Problem with the Media creation tool

I download the Windows image twice via the media creation tool. The file sizes though same, had different hashes(SHA1). If the images are identical, why the different hashes. Needless to say, the hashes don't obviously match with their MSDN counterpart.
Why is this happening?

The hashes won't match because the date modified for the install.esd file contained within the iso changes to the date/time the file was downloaded by the MCT.

Same file size because the date/time occupies the same number of bytes. Different hash sum because those bytes are different.