did you try committing it? make sure to commit it,
Also, you can try to add an image widget and show the uploaded image, but refreshing the grid itself, this way, you will always have a preview of the uploaded image on the page.
Let me know, if you have any issues,
Hope it helps!!
I think no option in configuration to do that but you can hide it always and add list view or data view containing images or files (image widget or file viewer widget could help you) instead of that