As the title suggests I will give advice about what I'm asked, but it's art advice. I don't want other questions here that have nothing to do with the process of creating art. You can ask me using Formspring, and I'll make a tutorial for your question. I'll combine questions if necessary, like 'how do I extract?' and 'how do I use curves to extract?'.
Bear in mind that I use Photoshop so if you want specific advice that can be done with a certain type of program, it has to be Photoshop. I will give advice for more categories, it doesn't have to be strictly technical. For example, how do I combine the right pictures? how do I play with the colors? and so on.

Formspring to ask: SakuraDust

Tags for amazing Backgrounds

I decided to share some tags (you veterans know them already) for categories where you can find amazing backgrounds for your wallpapers. The tags are on MT so I suggest making an account there because not all scans are available to download for non-members.

The tags are (they're links, click on them):

CG Scans

  • they have high quality, complex backgrounds with a variety of scenes from sunsets to churches
  • downside: you'll find a lot of ecchi and scans where the character covers the whole background, but there's a gold mine hidden, I assure you
  • examples:

External Image External Image External Image External Image

5 Centimeters Per Second

  • this type of background is beautiful, but tricky because it fits with a certain type of coloring style
  • cell shaded characters often look misplaced within them
  • I suggest manga scans, not anime, with a style that resembles: Boku wa Tomodachi ga Sukunai
  • for textures grunge should work with cities and cherry trees, bokeh with sky, but don't abuse it

Tales from Earthsea

  • this is a more complex scan category that works well with the warrior type of character
  • complex backgrounds yet again with interesting sketches of castles and diverse scenery that could benefit even experienced wallers who need a reference

redjuice

  • definitely abstract backgrounds that fit well with Vocaloid, Evangelion and characters in futuristic outfits

Kina Kazuharu

Pixiv

Alphonse

Dhiea

  • works good with Victorian scans
  • best for the fairytale theme

Vania600

(I have some questions I'll answer in other posts, they require lots of screencaps)

Mangaka or Fanartist? Best way to figure it out

It's been crazy ever since Zerochan put fanartists under the mangaka tag.
Here's an easy way to not use fanart and avoid getting your works deleted.

First of all check the tags for the following: Pixiv, Fanart, Deviantart.com
These are all sources and although they are there I see lots of walls who credit pictures that contain them.

Anyway, the ways to see if the pictures who don't have these tags are fanart or not are simple:

1) You click the Mangaka on Zerochan.
It should open to a page with all the works of that person and in the right there's the link to the Deviantart or Pixiv page.

2) You search the Mangaka on Minitokyo.
If there's something perfect on Minitokyo, it's the tags. If it's posted on Minitokyo then the mangaka is official. Many official mangaka have a Pixiv page, but if the works are on Minitokyo as well then they're safe to use.
External Image

How to Combine Images

There are a few things you need to consider when choosing your images:

1) Consider the character's personality and emotions
- for example if you want to make a wall with Hitsugaya, don't pick a background with flowers and petals, it doesn't fit with his personality
- if the character is crying and is obviously sad, not a happy cry, don't choose a joyful background filled with happiness and rainbows
- in order to emphasize the emotions, the background must mirror the character/s
For example:
* this scan goes very well with this scan (the colors fit and candy are Ciel's favorites, fit him as character)
* but it would look horrible with this one (wrong era and colors too dark)

2) Don't use opposing colors
- the pictures you combine must have colors in common, or colors that go well together; a serious wallpaper shouldn't have purple, green and yellow as the main scheme
- even the funky walls filled with a big number of crazy hues have colors in common which is why the flow well together (example)
- don't use colors uncharacteristic to the character, unless it's a funky wall
For example:
* this scan goes great with this one
* but not so much with this (too orange)

3) The images mustn't have entirely different execution styles
- if you want to use a vector, don't choose a background that looks entirely painted, there's no blending, it excludes the character

4) Match the outfit
- don't pick a Victorian castle if your character wears a modern punk outfit
- you could create a contrast if the character looks amazed, as if he stepped in another world, then yes, two different era images could go well together

Tricks to match the colors:

If you really want to use images that don't have friendly colors, the best way to make them work is to play with the saturation of the brightest one. Lower its Saturation a bit, after that sometimes it's needed to increase the Contrast a bit.
After you're done color playing, I strongly suggest Photo Filter (Photoshop has it, I'm not sure about others). Pick the dominant color in your wall and set it as Filter at what intensity you want. It should equal the colors a bit, enough to make then go better.
If you don't have Photoshop simply fill a layer with the dominant color and play with blending modes until you reach the wanted result.

