SCHEDULE 14A INFORMATION

           Proxy Statement Pursuant to Section 14(a) of the Securities
                      Exchange Act of 1934 (Amendment No. )

Check the appropriate box:                 
[ ]  Preliminary Proxy Statement           [ ]  Confidential, for Use of the   
[ ]  Definitive Proxy Statement                 Commission Only (as permitted by
[X]  Definitive Additional Materials            Rule 14a-6(e)(2))               
[ ]  Soliciting Material Pursuant to       
     Rule 14a-11(c) or Rule 14a-12       


                             PINNACLE SYSTEMS, INC.
- --------------------------------------------------------------------------------
                (Name of Registrant as Specified in its Charter)

                             PINNACLE SYSTEMS, INC.
- --------------------------------------------------------------------------------
                   (Name of Person(s) Filing Proxy Statement)


Payment of Filing Fee (Check the appropriate box):
[X] No fee required.
[ ] Fee computed on table below per Exchange Act Rules 14a-6(i)(1) and 0-11.

         (1)      Title  of  each  class  of  securities  to  which  transaction
                  applies:

- --------------------------------------------------------------------------------

         (2)      Aggregate number of securities to which transaction applies:

- --------------------------------------------------------------------------------

         (3)      Per  unit  price  or other  underlying  value  of  transaction
                  computed pursuant to Exchange Act Rule 0-11:

- --------------------------------------------------------------------------------

         (4)      Proposed maximum aggregate value of transaction

- --------------------------------------------------------------------------------

         (5)      Total fee paid:

- --------------------------------------------------------------------------------

[ ]      Fee paid previously with preliminary materials.

- --------------------------------------------------------------------------------

[ ]      Check box if any part of the fee is offset as provided by Exchange  Act
         Rule  0-11(a)(2)  and identify the filing for which the  offsetting fee
         was paid  previously.  Identify  the  previous  filing by  registration
         statement number, or the Form or Schedule and the date of its filing.

             (1)   Amount Previously Paid:

             -------------------------------------------------------------------

             (2)   Form, Schedule or Registration Statement No.:

             -------------------------------------------------------------------

             (3)   Filing Party:

             -------------------------------------------------------------------

             (4)   Date Filed:

             -------------------------------------------------------------------





                             PINNACLE SYSTEMS, INC.
                            280 NORTH BERNARDO AVENUE
                             MOUNTAIN VIEW, CA 94043

                                   May 6, 1999


A Message to Our Shareholders,

If you were a holder of Pinnacle  Systems,  Inc. common stock as of the close of
business on March 31, 1999, you should have received a Notice of Special Meeting
and a Proxy Statement relating to the approval of (1) an amendment to Pinnacle's
Articles of Incorporation  to increase the authorized  shares of Common Stock to
30,000,000  (the  "Amendment")  and (2) an  amendment  to  Pinnacle's  Bylaws to
increase the number of directors to a maximum of nine.

Subsequent  to the mailing of the Proxy  Statement,  the Board of  Directors  of
Pinnacle approved a 2-for-1 stock split.  Shareholders of record on May 14, 1999
will be  entitled  to one  additional  share of common  stock for each  share of
Pinnacle  common stock held on that date. The payment date will be June 4, 1999.
Under  California  law, this stock split does not require  shareholder  approval
since  it   increases   the  number  of  shares   outstanding   and   authorized
proportionately.

If the shareholders approve the Amendment at the Special Meeting, the authorized
number of shares will increase from 15,000,000 to 30,000,000 shares.  Then, as a
result  of the  stock  split,  the  Board  of  Directors,  as  authorized  under
California  law,  will be entitled to increase the  authorized  number of shares
proportionately.  As a result  of the  stock  split,  the  number  of  shares of
Pinnacle common stock  outstanding will increase from  approximately  11,152,000
shares to approximately 22,304,000 shares. In addition, as a result of the stock
split,  the number of shares  reserved for issuance  under  Pinnacle's  employee
stock plans and for issuance upon exercise of  outstanding  warrants and options
will double to approximately 6,814,000.

As a result, if the Amendment is not approved by the shareholders, Pinnacle will
have a very  small  amount of  authorized  shares --  approximately  880,000  --
available in the future.  As described  in the Proxy  Statement,  there are many
important corporation  activities that may require additional authorized shares,
such as raising  equity  capital,  adopting  additional  employee stock plans or
reserving  additional  shares for  issuance  under its existing  employee  stock
plans, and making acquisitions  through the use of stock. The Board of Directors
believes  that,  notwithstanding  the stock split,  approval of the Amendment is
very  important  to ensure that the  Company  will have a  sufficient  number of
shares  available  should it decide to use its  shares  for one or more of these
activities in the future.

Therefore,  we urge you to approve  the  Amendment  to increase  the  authorized
number of shares of common stock.  If you have not yet voted your shares for the
Amendment,  we encourage  you to do so on the proxy card that was enclosed  with
the  Proxy  Statement.  Proxy  cards  that are not  returned  are  automatically
recorded as a vote against the proposals being presented at the Special Meeting.
Therefore,  if you support the amendment,  you need to vote "YES" and return the
form at your earliest convenience. If your stock is held in a brokerage account,
you should  telephone  your broker and  request  that the proxy  information  be
forwarded to you immediately.

If you have already mailed in a proxy card, you may revoke it at any time before
its use at the Special  Meeting by  delivering  to the  Secretary  of Pinnacle a
written notice of revocation or a duly executed proxy bearing a later date or by
attending the special meeting and voting in person.


                                  Arthur D. Chadwick,
                                  Vice President, Finance and Administration,
                                  Chief Financial Officer and Secretary