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                                                                    Exhibit 10.3

                                                                  EXECUTION COPY

                               VOTING AGREEMENT

     VOTING AGREEMENT (this "Agreement") dated as of June 29, 2001, among
                             ---------
INSIGHT HEALTH SERVICES HOLDINGS CORP., a Delaware corporation ("Parent"), JWCH
                                                                 ------
MERGER CORP., a Delaware corporation and wholly-owned subsidiary of Parent
("Acquisition") and GE FUND, a New York corporation (the "Stockholder").
 ------------                                             -----------

     WHEREAS, Parent, Acquisition and InSight Health Services Corp., a Delaware
corporation (the "Company"), have entered into an Agreement and Plan of Merger,
                  -------
dated as of the date hereof (the "Merger Agreement"; capitalized terms used but
                                  ----------------
not defined herein shall have the meanings set forth in the Merger Agreement),
whereby Acquisition will merge with and into the Company and the Company shall
become the wholly-owned subsidiary of Parent (the "Merger"), upon the terms and
                                                   ------
subject to the conditions set forth in the Merger Agreement;

     WHEREAS, the Stockholder beneficially owns 10,948 shares of convertible
preferred stock, Series C of the Company, par value $0.001 per share (the
"Series C Preferred Stock"), convertible in the aggregate into 130,722.4 shares
 -------------------------
of convertible preferred stock, Series D of the Company, par value $0.001 per
share (the "Series D Preferred Stock");
            ------------------------

     WHEREAS, pursuant to this Agreement the Stockholder agrees to (i) elect to
convert all of the Series C Preferred Stock that it owns into 130,722.4 shares
of Series D Preferred Stock pursuant to the terms thereof prior to the record
date for the Approval Events (as defined below), (ii) vote in favor of the
Merger and the adoption by the Company of the Merger Agreement, and (iii)
convert all of the aforementioned 130,722.4 shares of Series D Preferred Stock
into shares of Company Common Stock prior to the Closing; and

     WHEREAS, as a condition to and in consideration of the willingness of
Parent and Acquisition to enter into the Merger Agreement, the Stockholder has
agreed to enter into this Agreement.

     NOW, THEREFORE, in consideration of the premises and the representations,
warranties and agreements contained herein and other valuable consideration, the
receipt and sufficiency of which is hereby acknowledged, the parties hereto
agree as follows:

     1.     Representations and Warranties of the Stockholder. The Stockholder
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hereby represents and warrants to Parent and Acquisition as follows:

     (a)    Authority: No Conflicts. The Stockholder is a corporation duly
organized, validly existing and in good standing under the laws of the State of
New York and has the requisite corporate power and authority to execute and
deliver this Agreement, to perform its obligations hereunder and to consummate
the transactions contemplated hereby. This Agreement has been duly authorized,
executed and delivered by and on behalf of the Stockholder and constitutes a
legal, valid and binding obligation of the Stockholder, enforceable in
accordance with its terms (except to the extent that enforcement may be affected
by laws relating to
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bankruptcy, reorganization, insolvency, and creditors' rights and by the
availability of injunctive relief, specific performance and other equitable
remedies). No filing with, and no permit, authorization, consent or approval of,
any Governmental Entity or any other person is necessary for the execution and
delivery of this Agreement by and on behalf of the Stockholder and the
consummation by the Stockholder of the transactions contemplated hereby. None of
the execution and delivery of this Agreement by and on behalf of the
Stockholder, the consummation of the transactions contemplated hereby and
compliance with the terms hereof by the Stockholder will conflict with, or
result in any violation of, or default (with or without notice or lapse of time
or both) under any provision of, the Stockholder's certificate of incorporation
or bylaws or organizational documents, any trust agreement, loan or credit
agreement, note, bond, mortgage, indenture, lease or other agreement,
instrument, permit, concession, franchise, license, judgment, order, notice,
decree, statute, law, ordinance, rule or regulation applicable to the
Stockholder or to the Stockholder's property or assets.

          (b)    The Subject Shares. The Stockholder is the beneficial owner of
the Series C Preferred Stock (the "Subject Shares"; provided that the Subject
                                   --------------
Shares shall also include any and all securities issuable in respect of the
Series C Preferred Stock or Series D Preferred Stock upon conversion thereof, as
applicable) and has, and throughout the term of this Agreement will have, good
and marketable title to the Subject Shares free and clear of all Liens. The
Stockholder does not own, of record or beneficially, any shares of capital stock
of the Company or securities convertible into or exchangeable for shares of
capital stock of the Company, other than the Subject Shares. The Stockholder has
the sole right and power to vote and dispose of the Subject Shares, and none of
the Subject Shares is subject to any irrevocable proxy, power of attorney,
voting trust or other agreement, arrangement or restriction with respect to the
voting or transfer (other than the provisions of the Securities Act or state
securities laws) of any of the Subject Shares, except as contemplated by this
Agreement.

