Okay, one critique coming right up.First impressions: I like. Calmness. Bit dark. Sad. Overcast, slightly heavy (as in, heavy hearted).Those were the emotions that first jumped to my mind. Do they match what you tried to convey?Okay, onto the technical aspects.First, the lighting and colouring.I like the way you did your buildings. It's something I struggle with and what I feel is that the way you did here seems like a very good compromise between having visually interesting buildings (mostly, because they have several shades rather than just "bright" and "dark") but not too intricate as to require a too much time. The benefit of this flatter coloring is that the buildings don't quite pull my eyes as much. Same goes for the plants.In short, I like how you both have been able to add in a lot of detail without it calling too much attention to itself while also, I'm guessing, not requiring too much time.That said, if the buildings/plants don't wrongfully grab my attention, I don't feel like Celestia really grabs my attention either. If you look at her rear, her coat colour is very close to the mesh door behind her. While we can still tell where she begins and ends, there's very little contrast there.Instead, given the light source, it perhaps would have been appropriate to give her a slightly brighter outline. Not too much, because I am guessing that you deliberately wanted a more "muted" colour palette in this drawing rather than bright vivid colours, but I think that just a little more would help her and also draw our eyes towards her. A bit like what you did with the right edge of her front right leg.Speaking of muted colours, I do like how you drew Celestia's mane. The highlights are made using the actual pastel colour rather than white, which again gives that sense of shine, but a very subdued one. That being said, on her tail, I think the right side could use with a bit less brightness. It's supposed to be behind Celestia relative to the light source. Also, it also doesn't quite fit in with the rest of the tail's dark colours. Some bright colours there as an accent is good to give it shape and depth, but this feels like a bit too much.Finally, I like the way that one line of bright yellow conveys the feeling of "gold" on Celestia's collar. I find that the lighting doesn't really make sense (what's bright that's bouncing light off it?), but I think that for the sake of conveying the sense of gold, it's acceptable. Or, on second thought, maybe placing it at the back of her neck, a highlight of yellow there would help both make the lighting seem more real while also conveying that golden sheen, the same way we did with her flank.Second: Perspective, composition and posesI like the circular composition.But maybe placing Twilight closer to the centre of its would have helped. I say this because like with Celestia, her colours are very muted and she doesn't stand out much from the background sky. I presume, once again, that the muted colours are deliberate to convey that sense of distance and "goneness" of her dear pupil.So if we don't want to add any bright sheens on Twilight, changing her position to be just slightly more to the left may help draw our eyes towards her.For Celestia, I find her pose just slightly off. Mostly, it's the positioning of her legs. I don't know how to say it, they don't feel natural. I think that she is supposed to have stopped mid-step to see Twilight take off but the way her legs are positioned, it doesn't feel like she was in the middle of walking cycle. Her rear two legs are also very straight and headed in parallel, almost like her rear two whooves are tied together.Third: Things I forgot to mentionI realy like the shading of your clouds. It conveys that sense of a "tunnel" very well, again, giving us that sense of "leaving" and "goneness." But there are parts where I feel that I can clearly see where you went over once, then again in a partial overlap with the brush tool. It's especially noticeable on the right side of the "hole" in the sky, where it doesn't feel like clouds as much as "Ah yes, the artist made small bumps with the brush tool to make clouds." Not terrible, but it's a bit like when the special effects in a movie feel like special effects rather than what they're actually portraying.Oh, and I also love the stone path. Goodness me I love the way you did that. I never, ever know how to draw stone paths or anything on the ground really without it coming out awful.Fourth: Questions and comments.I actually really like the way your colours in the background elements like the plants or the buildings don't blend. Maybe a bit more in the clouds to help with that previously mentioned "feels like a tool" problem may help, but for the buildings and other elements, I really like the look. The tree branches above Celestia being just green rather than brown is interesting too me. Trying to convey just that sense that there's a tree there without necessarily going for "realism" so to speak. I also like how there's a very "blobby" feel ot the leafs. Just circles floating in the air. Again, not realistic, but itI bring up the non-blending colours because I notice that Celestia doesn't seem to be painted quite the same way. Her wings also have that "non-blended" colour look, but the rest of her coat feels very graded in shading. Did you want her coat to be more smooth on purpose so she would feel visually distinct from the rest of the drawing? Also, did you use a brush that blends colours a bit more there or did you use the same non-blending tool, but using many, many more intermediate shades?Closing thoughtsSo I brought up a lot of tidbits, but honestly, those are just small details.Truth is, I think I'm going to learn far more from this drawing than you are going to learn from my critique.Keep it up.