I'd love to get advice, I'm really planning to push my skills as hard as possible these coming months. I just painted this stone wall texture for use in a well, it seems to tile relatively well but it seems incredibly flat and dull, not entirely sure what else I can add to it. Any and all constructive criticism is totally welcome, I wanna improve as much as possible. I painted it in 1024x1024 so I feel there's alot of potential to add in some great details if I can figure out how:

I also noticed there are some tiling artifacts/seams, I'll get rid of those in the next improved version after some good advice.

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https://www.youtube.com/watch?v=c_GWVez_UHM
https://www.youtube.com/watch?v=QSFKEvH6ZJA
If you watch those two workshops and absorb all the information, you'll be on your way quite nicely.
I agree with sipher, what you have here is a great start, just push the highlights and shadows further, some moderate jagged texture, slightly discolor some stones, darken some as if they were pushed further in (works best with smaller ones). Don't be afraid of harder brushes with stone.
The links above cover stone
wow thanks for the links man
Anyway, here's what I've got so far, I'm pretty happy with it, but I'll take any suggestions:
I'll be back with some improvements. XD
I learned SO MUCH from that paintover.
I still feel like I have just scratched the tip of the iceberg on improving this. I definitely need to get over my fear of making things stand out too much, because at the expense of slightly more noticeable tiling, I've already been able to define a much stronger style. It just occurred to me that there are a handful of stones that still look really flat and blurry but I'll probably get back to this tomorrow morning, for now I need to try this cool thing I heard of, I think it's called sleep or something.
Always keep in mind where your light is coming from. I always paint my highlights/shadows as if the light was coming from the upper left.
I only figured this out a couple weeks ago, but to overcome the noticeable tiling thing, make the some of those stand-out details cross over the invisible seams. Say for instance you notice the green stones make a grid-like effect when tiling, place them more randomly and make some cross over the edge seams.
Yes sleep! And food. Give your mind the ammo to make good art. Keep it up!
Unless of coarse anyone notices more potential improvements to be made.
You're doing great!
But I think the texture is too blurry and there are to many pixel artifacts.
I think the soft subdued texture you've made may work in some games depending on the art direction, but I agree with the others, it would benefit from some harder edges.
Anyway, looking very nice!
I tried to make some harder edges and darker cracks, and I desaturated it just a little, but pushed some of the highlights. I'll probably revisit this texture after I make a few more once my skills have gotten considerably better.
Here's a texture I just started, it's going to be used on relatively old and worn wooden beams. The texture tiles in all directions and will be wrapped around a blocky beam of wood, which explains the four large creases. I know it looks horrible now but I wanted to upload a reference so I can make some progress and look back on how it changed. Anyway, I'll be back after carving this thing out and adding some color variation.
Here is a .gif from another thread from a colleague of mine, Royalshark, that she did to present her processes.
Parrot on the Polycount forums also has some great hand painted process tutorials up on youtube. I believe his full name is Jeff Parrot. Hes got some great examples on his portfolio, and he is a really nice guy if you want to ask him any questions (PMed him in the past).
Dont rush through the process to get to the finish line. Get your bases down and then start layering on top, and keep layering and adjusting until you have your desired results. Keep it up though man, the fact that you are looking for feedback in the first place is a great first step to becoming an even better artist.
I didn't paint over a photo, I'm trying to learn to do this all from scratch so I just sketched in some quick details to get an idea of the direction I'm wanting to head in.
Thanks for recommending Jeff Parrot, he has some great reference material.
I started over from scratch this time, and I think the colors balance well in this one. I tried to push the brush strokes, the darks and the lights, the bevels, without using low opacity soft brushes. Instead I just sampled and used hard brushes.
Here's what I got so far, keep in mind this is really heavy wip:
I'd love some feedback, especially on the concrete.
Keep in mind that I'm trying to keep these textures smooth, this well is well is several years old and it's in the center of the village, so I imagine people would be rubbing their greasy hands all over it, eventually smoothing it. I think the same would go for the concrete, but right now it reads more like butter. XD
I need to find a way to make the concrete rougher, while still maintaining a smooth appearance. Any advice on solving this paradox? XD
Also don't worry, I'll eventually fill in all of that empty texture space with various plants and junk.
The wood texture definitely looks better, though it still is too soft for my tastes. Bring up the contrast a bit on the texture and define the planks a bit more. All in all you are making great progress!
I agree that your grass is too small and is kind of looking jpeg artifacty. One of the things you might consider doing is making a big kit of all different types of carvings and details added to your wood so it's not just "slab of wood....slab of wood."
As for your rock texture, I think you might want to watch out for the "braining" of some of your rocks, as in, they kind of look like brains :P. It might just be the swirliness mixed with the colour, but watch out for that, as it's sort of oddly organic inside of the rock. I'd add some really sharp cracks to really sell that.
Do you plan on making spec and normals for these guys? if not I'd add a lot more lighting definition into your materials to make them look more 3D.
Overall, looking really good!
You can still push the detail and sharp darks in the wood texture, similar to the level of detail in that knot near the upper right corner.
I'm having a ton of trouble with this next texture. I just started it but I can't figure out where to go with it:
I know I should totally redo it, but where should I start? The textures I've done before were very round and organic, but I'm wanting this cliff texture to be incredibly blocky and geometric, so I'm sure I'm starting off on the wrong foot. I want the final texture to resemble something like this:
Any advice?