When 35 mm. film has been copied onto another format, whether the copying is onto film (e.g., a 16 mm. reduction) or onto video, the relationship of the original unit count to the new unit count can become complicated to express in the line of physical description.  State the number of units in hand and the number of units in the complete copy, if  known, in terms of the film or video format being described, rather than in terms of the original 35 mm. format.  If the unit count of the original is known, it should be given in a note.

300 ## $a 3 film reels of 3 (ca. 80 min., 2,875 ft.) : $b sd., col. ; $c 16 mm. $3 viewing print.

500 ## $a Originally on ten 1,000-ft. 35 mm. reels.

300 ## $a 2 videodiscs of 2 (CED) (85 min.) : $b sd., col. ; $c 12 in. $3 viewing copy.

--not--

300 ## $a 10 film reels of 10 on 2 videodiscs of 2 (CED) (85 min.) : $b sd., col. ; $c 12 in. $3 viewing copy.

See also:

5B3.  Number of units in a complete work

5B.  Extent of work and specific material designation

5.  Physical Description Area