Don't be shy to use Renders

I've noticed that less and less people use already extracted, cleaned, to sum it up, beautiful renders. Instead, they prefer to post walls with their own low quality and poorly extracted ones.

Using already extracted images isn't something to be shy about, it doesn't label you as 'noob who can't even extract'. Quite the opposite, your own messy extractions label you so. Renders are mostly high quality and very convenient.
To be a beginner and have high quality walls is something I personally admire, even if the vector/render is made by someone else, the result matters.

It doesn't mean that you are prohibited to learn, but keep your experiments at home. You're free to try rendering as much as you want till you perfect the technique, or even call for help using World posts or the Sandbox at Minitokyo, but posting a poor work just because you're too stubborn is insulting to the audience.

Be a mad scientist for a bit, keep working, keep improving but don't let the world know the final result until it's something you can truly grab their hearts with.

Don't try sites like Planet Renders or Renders-Graphiques, it's full of ripped vectors, I saw some of mine there and I'm sure there are more.
Here are some amazing, legit sites with renders.

Animepaper (the vectors now don't cost any papers to download!)
EGAO! Distant Destiny (I guarantee the quality)
Celestial Star (the site I used when I began walling)

Work hard guys and remember, the ones who create renders and vectors for you to use are trying to help you get better!

Submitting on Minitokyo

I noticed how many users from theO post on MT lately. I don't want to be rude but I don't see any other way around this, so to say it bluntly, don't.
MT standards are high, and to be honest compared to how they were once, now they're way lower, but still not low enough for most theO walls submitted there.

I used to always criticize issues such as extraction or quality, but I ultimately gave up, not because I calmed down and don't want to anymore, but because no one listens to me. No one tries to improve the pixelated quality or the horrible extraction just because I advise them to. TheO is a site mostly for amateurs and it annoys me to see that they are content with their level and refuse to improve.

But back at MT, no matter how awesome you think your wall is, for MT is deletion material. Blurriness, bad extraction or low effort composition are deleted on the spot.

Here are some tips:

Extraction - Don't use Magic Wand!
It leaves behind horribly jagged surfaces and it messes with the lineart as well. I saw that it's often corrected with Smudge, it doesn't look good, especially on sharp quality scans.
The perfect tool for extraction is Pen Tool, it gets a perfect job done and very fast. I know how tempting it is to extract with the Magic Wand when you have lots of hair strands, but do control yourselves, Pen Tool makes the extraction look perfect, if used patiently!

Quality
The quality is most likely the biggest reason walls are deleted from MT and even though here a bad quality wall gets comments such as 'kawaii desu~' it doesn't mean it looks good!
I use Photoshop so I'm not familiar with other programs' saving options, but for those who use PS, when saving do it at the highest level for quality, 12. When saving a window pops and it has a 1-12 bar for quality check. Stretch it till the end, 12 is perfect quality!
Other popular ways of busting the quality:

1) Don't over-resize!
The pixels look horrible afterward and no matter how much you filter it, the result only gets worse! Never, ever try to make a tiny 500x600 picture into one that would fit into a 1600x1200 wall, unless you plan on vectoring it.

2) Avoid resizing brushes!
Brushes are complicated to use since they rarely look good when resized no matter in what sense, to make them bigger or smaller. When using brushes try your best to use them at their given size.

3) Resize huge textures!
Very big textures often have questionable quality so try to make them smaller. Don't worry, unlike brushes, they will look better and the quality issues will disappear.

Composition
Effortless layouts are frowned upon! Don't just add some brushes a render and call it a day. The background needs to be complex and high quality for a wall to look good! Take elements from many other scans, connect them with brushes if you want, but don't ever leave a wall with a brushes only background, it will be justifiably deleted for low effort. No one cares if you spent hours on arranging those brushes, the result matters, if it looks poor, then no second chance for it.

Ghosting
Is a very popular way to get lazy with the background. You just blend a character in the back, add some text and the work is done. Not really! Ghosting is complicated and unless it's made into a context, to illustrate memories or feelings and such, it's just thought of as a way to get it over with the background.

No need to say that collages or screencaps aren't allowed at all, right?

These are the Minitokyo and Animepaper standards, they are high, well designed, and for those with no will to improve, impossible to follow!
The mods on MT are very kind and often explain what to do to a wall before it's acceptable for submission, but I strongly suggest the Sandbox [link]. It's a section where you post a work in progress and ask for advice on it. It's easier to improve like that.

Posting deletion worthy walls only serves in making the mods' jobs harder. Deciding to post on MT is a big step in a waller's life!
To get MT passing grades means almost becoming pro.

Think about these issues and fix them before posting walls on high demand sites.
Check this link for EDD tutorials on vectors and extractions [link] (learn those by heart and practice like crazy).

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