| Q: |
What is the difference between a CD-R and a CD-ROM? |
| A: |
A CD-R is manufactured as a blank disc and the data is written at a later stage using your CD writer. The data is held within a special dye layer which is burned using a laser to create 'pits' and 'lands' which are read by your CD drive and converted to digital
1s and 0s. A CD-ROM is manufactured with the data already on it - the pits and lands are pressed into the polycarbonate base using a 'stamper'. Besides the physical difference, a CD-R is more susceptible to light (the dye needs to be, since it has to be altered
by laser light) so as long as they are handled and stored correctly, a CD-R should behave exactly like a CD-ROM. Just don't store them on the parcel shelf in your car! |
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| Q: |
How long does it take to copy a CD-R? |
| A: |
Of course this depends upon the amount of data being copied and the speed of drive that you're using. We use a range of drives with different speeds from 16X to 52X, which makes the approximate time of recording a full 700MB disc between 2 and 5 minutes. |
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| Q: |
Is it possible to write to CD-Rs more than once? |
| A: |
Yes and no! If the disc has been left OPEN it can be written to again, although no existing data on the disc can be overwritten. This is known as multi-session recording. Data is written to the disc in sessions and if the session is left OPEN then another session
may be added later (up to 99 sessions can be written to a single disc!). Generally, when writing to CD-Rs they are CLOSED by default, meaning that no further writing can be done. When we create a master or duplicate a CD-R we automatically CLOSE the disc, so no
more data can be added. If you need your discs to be left OPEN allowing further data to be appended, we can do this, but let us know first! |
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| Q: |
Why should my master NOT be 'Packet-Written'? |
| A: |
Packet-writing is a technology that allows you to write very small chunks of data to the CD. This gives you the ability to write single files to a CD, for example when dragging and dropping files in Windows Explorer, rather than having to write a whole track
or disc in one go. There are a few problems concerning packet-written discs:
a) a number of older CD-ROM drives cannot handle these discs
b) some O/S need extra software installed, not good when distributing CDs
c) CD duplicating systems have trouble making accurate copies of packet-written CDs and the data will have to be re-mastered
...so please, DON'T use a packet-written CD-R as your master!! |
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| Q: |
How should I create my master CD? |
| A: |
When supplying master CDs, ALWAYS
use conventional CD writing software,
such as Nero or Toast. Assemble
the files destined for the CD into a
folder on your hard disk. Arrange
the files into the same file & folder
layout that you wish to see on the CD,
and then burn the files using the Disc-At-Once
(DOA) mode of your CD writing software.
This way your master will contain all
the necessary files, and the disc will
be finalised (closed) correctly.
MOST IMPORTANT! We know it sounds daft and we don't mean to teach your Grandmother to suck eggs, but here goes.......don't forget to test your master thoroughly before sending it to us, checking it on a number of different machines and operating systems
to ensure it works correctly. A common mistake is for authors to link files together ABSOLUTELY rather than RELATIVELY, so if you've been developing a project on your local hard disk, then make sure the links in your software are like this...
..\presentations\sample.mpg
... and NOT like this:
C:\company\clients\project1\presentations\sample.mpg |
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| Q: |
How can I get my CD master to you? |
| A: |
Preferably as a master CD-R, well protected & wrapped, and delivered in the post or by courier/carrier! It may sound strange in these days of high-speed electronic transfer, but it's better for us to receive a CD to copy that you have already tested. Of
course if time is tight, the data files can always be uploaded to our FTP site where we can create the master for you. Contact us for address, username and password details to access our FTP server. |
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| Q: |
Can you make my CDs 'autorun'? |
| A: |
For a Windows PC, yes we can - and we also have an article on the website explaining how to create an autorun CD.
For the Mac No! Unfortunately Apple have decided to discontinue support for the autorun function in Mac OS X as they felt it posed a security risk. |
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| Q: |
Are you able to copy HFS CDs for the Apple Mac? |
| A: |
Yes, we can copy just about all CDs as the systems we use do not 'see' the particular formats, just a series of digital 1's and 0's. |
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| Q: |
What is a hybrid CD? |
| A: |
It's the term given to a CD-ROM which
contains two file structures - usually
ISO 9660 (PC) and HFS (Mac), enabling
the CD to be used on both Mac and PC
platforms. Often, hybrid CDs have 'three
areas', Mac only, PC only, and an area
containing common data, accessible by
both file systems - possibly movies,
audio or high resolution images - saving
the need to write large space-hungry
files to the CD twice. If required,
we are able to create hybrid CDs for
you - in fact we do this regularly for
clients when authoring
press release CDs. |
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| Q: |
At what point do I get my CDs pressed rather than duplicated? |
| A: |
Usually when you require upwards of 1000 discs - although this is only a guideline. There have been situations where we have duplicated over 7000 CD-Rs due to time constraints! See Duplication -v- Replication
for a more comprehensive answer. |
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| Q: |
I need a large number of discs but must have them in a few days. |
| A: |
Through experience we often find the rush is due to a trade show (or some equivalent) with about 10% of the discs needed urgently, and the remaining discs needed within a week or two. The best solution is to duplicate the number of discs you absolutely MUST
have and then replicate the rest to arrive later. On the odd occasion where ALL the discs have been required urgently, we have been known to work the odd miracle! So if you find yourself in a tight spot, give us a call. |
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