Select Distinct by an Image Field

i have an interesting question for you guys.

Code:

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SELECT  S.SCHOOLID AS [SCHOOLID],S.SCHOOLNAME AS [SCHOOLNAME],SP.PHOTO AS [PHOTO]
FROM SCHOOLPHOTO SP
INNER JOIN SCHOOL S
ON SP.SCHOOLID = SP.SCHOOLID
WHERE S.SCHOOLID  IN (SELECT SCHOOLID FROM #SCHOOLS)

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the Photo Field is an Image Datatype Field, i now you can use them in a Distinct or group by , How can i go by have that field there without casting it , because if i cast it it will not work together in Silverlight or any other image control.

Thanks