Editing Capacitance Electronic Disc (section)

== Disadvantages ==

In comparison with [[LaserDisc]] technology, CEDs suffered from the fact that they were a phonograph-style contact medium: RCA estimated that the number of times a CED videodisc could be played back, under ideal conditions, was 500.<ref name = "last">{{cite web | title = RCA SelectaVision VideoDisc FAQ - How long can I expect my CED VideoDiscs to last? | publisher = CEDMagic.com | url = http://cedmagic.com/home/cedfaq.html#threetwelve | access-date = 2007-03-14}}</ref> By comparison, a clean, [[laser rot]]-free LaserDisc could, in theory, be played an unlimited number of times (although repeated or careless  handling could still result in damage). 

Since the CED system used a stylus to read the discs, it was necessary to regularly change the stylus in the player to avoid damage to the videodiscs, while worn and damaged discs also caused problems for consumers. When a disc began to wear, video and audio quality would severely decline, and the disc would begin to skip.<ref name = "last" />  Several discs suffered from a condition called "video virus", where a CED would skip a great deal due to dust particles stuck in the grooves of the disc. However, playing the disc several times would generally solve this problem.<ref>{{cite web | title = RCA SelectaVision VideoDisc FAQ - Why do some of my CED's skip, and what can I do to correct this? | publisher = CEDMagic.com | url = http://cedmagic.com/home/cedfaq.html#threenine | access-date = 2007-03-14}}</ref>

Unlike [[VHS]] tapes, CEDs (along with LaserDisc) required a disc flip (however, some LaserDisc players were able to read both sides of the disc without physically flipping the disc, achieved by moving the laser from one side of the disc to the other, but this still resulted in a pause of playback during the change) at some point during the course of almost all films as only sixty minutes of video could be stored per side (75 mins on UK PAL discs due to the slower rotation speed); if a feature ran over two hours, it would be necessary to spread the feature over two discs. 

In some cases, if a movie's theatrical running time was only slightly longer than two hours, studios would often trim short scenes throughout the movie and/or employ time compression (speeding the extra run time out of the film) in order to avoid the expense of issuing two discs.

This problem was not unique to CEDs: LaserDiscs presented the same difficulty, and some longer features, such as ''[[The Ten Commandments (1956 film)|The Ten Commandments]]'' (1956), still required more than one tape or disc in the VHS, Beta, and [[LaserDisc]] formats. There were no two-disc UK PAL releases.

Less significant disadvantages include lack of support for [[Freeze frame shot|freeze-frame]] during pause, since CEDs scanned four frames in one rotation versus one frame per rotation on CAV LaserDisc, while computer technology was not advanced enough at the time to outfit the player with a [[framebuffer]] affordably. However, a "page mode" was available on many players that would allow those four frames to be repeated in an endless loop.<ref>{{cite web | title = CED Player Specifications | publisher = CEDMagic.com | url = http://www.cedmagic.com/museum/ced-player-guide/ced-player-specifications.html | access-date = 2008-03-14}}</ref>

CEDs were also larger than VHS tapes, thicker than LaserDiscs, and considerably heavier due to the plastic caddies.