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90min MULTIDISC
This unusual amount of storage capacity is made possible by the combination of the two known methods used so far to raise the capacity. It involves first moving the tracks closer together, as is done with 80 minutes blanks. But here the track pitch change is slightly out of current specification. Second kind of approach is the so-called method of 'overburning' which uses the full capacity of the media beyond the given specifications, giving you an additional 2 to 4 minutes. Both methods used together will give you blanks of exceptional length, which still have to be 'overburned'. This is due to the fact that in the ATIP (Absolute Time In Pre-groove) of the blank such as 80 minute media a maximum recording length of 79:59 minutes is specified - regardless of what actual capacity the blank has. The recording software will read and use the information about the media from this ATIP. If it tells the software that there are only 80 minutes available the only way to use the real capacity is 'overburning' which was until now used in cases where one wanted to squeeze a little more information onto a 74 minute blank. CD-R 90 ATIP cannot be specified like 89:59.74 because for interpreting of minutes are 7 bits available only. Minutes are in hexadecimal code. Let's have an example. For 89 minutes, 89 hex a binary is 1000 1000. We need 8 bits for such a hex number. But as stated before there are 7 bits only. It causes the most significant bit MSB will be truncated and the binary is look like 000 1001. It means 9 hex, 9 minutes and ATIP time is 9:59. As the ATIP is so short a using method "overburning" is necessary. These two facts should be kept in mind in case you want to use the new 90-minute media. Working with both CD-Rs of more than 650 MB and the 'overburning' method require a compatible recorder as well as the right recording software. In terms of software we recommend NERO BURNING ROM from Ahead Software. Also is possible to use CEQUADRAT WINONCD version 3.6 or 3.7 and CDRWIN from GOLDEN HAWK Technology. In case you want to use recording software of other manufacturers we recommend that you contact their support for more information...