          2.     Representations and Warranties of Parent and Acquisition.
                 --------------------------------------------------------
Parent and Acquisition hereby represent and warrant to the Stockholder that each
is a corporation duly organized, validly existing and in good standing under the
laws of the State of Delaware and has the requisite corporate power and
authority to execute and deliver this Agreement, to perform its obligations
hereunder and to consummate the transactions contemplated hereby. This Agreement
has been duly authorized, executed and delivered by and on behalf of each of
Parent and Acquisition and constitutes a legal, valid and binding obligation of
each of Parent and Acquisition enforceable in accordance with its terms (except
to the extent that enforcement may be affected by laws relating to bankruptcy,
reorganization, insolvency, and creditors' rights and by the availability of
injunctive relief, specific performance and other equitable remedies). Except
for the filings required under the HSR Act and the Exchange Act, exemptive
filings under federal and state securities laws in connection with equity
investments in Parent and the filing of the Certificate of Merger with the
Secretary of State of the State of Delaware, (i) no filing with, and no permit,
authorization, consent or approval of, any Governmental Entity or any other
Person is necessary for the execution of this Agreement by and on behalf of each
of Parent and Acquisition and the consummation by Parent and Acquisition of the
transactions contemplated hereby, and (ii) none of the execution and delivery of
this Agreement by Parent and Acquisition, the consummation of the transactions
contemplated hereby nor the compliance with the terms

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hereof by Parent and Acquisition will conflict with, or result in any violation
of, or default (with or without notice or lapse of time or both) under any
provision of, their respective certificate of incorporation or bylaws, any trust
agreement, loan or credit agreement, note, bond, mortgage, indenture, lease or
other agreement, instrument, permit, concession, franchise, license, judgment,
order, notice, decree, statute, law, ordinance, rule or regulation applicable to
Parent or Acquisition, as the case may be, or to Parent's or Acquisition's,
property or assets, as the case may be.

          3.     Covenants of the Stockholder. Until the termination of this
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Agreement in accordance with Section 8 hereof, the Stockholder agrees as
follows:

          (a)    Voting of Subject Shares. At any meeting of stockholders of the
Company called to vote upon the approval of the Merger, the Merger Agreement and
the transactions contemplated therein or at any adjournment thereof or in any
other circumstances upon which a vote or other approval with respect to the
Merger, the Merger Agreement and the transactions contemplated therein is sought
(the "Approval Events"), the Stockholder shall vote all of the Subject Shares at
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the time of such meeting or adjournment in favor of the Merger, the adoption by
the Company of the Merger Agreement and the approval of the terms thereof and
each of the other transactions contemplated by the Merger Agreement.

          (b)    Irrevocable Proxy. The Stockholder hereby grants to and
appoints Parent (and each officer of Parent designated by Parent) its proxy and
attorney-in-fact (with full power of substitution) to vote all of the Subject
Shares as indicated in Section 3(a) above. The Stockholder agrees that this
proxy shall be irrevocable during the term of this Agreement and is coupled with
an interest sufficient at law to support an irrevocable power and given to
Parent as an inducement to enter into the Merger Agreement; provided that Parent
may at any time name any other Person as its substituted Proxy to act pursuant
hereto, either as to a specific matter or as to all matters covered herein.
Stockholder agrees to take such further action or execute such other instruments
as may be reasonably requested by Parent or Acquisition to effectuate the intent
of this paragraph (b). The Stockholder hereby revokes any proxy previously
granted by the Stockholder with respect to the Subject Shares.

          (c)    Transfer Restrictions. The Stockholder agrees not to (i) sell,
transfer, pledge, encumber, assign or otherwise dispose of or hypothecate
(including by gift or by contribution or distribution to any trust or similar
instrument or to any beneficiaries of the Stockholder (collectively,
"Transfer")), or enter into any contract, option or other arrangement or
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understanding (including any profit sharing arrangement) with respect to the
Transfer of, any of the Subject Shares other than pursuant to the terms of this
Agreement and the Merger Agreement, (ii) enter into any voting arrangement or
understanding other than this Agreement with respect to the Subject Shares,
whether by proxy, voting agreement or otherwise, or (iii) take any action that
could make any of its representations or warranties contained herein untrue or
incorrect or could have the effect of preventing or disabling the Stockholder
from performing any of its obligations hereunder. The Stockholder further agrees
to take in a timely manner any and all actions (including, without limitation,
delivering the certificates evidencing the Subject Shares to the Company)
reasonably necessary for the Company to affix a legend on the

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certificates evidencing the Subject Shares stating that the Subject Shares are
subject to this Agreement.

          (d)    Appraisal Rights. The Stockholder hereby irrevocably waives any
and all rights which it may have as to appraisal, dissent or any similar or
related matter with respect to the Merger under Section 262 of the General
Corporation Law of the State of Delaware or otherwise.

