Are you tired of being constricted to the measly 800 x 450px size of Art Academy? Are you tired of inspecting the element of Miiverse JUST to get your artwork into your computer? Well, you're in LUCK. There's an app for that!
1. Open Art Academy on Miiverse.
2. Open your artwork, as if you were gonna paint it some more.
3. Open the Wii U menu, and go into the browser.
4. Open your email and send yo'self a file attachment! You can attach what's on the screen at the moment, which will be Art Academy's artwork. A nice 1240 x 700 jpeg file will be sent to your email!
5. Be happy.
Props to user Holly for having figured this out in Imgur and spreading the word. Miiverse artists deserve to have a full sized artwork, even if it isn't as big as it can be.
Try it out, and comment your results.
(Some editing MAY be required, depending on what TV you have. Results may vary).
EDIT: Ok, so. A few weeks ago I had a theory about Art Academy's real resolution: The size you see on the gamepad is the actual exporting resolution for Miiverse, which is roughly some lame 800 x 450 px. When you ZOOM in Art Academy you can see a beastly size, that you CAN'T export. Making a basic calculation in Photoshop, I estimated the real Art Academy artwork's size to be around 1800 x 1000 px. I don't know about some of you, but if I invest 15+ hours on an artwork, I like to have it in the resolution I intended it to be; so I got discouraged and shared my unfinished Metroid pic.
Thanks to the work-around, you can recover a decent 1240 x 700 px resolution. That's good, but not as good as it could be... And that's when I tried a very alternative method:
1. Open Art Academy, and open your artwork. Once opened, ZOOM in on the artwork.
2. Open the Wii U menu.
3. Following the steps from before, you can send yourself an attachment... only this time you send yourself what's on the GAMEPAD screen: the zoomed part. That zoom ALONE is as big as a normal sharing on Miiverse: around 800 x 450.
4. Send yourself the zoomed images of the artwork. I had 9 that have a black border; yes that's a real drag.
5. Assembly is required in a photo editor program. That's another drag.
6. Once assembled and properly edited, your artwork will be around 1800 x 1000 px; or 25 x 14 INCHES, as I suspected. The resolution is BEASTLY and can easily be printed as a great poster.
Don't believe the crazy Hipster? Here's some PROOF! with my own artwork.
Also, here's the thing: The red rectangle represents the zoomed area when working in Art Academy; it also represents the exported size in Miiverse. The rest is the real size of the artwork.
I just though I'd share this with you people. These type of things get heavily on my nerves and I'm glad there's a way to get all those juicy details and textures Miiverse artists work so hard to do, and rightfully deserve... Or at least if you are as obsessively compulsive as I am. Chances are, you won't even like having the artwork so big.
(I've put up a little grid, in case someone wants it, it should help if you're interested in pre-sketching and arranging stuff for Art Academy.)