I don't know if you could have but I think it's safe to assume that if you had invested the same amount of time in learning to pixel straight then in the two days you could have made something that not only is as pleasing to look at (because it is pleasing to look at, of course) but would also have about it the air of control and intentionality that pushed-the-single-pixels work carries.
If it takes you 3 hours to do that portrait though you are a competent artist otherwise, there must be a problem in your tool chain or your methodology as a pixel artist and that is what Pixelation is here to help you with. The Low Spec Art section is not here for things that counter the ethos that Pixelation stands for: intentionality, control, working around limitations smartly. It's not here so people can post cgi-color-reduced stuff that look like pixel art and then say I saved this amount of time not doing my pixel art properly.
I don't mean to make this into a big thing, but if Low Spec Art creates a different sort of culture to Pixelation's main one, especially one that runs counter to what Pixelation is about, then it needs to go. There's been way too many asspats and 'make a game using that model, it'll be awesome!!
' posts and not enough critique and this is already a wound in this subforum's side. Actually starting posting cgi-drawn-color-reduced-downscaled-almost-pixel-art is quite another. I like looking at the pretty art as much as anybody, especially the 3d pieces, but if the same modus operandi of Pixelation with critique and betterment doesn't occur, then what use this subforum is should be reconsidered.
