Wednesday, September 30, 2009

Tips for Burning CD / DVDs

The ability to burn up to 650 Mb of data onto a CD is wonderful thing. However, the burn process can be problem-prone. But there are also many things you can do to avoid some of the most common problems. Below are suggestions for helping you create a perfect disc every time.

1. Use high quality disc. Defects in the media will cause defects in your written disc. Sometimes you can see physical defects in the media on the underside (where you are writing through the disc to the recording layer under the printed side, or in the middle of a DVD±R/RW). Physical defects include things like scratches, scuffs, stains, contamination, defects in the plastic, pinholes in the metal layer, or areas where the recording dye is missing.
2. Keep your hands off the disc... or at least the underside of the disc. Don’t use a "gorilla grip". Grab the disc by stretching your hand across the topside, so you are only touching the outer edges of the disc. Or, place one finger in the center hole and your thumb on the outer edge. Fingerprints or dirt on the bottom of the disc can cause distortion of the writing or reading laser.
3. Keep it dust-free. Store them in cases or sleeves, or keep the spindle of blank discs covered. Before you burn, take a look at the underside surface of the disc. If you see any dust, blow it off with a gentle shot of clean, filtered compressed dry air (not by blowing on it with your mouth). If you don’t have clean compressed air, you can gently wipe off a dusty disc with a clean, dry cloth, but you run the risk of scratching or smearing the surface.
4. Never wipe discs in a circle. In general, we don’t recommend trying to clean discs. In an otherwise hopeless case, you can try some warm soapy water, without scrubbing the surface. Rinse with warm water and dry using a compressed air or a clean cloth.
5. Burn using Disc-at-Once mode. Track-At-Once mode is meant to help avoid buffer underruns on slower computers, but causes overlapping sectors in between tracks called "link transitions". While this is allowed by the DVD specification, these discs are not suitable for use as a Master Disc for DVD Replication facilities, due to the digital errors between tracks, or possible discontinuity of the DVD timecode. In general, use Disc-at-Once unless you have to use Track-at-Once.
6. Don’t leave open sessions. Unless you are storing data in increments to a recordable disc (using multi-session recording), you should "finalize" you’re recording. This will allow your burning software program to write a lead-out to the end of your session. This is necessary for compatibility with audio CD players.
7. Close other programs. If you have problems with buffer underruns, you should choose a slower writing speed. You should also turn off virus protection software. For the best results, don’t run any other programs while you are burning.
8. Keep your hard disks defragmented. While this is a good idea for better PC performance in general, it is an especially good idea for people who do a lot of audio or video editing, or other multimedia production. If your hard disk is highly fragmented, it will have to seek too many sections in order to read and write each file. This will slow down the transfer rate of data to and from the hard drive, and it could cause buffer underruns when burning. In general, don’t let your hard drive fill up more than 75% to 80%. The hard drive fills up from outside to inside - the opposite of CDs and DVDs. This is because the transfer rate is faster at the outside, due to the greater circumference. So, the portion of the hard drive that is written to when your drive is nearly full is slower than the portion that is written to when it is nearly empty. Also, a defragmenter won’t run well or won’t run at all when the drive is too full, as it needs space to work. (see How to use Disk Defragmenter)
9. Slow your burning speed down. While higher speed recording saves time and generally results in great discs, slower speed recordings may give you your best chance for a higher quality disc, with lower error rates. If you think you have problems, or if you have time to burn, slow your burning speed down.
10. Do not burn CD from a network drive: (for example an E: drive, which is linked to a server somewhere on campus). Our network is relatively slow, and data will not be transferred fast enough to keep the burning buffer full. To reiterate: If the burning buffer empties, your burn will fail completely. Always burn using data situated on your LOCAL hard drive.