Exhibit 4.1

                           ACCENT COLOR SCIENCES, INC.
                            800 Connecticut Boulevard
                        East Hartford, Connecticut 06108

October 28, 1999



Zanett Lombardier, Ltd.
c/o Olympia Capital (Cayman) Limited
Williams House
20 Reid Street
Hamilton HM 11
Bermuda

RGC International Investors
Rose Glen Capital Management, L.P.
c/o Rose Glen Capital Group
3 Bala Plaza - East Suite 200
Bala Cynwyd, PA

Dear Ladies and Gentlemen:

         This letter is intended to modify the letter of agreement  between each
of you and Accent Color Sciences, Inc. (the "Company"),  dated September 3, 1999
concerning your shares of Series B Convertible Preferred Stock of the Company in
connection with our current financing effort (the "September 3 Letter"). Each of
you has  previously  executed a term sheet  containing an agreement in principal
under  which the  Company  may either  redeem  your shares of Series B Preferred
Stock (the  "Series B Stock")  for their face  amount  plus  accrued  premium or
convert your shares of Series B Stock into common stock at the prevailing  price
in a previously proposed common stock placement, as described in the September 3
Letter.  In response to the  interest of  potential  investors,  the Company has
accepted the  recommendation  of its investment  banker,  Pennsylvania  Merchant
Group, to offer investors  shares of a new series of preferred stock  designated
the Series C Convertible  Preferred  Stock (the "Series C Stock").  The Series C
Stock would have a  liquidation  preference  of $100.00 per share,  no preferred
dividend  (however no dividends may be paid on the common stock without at least
an equivalent  dividend paid on the Series C Stock ), no redemption rights (with
respect to either the  holders  of Series C Stock or the  Company)  and would be
convertible  initially  at the rate of 250 shares of Common stock for each share
of Series C Stock (a conversion rate of $.40 per share),  subject to such change
in the  initial  conversion  rate  as  may be  necessitated  to  reflect  market
conditions  and to ongoing  anti-dilution  rights in the event of stock  splits,
recapitializations  and the  like.  The  holders  of Series C Stock  would  have
identical  voting  rights to the voting  rights which you have as holders of the
Company's  Series B Stock. The rights and preferences of the Series C Stock will
be  substantially  as set forth in the draft  designation  of the Series C Stock
attached to this letter agreement as Exhibit A.

<PAGE>

         For reasons  substantially  similar to those set out in the September 3
Letter,  we  continue  to need your  cooperation  in order to pursue the current
financing  which will  require  the same number of  authorized  shares of common
stock to  support  the  conversion  rights of holders of Series C Stock as would
have been required for the common stock private  placement.  However,  we can no
longer  expect you to convert  your shares of Series B Stock into common  stock,
assuming the conditions  referred to in the September 3 Letter are met. Instead,
we have  discussed  with you and  understand  that you will agree to modify,  in
accordance with the provisions of this letter agreement,  your rights as holders
of all  outstanding  shares  of the  Series B Stock so as to be  similar  to the
rights of the holders of Series C Stock, subject however to the prior conditions
recited below.

         The agreements set forth below are subject to the prior satisfaction or
fulfillment of each of the following conditions:

         (a) The  Company  shall  raise  gross  proceeds  of at least $4 million
including both the proceeds of the bridge financing referred to in the September
3 Letter and the proposed sale of shares of Series C Stock;

         (b) The  Company  will  call and hold on or before  December  2, 1999 a
shareholders'  meeting and obtain the  approval  of an  increase  in  authorized
shares of the  Company's  common  stock such that the  authorized  shares of the
Company's  common stock shall be fully  sufficient  to support  your  conversion
rights as holders of Series B Stock; and

         (c) In the event that  Company  shall fail to obtain  such  shareholder
approval in accordance with the preceding  subparagraph (b), (or otherwise fully
restore  your  conversion  rights such as through a reverse  stock  split),  the
Company  will be  required  to redeem the Series B Stock for cash in  accordance
with the provisions of the bridge financing term sheet.

