Master Image Creator Security Issue

Hello,
This has been talked about regarding previous versions but there wasn't really an acceptable solution in my eyes.

Scenario:
I boot off a USB disk to create a master image. When trying to save to a network location I can see computers but no shares beneath them. If I type in a UNC path to the share and try ans save a new image I get a message saying "You do not have enough privileges to create the file".

Based on a previous forum post about an older version, I gave 'everyone' rights to the share and tried to save a file to it. I'm then prompted with a window asking for my credentials which then work and I can create an image.

The issue is that granting 'everyone' read / write access to the share is unacceptable as it creates a security risk.

Does anyone know how to make the master image creator and the deployment agent prompt for a user / password if 'everyone' doesn't have rights to the share folder?

Thanks!