Masterizzatore Blu Ray Per M-DISC e BDXL [Archivio]

maurilio968

05-07-2016, 11:10

Io non mi fisserei tanto sugli m-disc bluray.
Piuttosto compra dei bluray HTL ed evita glòi LTH.

Trovi tutto nei link di questo post:

http://www.hwupgrade.it/forum/showpost.php?p=43834764&postcount=1182

inoltre da qui:

http://www.pcworld.com/article/2933478/m-disc-optical-media-reviewed-your-data-good-for-a-thousand-years.html

riporto un commento interessante:

The MDISC test that was performed by the Navy was actually written/concocted by MDISC themselves (Milleniata). The Navy merely "carried out the script"...

If you read the full test, the test appears to have been slightly "cooked" in two ways: 1) the MDISC media were placed into the coolest sections of the chamber; 2) no media was written to the outside edge.

Both of the these are important and significant:

The report indicates that one drawback/difference of the MDISC media is that since it lacks a reflective layer, it gets significantly hotter than other media when subjected to the same conditions. The test showed that the MDISC media, even with the benefit of being in the coldest section of the chamber, were 1 degree warmer than all other discs. This is likely to be a problem with any dual-layer DVD where the two sides are very likely to delaminate - leaving the data inside destroyed.

What the report leaves out is that the use of a phase-change material, rather than an organic dye is not part of the DVD spec - so MDISC are not compliant media. Your own testing showed one downside of this - the inability of the media to be read in *ALL* compliant drives.

Further, the phase-change media is significantly *HEAVIER* than the dye, *AND* this has an impact on the media in real-world-use. Other sources have bought MDISC off-the-shelf and found that the error rates at the outer edges of the disc immediately after writing to them were above the PI8 acceptable max. So - if you fill an MDISC with data, you've likely immediately lost some of the data that you've just written to it.

Its been theorized that the weight of the material at the edge of the disc is significant enough that its warping the disc during rotation and is thus putting it outside the acceptable parameters of the media in operation.

But, lets get to some real issues with MDISC - its not unique. All Blu-Ray BD-R (HTL) use phase change material. MDISC uses a CTeC "cake"; other Blu-Ray use slightly different composition for their "cake", but still involve Te, such as TeOPd.

See these papers/citations:
https://en.wikipedia.org/wiki/Tellurium#cite_note-53
https://en.wikipedia.org/wiki/Tellurium#cite_note-54

MDISC is Blu-Ray certified, but that's because they aren't doing anything unique really - they have a slightly different chemistry to their "cake", but it performs like any other BD-R (HTL) because its using the same principles.

When you figure in the difference in the cost of the media: MDISC 25GB >$5 vs. other BD-R (HTL) 25GB

MDISC was a great idea when all available optical media were using organic dyes that deteriorate over time - but the entire industry knew that. Existing standards couldn't be changed, and with Blu-Ray we have a much better product but the word hasn't gotten out yet.

Personally, I'd recommend either archival quality gold-foil CD-R, or standard Blu-Ray. The top quality archival CD-R has already been shown to be orders of magnitude longer lived in testing than *ANY* DVD (see, NIST, Library of Congress, etc). CD drives are so ubiquitous, and the media work in virtually all of them - there's no compatibility issues to worry about ever. And, Blu-Ray being the successor to, and improvement on DVD - the drives will be newer, around longer, and the standard media have the same benefits at a lower cost.

MDISC have convinced the government, using their own cooked test procedure, that MDISC have an advantage. Even after that, the government recognizes that standard Blu-Ray are just as acceptable. Look at the federally approved Hitachi Digital Preservation Platform: http://www.hdsfed-hdpp.com/resources/HDS-Overview-Brochure-Final.pdf -- MDISC (because of the successful marketing campaign), and Blu-Ray (because its an equivalent product).

MDISC is mostly marketing hype.