A cam is a theater rip usually done with a digital video camera. A mini tripod is sometimes used, but a lot of the time this wont be possible, so the camera make shake. Also seating placement isn't always idle, and it might be filmed from an angle. If cropped properly, this is hard to tell unless there's text on the screen, but a lot of times these are left with triangular borders on the top and bottom of the screen. Sound is taken from the onboard microphone of the camera, and especially in comedies, laughter can often be heard during the film. Due to these factors picture and sound quality are usually quite poor, but sometimes we're lucky, and the theater will be fairly empty and a fairly clear signal will be heard.
A telesync is the same spec as a CAM except it uses an external audio source (most likely an audio jack in the chair for hard of hearing people). A direct audio source does not ensure a good quality audio source, as a lot of background noise can interfere. A lot of the times a telesync is filmed in an empty cinema or from the projection booth with a professional camera, giving a better picture quality. Quality ranges drastically, check the sample before downloading the full release. A high percentage of Telesyncs are CAMs that have been mislabeled.
A telecine machine copies the film digitally from the reels. Sound and picture should be very good, but due to the equipment involved and cost telecines are fairly uncommon. Generally the film will be in correct aspect ratio, although 4:3 telecines have existed. A great example is the JURASSIC PARK 3 TC done last year. TC should not be confused with TimeCode , which is a visible counter on screen throughout the film.
A pre VHS tape, sent to rental stores, and various other places for promotional use. A screener is supplied on a VHS tape, and is usually in a 4:3 (full screen) a/r, although letterboxed screeners are sometimes found. The main draw back is a "ticker" (a message that scrolls past at the bottom of the screen, with the copyright and anti-copy telephone number). Also, if the tape contains any serial numbers, or any other markings that could lead to the source of the tape, these will have to be blocked, usually with a black mark over the section. This is sometimes only for a few seconds, but unfortunately on some copies this will last for the entire film, and some can be quite big. Depending on the equipment used, screener quality can range from excellent if done from a MASTER copy, to very poor if done on an old VHS recorder thru poor capture equipment on a copied tape. Most screeners are transferred to VCD, but a few attempts at SVCD have occurred, some looking better than others.
Same premise as a screener, but transferred off a DVD. Usually letterbox , but without the extras that a DVD retail would contain. The ticker is not usually in the black bars, and will disrupt the viewing. If the ripper has any skill, a DVDscr should be very good. Usually transferred to SVCD or DivX/XviD.
R5 RETAIL (R5)
Over the past 6 months the major movie studios have been releasing retail dvds early in Russia. They do this to stop the widespread use of pirated telecines (which were once very common). Lately however there has been very few real telecines, most of the scene telecines you see are actually R5 retails.
R5 retail is rushed out by the studio, they are basically competing with pirates, so there is little to no cleanup of the film after the telecine process. So the main difference between telecines put out by the pirates is that the r5's are done using pro equipment, professional studios and professional people. The quality of R5 retail is very similar to dvdscr's, no time is usually spent cleaning up dvdscrs either.
A copy of the final released DVD. If possible this is released PRE retail (for example, Star Wars episode 2) again, should be excellent quality. DVDrips are released in SVCD and DivX/XviD.
The range of quality we now have is like this.
R1/2 retail > DVDRIP > R5 Retail > DVDSCR > Telecine > Telesync > Cam.