Since you're still experiencing the same issue with pictures I merged your two threads together to help keep the information provided in the same forum thread.

The background picture for the lock screen can be changed from the Bing image of the day to a custom picture by performing the following steps.

1. Open the phone Settings.
2. Select the Lock+Wallpaper option under System.
3. In the first drop down menu; change the option from Bing to picture.
4. Select the change picture option to select a photo.
5. After these steps are completed your photo background should be changed on the lock screen.

Please let us know if you have any additional questions. Thank you for posting to the Microsoft Community!

Regards,
Manpreet Singh

Hello Forum Community

I'm new here and would like me as Max imagine

I am since short time in switched from Samsung to Nokia .
Now my question is , how can I make my Nokia Lumia 630
the Sperrbilschirm change .
It's such a boring image .
My wife has the same Nokia , it has already been a very
different picture than I do . Also looks better .
Can that ever change and if so where and how ?

Greetings Max