adjustments you’ve noted. I’m wondering if now I should do some research about selling the recorder somehow in the international market because Canada would also not be an appropriate target market. If not, there may one day (and probably is somewhere now) be a home AV museum much like the several computer museums in the country to which I can donate a useless device.
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post #4 of 8 Old 01-26-2020, 03:12 AM
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Quote:
Originally Posted by jwillis84 View Post
Its not a design flaw.
Sorry jwillis84 but actually it is a design flaw. If the recorder is supposed to be an international NTSC//PAL recorder player than it should include a 0 IRE as well as a 7.5 IRE set up setting at the analog I/O. In fact even my NTSC only player/recorder includes settings for 0 IRE and 7.5 IRE at the input and output analog lines.
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post #5 of 8 Old 01-26-2020, 05:41 AM
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I'd have to agree with Super Eye that since the international Panasonics have the NTSC setting they should really have come with a +7.5 IRE setting because AFAIK no NTSC country ran with 0 IRE, although it's possible Japan did? If that's the case and since Japan was basically where DVDRs were designed, that might explain why Panasonics used 0 IRE. Still, Japanese companies like Toshiba learned their lesson actually so did Panasonic as their early NTSC only machines also had what at the time was referred to as a black level bug.
Jim, no international EH-60 AFAIK, although the EH-60 was an upgraded model for the '05 EH-50, you have an EH-69 which is the upgraded EH-59, Panasonics last international HDD DVDR AFAIK.
I Personally have several EH-59s and record with them frequently but only from select DVD players that feature a darker setting to feed the EH-59s line input. In this respect, the EH-59 works great and I end up with a proper spec DVD playable on any standard DVD player. Note I know of no other common device that has this simple darker setting, no VCRs or STBs, not even something like a Tivo. Because of this, I delegate my EH-59s to simply making analog copies of select DVDs that I'm not able to copy using my PC.
Too bad as the international Panasonics, particularly the EH-59 and EH-69 were IMO the pinnacles of DVDRs for Panasonic, with the EH-59/75v being the Pinnacle of N. American NTSC DVDRs.
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post #6 of 8 Old 01-26-2020, 10:06 AM - Thread Starter
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Jjeff,

Thanks for the additional info (although, as an oldster, I have no idea what AFAIK means). Unfortunately, I use my EH75 and 55 solely for recording cable “broadcasts” emanating from my Motorola STB or the SSTB’s saved DVR recordings, not from SD or BD discs, so I’m sure that my STB (the model just before the Infinity box with the “cloud” DVR component) Cannot be adjusted.
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post #7 of 8 Old 01-26-2020, 11:33 AM
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^^^ AFAIK=As Far As I Know
I try to not use too many acronyms but I do like AFAIK as it saves typing it all out I've noticed the Brits like AFAIR which I assume=As Far As I Recall
I also like to use FWIW=For What It's Worth when appropriate and of course IMO for In My Opinion.
No in your case the international Panasonics might not be too useful, if you are particular about black levels, which I personally am. A while ago people were talking about making an external device to lower the black level for feeding international Panasonic DVDRs a proper spec signal but it didn't seem to go anywhere. I believe Logic Design(the maker of the Video Filter) was looking into it but as probably not a lot of people are in the need of such a device, there might not be much call for it and therefor not worth his time.
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post #8 of 8 Old 04-25-2020, 02:06 PM - Thread Starter
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Quote:
Originally Posted by Jim Mohundro View Post
I’ve got a new EH59 or EH60 (I think, but it’s stowed away in a safe place as an eventual backup for my EH55). My model is the 360 Gb model, I’m fairly sure and I remember I’d been advised that the black levels were low, an equipment design flaw. I suspect I’ll live with this fault, but I wonder if Panasonic had ever issued any kind of firmware update that might have addressed the black level problem and/or if there are any other fixes or modifications that might mitigate this issue.
Well, I’m going to reopen but modify my query based on the answers below but a changed emphasis. Because I’m an instructor in historic films, I really only need the recording capabilities of my H-69 for black and white films, almost all of which are most likely found on Turner Classic Movies, so the issue of black levels and brightness levels may be less relevant with no color programming involved. I very rarely record color films, even preferring to purchase DVDs where available.

So, if, as I’ve discussed on the display forum, I’m on the cusp (only currently prevented by the virus) of purchasing (probably) a Sony 900X to replace my venerable (2008) 42” Panasonic plasma display which, with, so far, surprising revivals, seems always to have honorably completed its useful life, maybe my EH69 will see me through my film collecting activities.

For the few who might wonder, in my small home space limitations (and the home’s built-in cabinetry) limited my screen size to42” in 2008 but the same space will probably just allow me to move up to a 49” display because of the current slim bezel designs.

I invite any comments on the black level issue as it potentially would affect black and white film recording with the EH69 (my EH55 and EH75 work fine for this purpose).
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