          (e)    No Solicitation. The Stockholder shall not, and shall use its
reasonable best efforts to cause its directors, officers, employees, attorneys,
accountants or financial advisors or other representatives ("Representatives")
                                                             ---------------
retained by it not to, directly or indirectly through another Person, (i)
solicit, initiate or encourage (including by way of furnishing information), or
take any other action to facilitate, any inquiries or the making of any proposal
that constitutes, or may reasonably be expected to lead to, any Takeover
Proposal, or (ii) participate in any discussions or negotiations regarding any
Takeover Proposal; provided that the foregoing shall not limit or prohibit any
Representative of the Stockholder who is a director of the Company from
exercising his or her fiduciary duty solely as a director of the Company in a
manner consistent with the terms and conditions set forth in the Merger
Agreement.

          4.     Conversion of Subject Shares. In connection with the Merger and
                 ----------------------------
the Merger Agreement, the Stockholder hereby agrees to deliver a Type B
Conversion Notice (as defined in the Certificate of Designation with respect to
the Series C Preferred Stock) electing to (subject to the delivery of a Type B
Conversion Notice with respect to the Series B Preferred Stock) convert all of
the Series C Preferred Stock that it owns into 130,722.4 shares of the Series D
Preferred Stock pursuant to the terms thereof prior to the record date
established by the Company in connection with the Approval Event which would
permit such Stockholder to vote all of such shares held by such Stockholder
after such conversion, irrespective of any voting limitations, in favor of the
Merger, the Merger Agreement and the transactions contemplated therein.

          5.     Conversion of Series D Preferred Stock. Immediately prior to
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the Effective Time, the Stockholder hereby agrees to convert all of the shares
of Series D Preferred Stock then owned by it into shares of Company Common
Stock.

          6.     Additional Shares. Without limiting the provisions of the
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Merger Agreement, in the event (i) of any stock dividend, stock split,
recapitalization, reclassification, combination or exchange of shares of capital
stock of the Company on, of or affecting the Subject Shares or (ii) the
Stockholder becomes the record or beneficial owner of any additional shares of
the capital stock of the Company or other securities entitling the holder
thereof to vote or give consent with respect to the matters set forth in Section
3(a), then the terms of this Agreement shall apply to the shares of capital
stock or other securities of the Company held by the Stockholder immediately
following the effectiveness of the events described in clause (i) or the
Stockholder becoming the record or beneficial owner thereof, as described in
clause (ii), as though they were Subject Shares hereunder. The Stockholder
hereby agrees to promptly notify Parent of the number of any additional shares
of capital stock or other voting securities of the

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Company acquired, of record or beneficially, by the Stockholder, if any, after
the date hereof and prior to the termination of this Agreement pursuant to
Section 8 hereof.

          7.     Officers and Directors. Notwithstanding anything contained to
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the contrary in this Agreement, in the event a Representative is a director or
officer of the Company, nothing in this Agreement is intended or shall be
construed to, require such Representative, solely in his or her capacity as a
director or officer of the Company, to act or fail to act in any manner
inconsistent with (i) his or her fiduciary duties in such capacity and (ii) the
Merger Agreement. Furthermore, no Representative who is or becomes (during the
term hereof) a director or officer of the Company makes any agreement or
understanding herein solely in his or her capacity as a director or officer, and
nothing herein will limit or affect, or give rise to any liability of any
Representative solely in such Person's capacity as a director or officer of the
Company.

          8.     Termination. Except as set forth in the next sentence, this
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Agreement shall terminate, and no party shall have any rights or obligations
hereunder and this Agreement shall become null and void and have no further
effect immediately following the earliest to occur of (x) the Effective Time or
(y) the termination of the Merger Agreement. Nothing in this Section 8 shall
relieve any party of liability for breach of this Agreement.

          9.     Contents of Agreement; Parties in Interest, etc. This Agreement
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and the agreements referred to or contemplated herein set forth the entire
understanding of the parties hereto with respect to the transactions
contemplated hereby and thereby, and, except as set forth in this Agreement and
such other agreements, there are no representations or warranties, express or
implied, made by any party to this Agreement with respect to the subject matter
of this Agreement. Any and all previous agreements and understandings between or
among the parties regarding the subject matter hereof, whether written or oral,
are superseded by this Agreement and the agreements referred to or contemplated
herein.

          10.    Assignment and Binding Effect. Neither this Agreement nor the
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rights and obligations hereunder may be assigned by any of the parties hereto
without the prior written consent of the other parties hereto; provided, that
Parent and/or Acquisition may assign its rights and obligations under this
Agreement to any directly or indirectly wholly-owned Subsidiary of Parent, upon
written notice to the Stockholder if the assignee shall assume the obligations
of Parent and/or Acquisition hereunder. Subject to the foregoing, all the terms
and provisions of this Agreement shall be binding upon and inure to the benefit
of and be enforceable by the respective successors and assigns of the parties
hereto.

