I have finally decided to upload this one to AP. I hope that it won't be denied cold-heartedly and support it with explanation.
The wallpaper is by me, as commonly recognized in waller communities - the characters are extracted from scans. I paid attention to this process to ensure the best quality. Rabi~en~Rose is from a different scan than Puchiko, of course, so I had to make two extractions. Besides that, the brightness is also adjusted.
As for the background. I wanted to make a hanabi scene from the start. I tried several different approaches and this set of fireworks finally looked OK. The rest of the background is made of a trees photo, which was taken during the day, but altered to be suitable as trees at night. I tried to use as subtle filters as possible, to not to distort it awkwardly, just to imitate a lower resolution of the human eye at night. The grass is a plain brush, with some flowers added, of course.
If you think that the characters are too bright, please bear with me: How would it look if you used a camera at night to picture people, lanterns shining against you? I'm not even as good as an amateur at this, so sorry if I should have done an all-day scene.
A good point I believe is that the BG is an all-around photo manipulation, with components barely comparable to their sources.
And I'm actually using it as my wallpaper, so the manufacturer->consumer thing doesn't apply here.
The wallpaper was originally done in 2048x1536 for the purpose of printing, reachable by the link "More resolutions".
EDIT: The link is gone with version 5, so here it is again: http://zdenek.szm.com/gallery/zwz_my_zwz34.htm