(a) Depositions and other discovery material otherwise required to be filed with the court under this chapter shall not be required to be so filed unless:

(1) Required by local rule of court;

(2) Ordered by the court;

(3) Requested by any party to the action;

(4) Relief relating to discovery material is sought under this chapter and said material has not previously been filed under some other provision of this chapter, in which event copies of the material in dispute shall be filed by the movant contemporaneously with the motion for relief; or

(5) Such material is to be used at trial or is necessary to a pretrial or posttrial motion and said material has not previously been filed under some other provision of this chapter, in which event the portions to be used shall be filed with the clerk of the court at the outset of the trial or at the filing of the motion, insofar as their use can be reasonably anticipated by the parties having custody thereof, but a party attempting to file and use such material which was not filed with the clerk at the outset of the trial or at the filing of the motion shall show to the satisfaction of the court, before the court may authorize such filing and use, that sufficient reasons exist to justify that late filing and use and that the late filing and use will not constitute surprise or manifest injustice to any other party in the proceedings.

(b) Until such time as discovery material is filed under paragraphs (1) through (5) of subsection (a) of this Code section, the original of all depositions shall be retained by the party taking the deposition and the original of all other discovery material shall be retained by the party requesting such material, and the person thus retaining the deposition or other discovery material shall be the custodian thereof.