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                                                                 EXHIBIT 10.16


                                   AMENDMENT


         This Amendment Agreement dated as of the 2nd day of August, 1999, by
and between Box Hill Systems Corp., a New York corporation (the "Company"), and
Philip Black, residing at 15 Cornel Drive, Goldens Bridge, New York 10526
("Executive").

         WHEREAS, the parties hereto entered into a compensation plan and
agreement dated January 1, 1999 (the "Employment Agreement"), whereby the
Company agreed to retain Executive's services, and Executive agreed to serve, as
Chief Executive Officer of the Company;

         WHEREAS, as of August __, 1999, the Company consummated the
transactions contemplated by the Agreement and Plan of Merger dated April 29,
1999, by and among the Company, BH Acquisition Corp., a Delaware corporation,
and Artecon, Inc., a Delaware corporation (the "Merger"); and

         WHEREAS, the Company and Executive have agreed to amend the Employment
Agreement in connection with the Merger.

         NOW THEREFORE, in consideration of the mutual promises and agreements
set forth herein, the receipt and sufficiency of which the parties hereby
acknowledge, the parties hereby agree as follows:

1.            TITLES. From and after the date hereof, Executive's titles
shall be (i) Co-Chief Executive Officer, and/or (ii) Executive Vice
President, International Sales and Operations.

2.            LOCATION. Executive shall relocate his residence to Santa
Barbara, California, and will perform his duties at any of the Company's
offices (both domestic and internationally) or from his home as he feels
appropriate.

3.            COMPENSATION. (a) Executive's base salary, on an annualized
basis, for the remainder of Calendar Year 1999 shall be $300,000.

                            (b) The provisions for bonus payments and
commissions earned for the remainder of Calendar Year 1999 and Calendar Year
2000, if any, contained in Attachment A to the Employment Agreement are
hereby replaced by the terms contained on Schedule 1 attached hereto.

4.       NO OTHER AMENDMENTS. All terms of the Employment Agreement, including
Attachment A, shall continue in full force and effect as of the date hereof,
except as specifically stated herein.

                                1.
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         IN WITNESS WHEREOF, the parties hereto have executed this Amendment
Agreement as of the date first set forth above.

BOX HILL SYSTEMS CORP                         PHILIP BLACK

By:  /s/ Benjamin Monderer                    By:  /s/ Philip Black
   ---------------------------------             ------------------------------
   Name: Benjamin Monderer                       Name: Philip Black
   Title: President                              Title: CEO

                                  2.

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                                   SCHEDULE 1

QUARTERLY PERFORMANCE BONUS

Each quarter, you shall be eligible for a performance bonus of up to 50% of your
base salary for such quarter (Quarterly Bonus). The Quarterly Bonus shall be
based on the following formula, and on the Company's Business Plan, as approved
by the Board of Directors, for such quarter:

FORMULA

1.       REVENUE-BASED BONUS: Half of the Quarterly Bonus shall be based on
revenue. If the Company meets the Business Plan revenue goals for any given
quarter, you shall be entitled to half of the Quarterly Bonus (25% of your base
salary for such quarter) for performance during the quarter. If the Company
fails to meet the Business Plan revenue goals for a given quarter, then the
revenue-based bonus shall be paid as follows:

         if the Company attains less than 75% of the Business Plan revenue
         goals, you shall not receive any revenue-based bonus for that quarter.
         For attaining levels of revenue between 75% and 100% of plan, you shall
         receive 2% of the total Quarterly Bonus for every 1% of revenue above
         75%.

2.       INCOME-BASED BONUS: Half of the Quarterly Bonus is to be based on net
income. If the Company meets the Business Plan net income goals for any given
quarter, then you shall be entitled to half of the Quarterly Bonus (25% of your
salary for such quarter) for performance during that quarter. If the Company
fails to meet the Business Plan net income goals for a given quarter, then the
net income-based bonus shall be paid as follows:

         0.5% of the Quarterly Bonus, payable for each 1% achieved of the net
         income line of the Business Plan, up to a maximum of 100%.

BUSINESS PLAN DETERMINATIONS

Third Quarter, 1999: You shall be granted full bonus (50% of base salary).

Fourth Quarter, 1999: You shall be granted a bonus pursuant to the formula set
forth above, based on the Business Plan for the Fourth Quarter, to be approved
by the Board during the Fourth Quarter.

Fiscal Year 2000: You shall be granted bonus pursuant to the formula set forth
above, based on the Business Plan for the Year 2000, to be approved by Board
during the First Quarter of 2000.

                                  3.