can't export correct images using script tool, works fine in regular script

Hi,

I am having trouble getting my script tool to export the currentTime and endTime with a hard coded interval of 1 hours.

It works fine in my regular script without parameters but when I set the below code the images arent exported

mxd= (GetParameterAsText(0))
currentTime = GetParameter(1)
endTime = GetParameter(2)

In the script tool the data type is set to date. I'm not sure what the problem is. The user can specify the date and time in the script tool but after the tool runs and is complete the exported images have not been interated correctly with the specified hard coded 1 hour interval.

Any help?

Thank you