SUPPLEMENTAL INDENTURE


     Supplemental Indenture (this "Supplemental Indenture"), dated as of
April 1, 2004 among IMAX Corporation, a corporation incorporated under the
federal laws of Canada (the "Company"), the Guarantors named in the Indenture
referred to below (the "Existing Guarantors"), Taurus-Littrow Productions Inc.
and 3D Sea II Ltd. (each, a "Guaranteeing Subsidiary") and U.S. Bank National
Association, as trustee under the Indenture referred to below (the "Trustee").


                               W I T N E S S E T H

     WHEREAS, the Company and the Existing Guarantors have heretofore executed
and delivered to the Trustee an indenture (the "Indenture"), dated as of
December 4, 2003, providing for the issuance of 9 5/8% Senior Notes due 2010
(the "Securities");

     WHEREAS, the Indenture provides that under certain circumstances each
Guaranteeing Subsidiary shall execute and deliver to the Trustee a supplemental
indenture pursuant to which any newly-acquired or created Guarantor shall
unconditionally guarantee all of the Company's obligations under the Securities
and the Indenture on the terms and conditions set forth herein (the "Subsidiary
Guarantee"); and

     WHEREAS, pursuant to Section 901 of the Indenture, the Trustee is
authorized to execute and deliver this Supplemental Indenture.

     NOW THEREFORE, in consideration of the foregoing and for other good and
valuable consideration, the receipt of which is hereby acknowledged, each
Guaranteeing Subsidiary and the Trustee mutually covenant and agree for the
equal and ratable benefit of the Holders of the Securities as follows:

     1.  Capitalized Terms. Capitalized terms used herein without definition
shall have the meanings assigned to them in the Indenture.

     2.  Agreement to Guarantee. Each Guaranteeing Subsidiary irrevocably and
unconditionally guarantees the Guarantee Obligations, which include (i) the due
and punctual payment of the principal of, premium, if any, and interest and
Special Interest, if any, on the Securities, whether at maturity, by
acceleration, redemption, upon a Change of Control Offer, upon an Asset Sale
Offer or otherwise, the due and punctual payment of interest on the overdue
principal and premium, if any, and (to the extent permitted by law) interest on
any interest on the Securities, and payment of expenses, and the due and
punctual performance of all other obligations of the Company, to the Holders or
the Trustee all in accordance with the terms set forth in Article XIII of the
Indenture, and (ii) in case of any extension of time of payment or renewal of
any Securities or any such other obligations, that the same will be promptly
paid in full when due or performed in accordance with the terms of the extension
or renewal, whether at stated maturity, by acceleration, redemption, upon a
Change of Control Offer, upon an Asset Sale Offer or otherwise.

     The obligations of each Guaranteeing Subsidiary to the Holders and to the
Trustee pursuant to this Subsidiary Guarantee and the Indenture are expressly
set forth in Article XIII of the Indenture and reference is hereby made to such
Indenture for the precise terms of this Subsidiary Guarantee.

     No past, present or future director, officer, partner, manager, employee,
incorporator or stockholder (direct or indirect) of either of the Guaranteeing
Subsidiaries (or any such successor entity), as such, shall have any liability
for any obligations of such Guaranteeing Subsidiary under this Subsidiary
Guarantee or the Indenture or for any claim based on, in respect of, or by
reason of, such obligations or their creation, except in their capacity as an
obligor or Guarantor of the Securities in accordance with the Indenture.

     This is a continuing Guarantee and shall remain in full force and effect
and shall be binding upon each Guaranteeing Subsidiary and its successors and
assigns until full and final payment of all of the Company's obligations under
the Securities and Indenture or until released in accordance with the Indenture
and shall inure to the benefit of the successors and assigns of the Trustee and
the Holders, and, in the event of any transfer or assignment of rights by any
Holder or the Trustee, the rights and privileges herein conferred upon that
party shall automatically extend to and be vested in such transferee or
assignee, all subject to the terms and conditions hereof. This is a Guarantee of
payment and not of collectibility.






     The obligations of each Guaranteeing Subsidiary under its Subsidiary
Guarantee shall be limited to the extent necessary to insure that it does not
constitute a fraudulent conveyance under applicable law.

