In this tutorial we will cover some of the methods I use to model a hand. A lot of the knowledge you need to do this is anatomy and observation. I'll cover some of the tools I use and more importantly the patterns I implement.
Writing a tutorial for something like modeling a hand is a difficult thing. It's something very dependant on the type of hand you want to make. Young, old, male, female, high poly, low poly, in pose, for rigging, etc and on and on. It really depends on what you want it to look like and what you want it to do. What I can provide you with are general patterns of geometry that usually give you a foundation to keep carving more and more geometry on and end up with what ever model you like.
When it comes to characters, or any other complex things that I know I will have to model over and over, I will sit down and spend time developing these patterns. Patterns that if I start with, as I go on the amount of work I have to do, such as trying to figure out how to cut in a shape has become limited. If I can develop some sort of work flow, the production becomes easier and quicker, which is always one of your goals in production. This tutorial is merely a suggestion. By no means what I am about to show a rule of any kind. No two hands I've ever built use the exact same patterns of geometry. I just start out in one place with my patterns I've developed, but each model takes me to a different result depending on its look and function. These patterns work in some extent from low poly up into high poly models. Where you stop depends how many of them you use and again what you're needs are of the model. Don't hesitate to try your own methods when it comes to your own models.
The tools I use here in Maya are May's Split Polygon tool, Maya's Split Edge Ring tool, Extrude Face, MJ Poly Tools, APE Split, NEX and Active smooth. Of course there will be a few other features I use here and there as well. All these tools I have set up to hot keys so I can access them quickly and easily, because I'll be using them frequently. Personally I find it extremely frustrating and time consuming to try and sculpt without these tools set to hot keys any more.
So here's the premise I'm working on. There are three stages of working up to high poly. Volume, Surface and then detail. First we'll block out the underlying structure of the model low poly. This is where those underlying patterns become important as they will guide the rest of the geometry to start to cut it. After you've taken care of that it's onto smoothing out the surface. Defining the surface as you want it. Not quite things like wrinkles but generally the over all shape of everything. After you've gotten that into place we add the finishing details. Wrinkles, seems, finger nails, eye lashes, etc. The reasoning here is you're looking to have to move geometry around as little as possible. If things are mostly in the right place as you're cutting in new geometry, it's much less movement to place those new verts. Moving around large masses of geometry it time consuming to even and smooth out. So we're going to try to avoid it in the first place.
A note before we actually start modeling. I really don't ever using image planes to rotoscope when it comes to hands. It just never works out well trying to get things like fingers to line up and the perspective to match. You already have the best reference you can get and they're probably on the mouse and key board right now. Take a good look at your own hands from every angle possible while doing this tutorial. Ideally we want a nice relaxed posed, which will be most suitable for rigging later. Nothing flexed and nothing clenched. If you've heavily relied on templates up to now it's time to let go a little and become an actual sculptor rather than a tracer.
You can download the model of the hand here.
So let's start this thing off by making a cube. We'll subdivide its width 3 times and it's length once so we have something that looks like this.
The four faces on the front will later be where the fingers come out of the face on the side, on the opposite side from the fingers will be where we extrude out the thumb. The single sub division across the center of the length will be where the knuckles of the palm are. Let's slide that up closer to the fingers and the space below that will be the palm of the hand.
Select one of the faces on the side of them palm to extrude out the thumb. We'll angle this a little so we can easily extrude out the thumb at a little more natural angle.
Here is the shape we're trying to mimic if you're still unclear.
To give ourselves a little more room we'll start to extrude out the first segment of fingers. So that all the fingers aren't extruded as one piece, we're going to bevel the edges between each finger first. Select the three edges in the front of the palm. And bevel them a little.
The actual settings you use may depend on your scale. So if it's too much or too little, just undo, adjust the number and try again.
We'll select the four faces for each finger now and extrude them out a length.
If the tool looks a little odd to you it's because I'm using NEX and you probably aren't. The green face is the auto highlight. When using NEX I can easily extrude faces by hold CTRL+ Shift and MMD. Again just how a little short cut can save me the time of digging through menus.
Next, we'll do the same thing for the thumb.
Now is as good a time as any. I'm going to edge loop split the height of the whole model. I use MJ Poly Tools to do this. Again I have a hot key set up so I simply select and edge and hit a couple buttons on the keyboard.
We will extrude out the thumb a little bit more before the next step.
Ok, so while this so far is defiantly a pattern I'd say makes things easier In the long run it's pretty simple and anybody could pretty much figure this much out. One part of most modeled hands that I usually see is lacking is the webbing between the index finger and the thumb. Take a moment to observe your own hand and move your thumb around and notice how the skin there moves. When it comes to rigging an area like this it's very difficult. The skin here almost moves more like cloth since there's little underneath that area to hold its shape and just the amount it stretches and moves compared to other parts of the body. The best you can do is find the average of the range of movement and try to sculpt that.
So the first step I've found to best model this area is to delete the two faces in the crook of the thumb. The two that run up the side of the index fingers, right by the knuckles of the palm.
In my observation of the hand and models of hands I've observe that look wrong to me the error seemed to have been in modeling the thumb straight out to the side, In reality if you're modeling a relaxed pose the thumb seems to come down at about a 45 degree angle. The webbing between the thumb and index seems to travel up and twist from say pointing up to pointing sideways. So we're going to make our geometry start doing the same thing. Using the middle edge of the thumb I'll point snap that vert to the knuckles. Holding V is the hot key for point snap. Hold it down for it to be on. It turns back off on release.
