This post concentrates on brushes used around the lashline area; the eyeliner and mascara brushes.
I love eyeliner and I am meticulous about eyeliner. How am I meticulous? I love doing the fine and detailed natural looking liner stuff. You might think that is no fun. Well, it is harder to do the fine-line look than the big smudged line look which I like also. Learn the way of fine lining and the rest will easily come together. (Sounds like a makeup zen moment doesn't it?)
Anyway, these are the brushes that I have out all the time for eyelining, smudging, and mascara application.
The two brushes above are my go-to eyeliner brushes. The Brush Up Kolinsky Sable Liner brush ($6.76USD). This is the one on the left. It makes a thin line that gives definition to the lashline and a very thin (fine) winged line if needed. This one is more for the natural look. I use this for the bottom lashline if I want it defined without making my eyes look small. Cinema Secrets Filbert Kolinsky #2 ($11.49USD) is my other eyeliner brush that I pretty much use for a thicker line that is much more visible. I also use it for just about any other eyeliner look like a winged out look in the third picture. It is the type of brush that is firm enough to grab enough color on the tip whether it be a liquid, gel, powder, or cream and to spread evenly onto the lashline without skipping.
Smudge brushes are what I use to blend my liner into a soft line. The size of the smudger determines the spread of the blend for me. Paula Dorf smudge brush ($20USD) is the brush I use to soften an eyeline just enough to diffuse it. The hair is, I believe squirrel if I haven't mentioned it before or maybe goat, I just don't remember. It is a soft hair which results in just a soft smudge. It will leave the defined liner in place while smudging it just a bit. The Becca Eye smudge brush #37 ($25SD) is more firm and stiff since it is sable hair. This one will smudge out a line for a smoky eye look for small lids. It pretty much diffuses the eyeliner. So, if you want that extra smudged liner look, this is the one to use.
I have no particular name brand for this one because I got it on sale at an art supply store for like $2USD. The hair is a stiff type and works well with mascara and for my stiff lashes. I have tried the soft taklon (yellow and orange synthetic) ones but they just didn't do much for application of thick goopy mascara, pretty much good for the thin coating cake mascaras. The original shape of the brush was a complete fan but I trimmed it to suit my needs. If you buy one, just don't cut across it; snip into it like you do when cutting bangs. You know, vertically cut into it. I also cut the sides because they just get in the way and pretty much unnecessary for mascara application. The picture shows me coating my lashes with white mascara (making it easier to see the results). It gets down to the root of the lashes, lifting the lashes upward. This method isn't for everyone and can be tedious. I have been doing it for ages and find it no different in taking time than regular mascara application.
Those are the brushes I have out all the time for eyelining and mascara. Nothing exciting but a useful bunch.