     THE TERMS OF ARTICLE XIII OF THE INDENTURE ARE INCORPORATED HEREIN BY
REFERENCE.

     3.  NEW YORK LAW TO GOVERN. THE LAWS OF THE STATE OF NEW YORK SHALL GOVERN
AND BE USED TO CONSTRUE THIS SUPPLEMENTAL INDENTURE.

     4.  Counterparts. The parties may sign any number of copies of this
Supplemental Indenture. Each signed copy shall be an original, but all of them
together represent the same agreement.

     5.  Effect of Headings. The Section headings herein are for convenience
only and shall not affect the construction hereof.







     IN WITNESS WHEREOF, the parties hereto have caused this Supplemental
Indenture to be duly executed and attested, all as of the date first above
written.

                               IMAX Corporation


                               By /s/ G. Mary Ruby
                                 -----------------------------------
                               Name:  G. Mary Ruby
                               Title: Sr. Vice President, Legal Affairs


                               By /s/ Edward MacNeil
                                 -----------------------------------
                               Name:  Edward MacNeil
                               Title: Vice President Finance, Special Projects


                               EXISTING GUARANTORS:

                               David Keighley Productions 70MM Inc.


                               By /s/ G. Mary Ruby
                                 -----------------------------------
                               Name:  G. Mary Ruby
                               Title: Secretary


                               By /s/ Edward MacNeil
                                 -----------------------------------
                               Name:  Edward MacNeil
                               Title: Vice President



                               IMAX II U.S.A. Inc.


                               By /s/ G. Mary Ruby
                                 -----------------------------------
                               Name:  G. Mary Ruby
                               Title: Secretary


                               By /s/ Edward MacNeil
                                 -----------------------------------
                               Name:  Edward MacNeil
                               Title: Vice President



                                       3


                               IMAX Chicago Theatre LLC
                               By its Managing Member
                               IMAX Theatre Holding (California I) Co.


                               By /s/ G. Mary Ruby
                                 -----------------------------------
                               Name:  G. Mary Ruby
                               Title: Secretary


                               By /s/ Edward MacNeil
                                 -----------------------------------
                               Name:  Edward MacNeil
                               Title: Vice President



                               IMAX Forum Ride, Inc.


                               By /s/ G. Mary Ruby
                                 -----------------------------------
                               Name:  G. Mary Ruby
                               Title: Secretary


                               By /s/ Edward MacNeil
                                 -----------------------------------
                               Name:  Edward MacNeil
                               Title: Vice President



                               IMAX Minnesota Holding Co.


                               By /s/ G. Mary Ruby
                                 -----------------------------------
                               Name:  G. Mary Ruby
                               Title: Secretary


                               By /s/ Edward MacNeil
                                 -----------------------------------
                               Name:  Edward MacNeil
                               Title: Vice President



                               IMAX Rhode Island Limited Partnership
                               By its General Partner
                               IMAX Providence General Partner Co.


                               By /s/ G. Mary Ruby
                                 -----------------------------------
                               Name:  G. Mary Ruby
                               Title: Secretary


                               By /s/ Edward MacNeil
                                 -----------------------------------
                               Name:  Edward MacNeil
                               Title: Vice President


                                       4


                               IMAX Sandde Animation Inc.


                               By /s/ G. Mary Ruby
                                 -----------------------------------
                               Name:  G. Mary Ruby
                               Title: Secretary


                               By /s/ Edward MacNeil
                                 -----------------------------------
                               Name:  Edward MacNeil
                               Title: Vice President



                               IMAX Scribe Inc.


                               By /s/ G. Mary Ruby
                                 -----------------------------------
                               Name:  G. Mary Ruby
                               Title: Secretary


                               By /s/ Edward MacNeil
                                 -----------------------------------
                               Name:  Edward MacNeil
                               Title: Vice President



                               IMAX Space Ltd.


                               By /s/ G. Mary Ruby
                                 -----------------------------------
                               Name:  G. Mary Ruby
                               Title: Secretary


                               By /s/ Edward MacNeil
                                 -----------------------------------
                               Name:  Edward MacNeil
                               Title: Vice President



                               IMAX Theatre Holding Co.


