How to automatically open image (file url) in lightbox?

Currently when i add images to blog post i always choose to insert the large or medium size image, and i set the image link to the file url (full original size image)… When someone click on the image they sort of “leave” the site and go to the file url, instead i’d like for the image to open in a lightbox, ideally the lightbox would adapt to the screen resolution and resize the image as needed because some of the images can be quite large.

Any fast lightweight plugins that do this?

I found some plugins that could almost do this, the issue is that the images link need to be set to “attachment page”, but mine are set to the file url, i would like to avoid going into hundreds of post to change all of the image links…or having to go in each lost to add some special shortcodes etc…

Any help appreciated,
Thx!