When you hover your mouse over the edit button a dropdown will pop down with options for properties, design, permissions, etc Click properties, click custom attribute from the top tabs on the properties menu. Scroll down until you find the attribute "background image". Click it and than click it again and add your image.

I don't think there is a default background image custom attribute for concrete5, I think it had to be either manually added or set up as part of a package/theme. The theme you use has to be set up to use the background image selected too.

Here's some code I pasted last year, it should still work for 5.5. (last post in thread)

http://www.concrete5.org/community/forums/customizing_c5/page-backg...

I think I see what your after now after reading it again, and I think your problem is user created pages like forum posts are being created with the themes default image. There are several ways to go about taking care of that and background images.

Most photo background themes have the default background image as an option in theme options. Access this by going to dashbpard-->pages & themes category-->themes
than click the customize button for the theme you are using. There should be an option here for default image.

If your problem is that users are creating pages such as forum posts and its only these that you are worried about you can set the background image for that page type by using page type defaults. Searching page type defaults in the search will come up with how tos on doing this.

If your theme lacks the attribute than either Messuva's method or the one found here should both work in adding it.

http://www.concrete5.org/community/forums/themes/customising-theme-...

If the above doesn't work for you than your theme will have a file for the background image that you can change ex theme/images/default_bg.jpg on your server. You can replace this for the image you prefer by placing the prefered image in its place, but you need to be sure the name is the same ex. default_bg.jpg

Ekko said:
"When you hover your mouse over the edit button a dropdown will pop down with options for properties, design, permissions, etc Click properties, click custom attribute from the top tabs on the properties menu. Scroll down until you find the attribute "background image".

BUT ... there is no such attribute on the properties menu. This answer is dead wrong.


Ekko then said:
"Most photo background themes have the default background image as an option in theme options. Access this by going to dashbpard-->pages & themes category-->themes
than click the customize button for the theme you are using. There should be an option here for default image."

BUT ... that's also dead wrong. I have Green Salad, Plain Yogurt and Dark Chocolate, and NONE of them have an option for default image.

How, pray tell, if it's not top secret, do I change the header images in concrete5?

Actually, i have created my custom theme, and in the content pages i just want to change background image in every page. For example, for the about us page i want to use another image than the page of references.

The link I posted earlier should work for this.

Or if you want to save some time/stress, there are quite a few background image add-ons in the marketplace:
http://www.concrete5.org/marketplace/addons/-/view/?submit_search=1...

Developed a simple addon to do this for you across whole site, and free! :) -http://www.concrete5.org/marketplace/addons/background-image/...