                               By /s/ G. Mary Ruby
                                 -----------------------------------
                               Name:  G. Mary Ruby
                               Title: Secretary


                               By /s/ Edward MacNeil
                                 -----------------------------------
                               Name:  Edward MacNeil
                               Title: Vice President



                                       5


                                IMAX Theatre Holdings (OEI) Inc.


                                By /s/ G. Mary Ruby
                                  -----------------------------------
                                Name:  G. Mary Ruby
                                Title: Secretary


                                By /s/ Edward MacNeil
                                  -----------------------------------
                                Name:  Edward MacNeil
                                Title: Vice President



                                IMAX Theatre Management Company


                                By /s/ G. Mary Ruby
                                  -----------------------------------
                                Name:  G. Mary Ruby
                                Title: Secretary


                                By /s/ Edward MacNeil
                                  -----------------------------------
                                Name:  Edward MacNeil
                                Title: Vice President



                                IMAX Theatre Services Ltd.


                                By /s/ G. Mary Ruby
                                  -----------------------------------
                                Name:  G. Mary Ruby
                                Title: Secretary


                                By /s/ Edward MacNeil
                                  -----------------------------------
                                Name:  Edward MacNeil
                                Title: Vice President



                                IMAX U.S.A. Inc.


                                By /s/ G. Mary Ruby
                                  -----------------------------------
                                Name:  G. Mary Ruby
                                Title: Secretary


                                By /s/ Edward MacNeil
                                  -----------------------------------
                                Name:  Edward MacNeil
                                Title: Vice President



                                       6



                                Miami Theatre LLC
                                By its Managing Member
                                IMAX Theatre Holding (California I) Co.


                                By /s/ G. Mary Ruby
                                  -----------------------------------
                                Name:  G. Mary Ruby
                                Title: Secretary


                                By /s/ Edward MacNeil
                                  -----------------------------------
                                Name:  Edward MacNeil
                                Title: Vice President



                                Mitey Cinema Inc.


                                By /s/ G. Mary Ruby
                                  -----------------------------------
                                Name:  G. Mary Ruby
                                Title: Secretary


                                By /s/ Edward MacNeil
                                  -----------------------------------
                                Name:  Edward MacNeil
                                Title: Vice President


                                Mountainview Theatre Management Ltd.


                                By /s/ G. Mary Ruby
                                  -----------------------------------
                                Name:  G. Mary Ruby
                                Title: Secretary


                                By /s/ Edward MacNeil
                                  -----------------------------------
                                Name:  Edward MacNeil
                                Title: Vice President



                                Nyack Theatre LLC
                                By its Managing Member
                                IMAX Theatre Holding (Nyack I) Co.


                                By /s/ G. Mary Ruby
                                  -----------------------------------
                                Name:  G. Mary Ruby
                                Title: Secretary


                                By /s/ Edward MacNeil
                                   -----------------------------------
                                Name:  Edward MacNeil
                                Title: Vice President



                                       7



                                Ridefilm Corporation


                                By /s/ G. Mary Ruby
                                  -----------------------------------
                                Name:  G. Mary Ruby
                                Title: Secretary


                                By /s/ Edward MacNeil
                                  -----------------------------------
                                Name:  Edward MacNeil
                                Title: Vice President



                                Sacramento Theatre LLC
                                By its Managing Member
                                IMAX Theatre Holding (California I) Co.


                                By /s/ G. Mary Ruby
                                  -----------------------------------
                                Name:  G. Mary Ruby
                                Title: Secretary


                                By /s/ Edward MacNeil
                                  -----------------------------------
                                Name:  Edward MacNeil
                                Title: Vice President



                                Sonics Associates, Inc.


                                By /s/ G. Mary Ruby
                                  -----------------------------------
                                Name:  G. Mary Ruby
                                Title: Secretary


                                By /s/ Edward MacNeil
                                  -----------------------------------
                                Name:  Edward MacNeil
                                Title: Vice President



                                Starboard Theatres Ltd.


