Pulling an image from a field with page.find


I want to use the page.find function to pull an image from a field on another page but I can’t get it to work - it works if I put the image path directly into the tag, but I can’t work out the syntax (or if its possible) to pull from the tag’s value - for example:

I have this in my page header:

        name: header-bg.jpg
        path: user/pages/images/header-bg.jpg

This works

{{ page.find('/images').media['header-bg.jpg'].cropZoom(1400,450).quality(100).url }}

But this doesn’t (and I don’t understand it well enough to work out the right syntax):

{{ page.find('/images').page.header.bg[path].cropZoom(1400,450).quality(100).url }}

I have tried about 20 different variations but I can’t work out the right syntax - is there a way to pull the image from that field on that page without specifying the exact filename?