Thank you for the reply.
Unfortunately I need to use an external image source of the image control in the report, and the values are taken from the field of the dataset.
Try to change the dataset query to this:
SELECT
ImageTest.ID
,ImageTest.Name
,ImageTest.Photo
,'http://dummyimage.com/200x100/292929/e3e3e3&text=DummyText' as imageurl
FROM
ImageTest
and set the image source as external.
Thank you.