          11.    Notices. Any notice, request, demand, waiver, consent,
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approval, or other communication which is required or permitted to be given to
any party hereunder shall be in writing and shall be deemed given only if
delivered to the party personally or sent to the party by facsimile transmission
(promptly followed by a hard copy delivered in accordance with this Section 11
or by registered or certified mail (return receipt requested), with postage and
registration or certification fees thereon prepaid, addressed to the party at
its address set forth below:

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               If to Parent or Acquisition:
               ---------------------------

               c/o J.W. Childs Associates, L.P.
               One Federal Street, 21st Floor
               Boston, MA 02110
               Attention: Edward D. Yun
               Facsimile No.: (617) 753-1101

               and

               c/o The Halifax Group, L.L.C.
               1133 Connecticut Avenue, N.W.
               Suite 700
               Washington, D.C.  20036
               Attention: David W. Dupree
               Facsimile No.: (202) 296-7133

               with a copy to:

               Kaye Scholer LLP
               425 Park Avenue
               New York, New York  10022
               Attention: Stephen C. Koval, Esq.
               Facsimile No.: (212) 836-8689

               If to the Stockholder:
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               GE Fund
               c/o General Electric Company
               3135 Easton Turnpike
               Fairfield, CT 06431
               Attn: Jerome C. Marcus
               Facsimile: 203-357-6527

               with a copy to:

               GE Fund
               c/o General Electric Company
               3135 Easton Turnpike
               Fairfield, CT 06431
               Attn: Eliza W. Fraser
               Facsimile: 203-373-3079

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               and

               Gibson, Dunn & Crutcher LLP
               333 South Grand Avenue
               Los Angeles, CA 90071
               Attn: Linda Curtis, Esq.
               Facsimile: 213-229-6582

or to such other address or Person as any party may have specified in a notice
duly given to the other party as provided herein.  Such notice, request, demand,
waiver, consent, approval or other communication will be deemed to have been
given as of the date so delivered, telegraphed or mailed.

          12.    Amendment. This Agreement may not be amended except by an
                 ---------
instrument in writing signed by all of the parties hereto.

          13.    Extensions; Waiver. Any party to this Agreement may (a) extend
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the time for the performance of any of the obligations or other acts of the
other parties, (b) waive any inaccuracies in the representations and warranties
of the other parties contained in this Agreement or in any document delivered
pursuant to this Agreement, or (c) waive compliance by the other party with any
of the agreements or conditions contained in this Agreement. Any agreement on
the part of a party to any such extension or waiver shall be valid only if set
forth in an instrument in writing signed on behalf of such party. The failure of
any party to this Agreement to assert any of its rights under this Agreement or
otherwise shall not constitute a waiver of such rights.

          14.    Governing Law. This Agreement shall be governed by and
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interpreted and enforced in accordance with the laws of the State of Delaware,
without regard to the conflicts of law principles thereof.

          15.    No Benefit to Others. The representations, warranties,
                 --------------------
covenants and agreements contained in this Agreement are for the sole benefit of
the parties hereto, and their respective successors and assigns, and they shall
not be construed as conferring, and are not intended to confer, any rights on
any other Person.

          16.    Severability. If any term or other provision of this Agreement
                 ------------
is determined to be invalid, illegal or incapable of being enforced by any rule
of law or public policy, all other terms and provisions of the Agreement shall
remain in full force and effect. Upon such determination, the parties hereto
shall negotiate in good faith to modify this Agreement so as to give effect to
the original intent of the parties to the fullest extent permitted by applicable
law.

          17.    Section Headings. All section headings are for convenience only
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and shall in no way modify or restrict any of the terms or provisions hereof.

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          18.    Counterparts. This Agreement may be executed in two or more
                 ------------
counterparts, each of which shall be deemed an original, and the Stockholder,
Acquisition and Parent may become a party hereto by executing a counterpart
hereof. This Agreement and any counterpart so executed shall be deemed to be one
and the same instrument.

                           [Signature Page Follows]

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     IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
duly executed as of the date first written above.


                                     INSIGHT HEALTH SERVICES HOLDINGS CORP.


                                     By: /s/ Edward D. Yun
                                         ________________________
                                         Name:  Edward D. Yun
                                         Title: President


                                     JWCH MERGER CORP.


                                     By: /s/ Edward D. Yun
                                         ________________________
                                         Name:  Edward D. Yun
                                         Title: President
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     IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
duly executed as of the date first written above.


                                GE FUND


                                By: /s/ Jerome C. Marcus
                                    ________________________
                                    Name:  Jerome C. Marcus
                                    Title: Attorney-In-Fact