                                By /s/ G. Mary Ruby
                                  -----------------------------------
                                Name:  G. Mary Ruby
                                Title: Secretary


                                By /s/ Edward MacNeil
                                  -----------------------------------
                                Name:  Edward MacNeil
                                Title: Vice President



                                       8



                                Tantus Films Ltd.


                                By /s/ G. Mary Ruby
                                  -----------------------------------
                                Name:  G. Mary Ruby
                                Title: Secretary


                                By /s/ Edward MacNeil
                                  -----------------------------------
                                Name:  Edward MacNeil
                                Title: Vice President



                                Wire Frame Films Ltd.


                                By /s/ G. Mary Ruby
                                  -----------------------------------
                                Name:  G. Mary Ruby
                                Title: Secretary


                                By /s/ Edward MacNeil
                                  -----------------------------------
                                Name:  Edward MacNeil
                                Title: Vice President



                                1329507 Ontario Inc.


                                By /s/ G. Mary Ruby
                                  -----------------------------------
                                Name:  G. Mary Ruby
                                Title: Secretary


                                By /s/ Edward MacNeil
                                  -----------------------------------
                                Name:  Edward MacNeil
                                Title: Vice President



                                924689 Ontario Inc.


                                By /s/ G. Mary Ruby
                                  -----------------------------------
                                Name:  G. Mary Ruby
                                Title: Secretary


                                By /s/ Edward MacNeil
                                  -----------------------------------
                                Name:  Edward MacNeil
                                Title: Vice President



                                       9



                                IMAX (Titanica) Ltd.


                                By /s/ G. Mary Ruby
                                  -----------------------------------
                                Name:  G. Mary Ruby
                                Title: Secretary


                                By /s/ Edward MacNeil
                                  -----------------------------------
                                Name:  Edward MacNeil
                                Title: Vice President



                                IMAX (Titanic) Inc.


                                By /s/ G. Mary Ruby
                                  -----------------------------------
                                Name:  G. Mary Ruby
                                Title: Secretary


                                By /s/ Edward MacNeil
                                  -----------------------------------
                                Name:  Edward MacNeil
                                Title: Vice President



                                IMAX Music Ltd.


                                By /s/ G. Mary Ruby
                                  -----------------------------------
                                Name:  G. Mary Ruby
                                Title: Secretary


                                By /s/ Edward MacNeil
                                  -----------------------------------
                                Name:  Edward MacNeil
                                Title: Vice President



                                IMAX Theatre Holding (Brossard) Inc.


                                By /s/ G. Mary Ruby
                                  -----------------------------------
                                Name:  G. Mary Ruby
                                Title: Secretary


                                By /s/ Edward MacNeil
                                  -----------------------------------
                                Name:  Edward MacNeil
                                Title: Vice President




                                       10



                                IMAX Film Holding Co.


                                By /s/ G. Mary Ruby
                                  -----------------------------------
                                Name:  G. Mary Ruby
                                Title: Secretary


                                By /s/ Edward MacNeil
                                  -----------------------------------
                                Name:  Edward MacNeil
                                Title: Vice President



                                IMAX Indianapolis LLC


                                By /s/ G. Mary Ruby
                                  -----------------------------------
                                Name:  G. Mary Ruby
                                Title: Secretary


                                By /s/ Edward MacNeil
                                  -----------------------------------
                                Name:  Edward MacNeil
                                Title: Vice President



                                IMAX Pictures Corporation


                                By /s/ G. Mary Ruby
                                  -----------------------------------
                                Name:  G. Mary Ruby
                                Title: Secretary


                                By /s/ Edward MacNeil
                                  -----------------------------------
                                Name:  Edward MacNeil
                                Title: Vice President



                                Immersive Entertainment Inc.


                                By /s/ G. Mary Ruby
                                  -----------------------------------
                                Name:  G. Mary Ruby
                                Title: Secretary


                                By /s/ Edward MacNeil
                                  -----------------------------------
                                Name:  Edward MacNeil
                                Title: Vice President



                                       11



                                IMAX Providence General Partner Co.


                                By /s/ G. Mary Ruby
                                  -----------------------------------
                                Name:  G. Mary Ruby
                                Title: Secretary


                                By /s/ Edward MacNeil
                                  -----------------------------------
                                Name:  Edward MacNeil
                                Title: Vice President



                                IMAX Providence Limited Partner Co.


