basIt’s not that hard to use an other image, it only needs some smart fiddling. If you use a plugin like this: https://wordpress.org/plugins/add-url-slugs-as-body-classes/, each page has his own css class.
With a background image, this is the source code:
<div class=”header-main page-title-color” style=”background-image:url(‘http://*****/wp-content/uploads/2015/07/*****.jpg’);” >
Without a background image:
<div class=”header-main page-title-color”>
Using the mentioned plugin, we can add an extra class with the page, like this:
<div class=”header-main page-title-color slug“>
So, in the stylesheet, you could try something this:
.slug div.header-main .page-title-color{
background-image:url(‘http://*****/wp-content/uploads/2015/07/other-image.jpg’) !important;
}
I did not get it working, but don’t have the time to try this extensively, so please let me know the results!