         Assuming fulfillment of each of the preceding  conditions,  each of you
agrees with us as follows:

         1. We will hold a  meeting  of  shareholders  to  authorize  additional
shares of common  stock as soon as possible  and no later than  December 2, 1999
(it being the  Company's  current  intention to hold the meeting on November 29,
1999);

         2. That in the  interim  prior to such  meeting,  you will  retain your
rights as holders of Series B Stock,  subject to the  provisions  of this letter
and the bridge financing term sheet;

         3. Your annual  premium on your shares of Series B Stock will  continue
to accrue until your shares of Series B Stock are actually  redeemed,  converted
or modified as provided in subparagraph 4 below;


<PAGE>


         4. That upon  receipt of such  shareholder  approval and the closing of
the  private  placement  of Series C Stock,  and  assuming  the  Company has not
elected to redeem your shares of Series B Stock for cash as specified above, the
terms, rights and preferences of your shares of Series B Stock shall be modified
as follows:

                   (i) The annual  premium on the Series B Stock  shall cease to
accrue;

                  (ii) The liquidation  preference  amount of the Series B Stock
shall immediately  become and thereafter remain an amount per share equal to the
face amount  thereof  ($1,000) plus the then accrued annual premium (6% per year
from date of issuance);

                  (iii) The  conversion  price shall,  for all purposes,  be the
conversion price applicable to the Series C Stock, from time to time, determined
by dividing  the number of shares of common stock into which one share of Series
C stock is then convertible into $100;

                  (iv) The Company  shall  continue  and  maintain an  effective
registration  statement with the Securities and Exchange Commission with respect
to the common shares  issuable on conversion of the Series B stock in accordance
with the Registration Rights Agreement among us dated January 9, 1998;

                  (v) All rights and  obligations  of either the  Company or the
holders of Series B Stock regarding  voluntary or involuntary  redemption by the
Company of shares of Series B Stock shall be terminated, except that the holders
of Series B Stock shall be entitled to any such  redemption  rights as may apply
with respect to the Series C Stock;

                  (vi) All  limitations  on conduct and  approval  rights of the
Company set forth in Article XIII of the designation of the Series B Stock shall
no longer  apply  except to the extent  that any such  limitations  or  approval
rights are applicable with respect to the Series C Stock;

                  (vii) All remedies set forth in the  designation of the Series
B Stock  shall no longer  apply  except to the  extent  that such  remedies  are
similar to remedies available to holders of Series C Stock;

                  (viii) The  limitation  on the amount of Series B Stock  which
may be  converted  into common  stock at any one time set forth in  subparagraph
(ii) of Paragraph C of Article IV of the designation of the Series B Stock shall
continue to apply;

                  (ix) The  Company  shall at all  times  reserve  a  sufficient
number of shares of its common stock as may be issuable  upon the  conversion of
all then outstanding shares of Series B Stock;

<PAGE>


                  (x) The  holders  of Series B Stock  shall  rank,  in right of
payment,  pari  passu with the  holders  of Series C Stock with  respect to both
dividends and payments upon liquidation; and

                  (xi) No  transfer of shares of Series B Stock by either of you
shall be permitted  unless, in addition to complying with any other statutory or
contractual  restrictions upon such transfer,  the transferee shall agree to the
provisions of this letter agreement.

         We again express our  appreciation for your cooperation in facilitating
our  financing  effort.  Please  indicate  your consent and  agreement  with the
foregoing provisions by dating, signing and returning to me the enclosed copy of
this letter.

                                          Sincerely,


                                          ---------------------------------
                                          Charles E. Buchheit
                                          President and Chief Executive Officer


Consented and Agreed to:


ZANETT LOMBARDIER, LTD.



By:______________________________________   Date: _________________________


RGC INTERNATIONAL INVESTORS, LDC
BY:  ROSE GLEN CAPITAL MANAGEMENT, L.P.
BY:  RGC GENERAL PARTNER CORP.


By:______________________________________   Date: _________________________