                                By /s/ G. Mary Ruby
                                  -----------------------------------
                                Name:  G. Mary Ruby
                                Title: Secretary


                                By /s/ Edward MacNeil
                                  -----------------------------------
                                Name:  Edward MacNeil
                                Title: Vice President



                                IMAX Theatre Holding (California I) Co.


                                By /s/ G. Mary Ruby
                                  -----------------------------------
                                Name:  G. Mary Ruby
                                Title: Secretary


                                By /s/ Edward MacNeil
                                  -----------------------------------
                                Name:  Edward MacNeil
                                Title: Vice President



                                IMAX Theatre Holding (California II) Co.


                                By /s/ G. Mary Ruby
                                  -----------------------------------
                                Name:  G. Mary Ruby
                                Title: Secretary


                                By /s/ Edward MacNeil
                                  -----------------------------------
                                Name:  Edward MacNeil
                                Title: Vice President



                                       12



                                IMAX Theatre Holding (Nyack I) Co.


                                By /s/ G. Mary Ruby
                                  -----------------------------------
                                Name:  G. Mary Ruby
                                Title: Secretary


                                By /s/ Edward MacNeil
                                  -----------------------------------
                                Name:  Edward MacNeil
                                Title: Vice President



                                IMAX Theatre Holding (Nyack II) Co.


                                By /s/ G. Mary Ruby
                                  -----------------------------------
                                Name:  G. Mary Ruby
                                Title: Secretary


                                By /s/ Edward MacNeil
                                  -----------------------------------
                                Name:  Edward MacNeil
                                Title: Vice President



                                IMAX Theatre Management (Scottsdale), Inc.


                                By /s/ G. Mary Ruby
                                  -----------------------------------
                                Name:  G. Mary Ruby
                                Title: Secretary


                                By /s/ Edward MacNeil
                                  -----------------------------------
                                Name:  Edward MacNeil
                                Title: Vice President



                                Panda Productions Inc.


                                By /s/ G. Mary Ruby
                                  -----------------------------------
                                Name:  G. Mary Ruby
                                Title: Secretary


                                By /s/ Edward MacNeil
                                  -----------------------------------
                                Name:  Edward MacNeil
                                Title: Vice President



                                       13



                                Strategic Sponsorship Corporation


                                By /s/ G. Mary Ruby
                                  -----------------------------------
                                Name:  G. Mary Ruby
                                Title: Secretary


                                By /s/ Edward MacNeil
                                  -----------------------------------
                                Name:  Edward MacNeil
                                Title: Vice President



                                Tantus II Films Ltd.


                                By /s/ G. Mary Ruby
                                  -----------------------------------
                                Name:  G. Mary Ruby
                                Title: Secretary


                                By /s/ Edward MacNeil
                                  -----------------------------------
                                Name:  Edward MacNeil
                                Title: Vice President



                                RPM Pictures Ltd.


                                By /s/ G. Mary Ruby
                                  -----------------------------------
                                Name:  G. Mary Ruby
                                Title: Secretary


                                By /s/ Edward MacNeil
                                  -----------------------------------
                                Name:  Edward MacNeil
                                Title: Vice President



                                GUARANTEEING SUBSIDIARIES:



                                Taurus-Littrow Productions Inc.



                                By /s/ G. Mary Ruby
                                  -----------------------------------
                                Name:  G. Mary Ruby
                                Title: Secretary


                                By /s/ Edward MacNeil
                                  -----------------------------------
                                Name:  Edward MacNeil
                                Title: Vice President



                                       14



                                3D Sea II Ltd.



                                By /s/ G. Mary Ruby
                                  -----------------------------------
                                Name:  G. Mary Ruby
                                Title: Secretary


                                By /s/ Edward MacNeil
                                  -----------------------------------
                                Name:  Edward MacNeil
                                Title: Vice President


                                       15



                                TRUSTEE:

                                U.S. Bank National Association,
                                        As Trustee


                                By: /s/ Frank P. Leslie III
                                   ---------------------------------------
                                Name:  Frank P. Leslie III
                                Title: Vice President




                                       16