Timestamp of file upload

Hello,

Does anyone know if it possible to find the last modified time of a file that has just been uploaded. I.e. I save a file on my computer at Friday 4th July 1.40pm. I then upload this file 1 hour later. I have tried

File.mtime(photo.path)

but this only returns the timestamp of when the file was saved as a temp file (i.e. 2.40pm). Is it possible to find the original last modified time (1.40pm)

Hope someone can help

Thanks

Iain