Next I'll cut in a new edge from the lower corner of that last thumb face to the center of the edge across from it.
And then with that new edge point snap it to the middle of the index finger.
We have one point left to fill the hole. I'm going to add a point by doing a single cut to that last triangle on the thumb, then point snap it to fill the hole up.
Now you may have noticed this already, but now is a good enough time to point this out. Everything we're modeling is in quads. Meaning that each face has four sides. No triangles and no five sided faces are really here yet (except the bevels we made earlier, but they aren't done.) Why is this? Well, when making high poly models, good change you're going to smooth the geometry later. Quads are going to give you the best results for this. Best results meaning that'll keep your geometry patterns as much as possible. As a guide we try to keep all faces quads, and we try to avoid anything more than 5 pointed stars. Stars are what I reefer to as 5 or more edges come out from a single vert. Much more than that and when you smooth you'll have ever more verts coming from that point. If that area of the model is one that has to deform a lot, a good change that area will create a dimple weather wanted or not.
I say guide here because there's always exceptions. There are certain patterns where 3 and 5 sided face will end up as quads when smoothed, or you may want an area to dimple in motion. The choice is simple guided by the understanding of the results of cutting a certain way. But for now, most of the time quads are you goal.
While we filled up the hole it's still there. Like sheet metal fitted together it won't stick unless it's welded. So we should weld our verts together. Easiest way to do this is select that whole mass (don't worry if you have more verts than what you moved. Just grab that whole area) and lets go to the weld options.
We're going to set the options to a really low distance. That way only verts that are super close together will be welded to each other.
Once again, this is a tool I use often and have a hot key set up for both the menu and the tool as well.
Back to observing our own hands. Again when observing poor models of hands one feature I've seen is the neglect to the opposable thumb. They've modeled the thumb facing down just like the rest of the fingers. On my own hand, no matter how much I flex it I can't get it to the same angle as the rest of my fingers. In a relaxed pose my thumb is turned nearly 90 degrees to the rest of my fingers. So I'm going to twist the geometry on my thumb roughly 90 degrees to reflect that.
You can see how the underside of the palm now turns to face sideways.
Back to the fingers. We'll extrude out the next section of knuckle.
If you hold out your hand flat and look at it from the wide you'll see your hand's over all shape is a wedge. So we'll start to reflect that some by scaling down the fingers a little.
As well as wedging the hand out, I'm also going to start to round out the fingers some. Notice the curvature over the palm as well.
Another thing I see a lot of people miss is the space between the fingers. A lot of people leave the geometry there straight up and down like we currently have it. Well, it wedges backwards as well. I'm going to pull the geometry back there and begin to angle it.
Here I am just blocking out more of the overall shape. I want some of the wrist in here as well. When I make hands for a character I usually build them separate and then weld the hand onto the arm I've already made. Having a bit of wrist just helps with the transition and getting the proportions right.
To finish most of the volume work we're going to extrude out the rest of the fingers. One extrusion per a segment of finger and one extrusion per a knuckle.
At this point I'll spend a little time shaping this hand into its relaxed shape some. Notice I'm not extremely precise here. There's no point in wasting time micromanaging this geometry with all the new parts we still need to carve in.
So next to round these fingers out a little more, I'm going to make and edge loop split up each of the fingers. This would be a case where I might use APE split to make things a little rounder without having to move verts myself.
Moving our attention back to the webbing of the hand, we're going to go back between the thumb and index figure and extrude out a number of the faces there for the start of the webbing. I'll try my best to display which faces I choose in this image.
Extrude and scale in those faces.
Just to make sure I'm not the right track I'm going to use Active Smooth to take a quick glimpse of how my model looks smoothed. Usually when I model high poly my models will be smoothed at some point so it's important that I'm looking at the results of a smooth all the time to make sure I'm not building in features that don't smooth well.
The pattern wrapping around the thumb is a little tricky. What the loops end up doing are they come across the palm of the hand, around the top side of the hand, back around the thumb and then the edges travel up and over the fingers. Here I'm starting to cut edges around the thumb to move up the fingers. Rather than the edges traveling down the palm to the wrist, they'll travel down and around the thumb. At least till about the middle finger they will any way.
Here's a selection starting to show how the edges will wrap around this hand.
Since the edges don't need to travel down the fingers and across the palms, I'm going to delete the old edges to they now travel down around the thumb.
This may be a little difficult to follow at this point because I'm working all the way around the hand. What I'm doing here is simply cutting edge loops around the hand as I described before. Some times I may redirect edges that are already there for spacing sake.
Here I've decided to take one of the loops around across the webbing of the thumb. Remember, this isn't an exact science. This is a general pattern I follow. But every time I model a hand I'm still trying to figure out where to place these new edges I'm cutting.
Here I'm taking the edges going down the thumb and they will travel across the palm, around the back side of the hand, back around the thumb and up and over the fingers.
On this particular model I've diced I need some more geometry in that space between the finger and the thumb that I have selected so I'm going to edge loop split it. Part of getting a smooth model that deforms well is trying to get your faces a generally uniformed size. Meaning that I usually try to get the faces roughly the same size for a given area. Again, this is just a guide and not a rule.
To get rid of that new triangle it created in that space, I'm going to collapse an edge. The one I collapse is the one between the triangle and the five sided polygon.
I feel the edges going down the thumb part of the palm are too wide still. Again, we're looking for more square shaped faces if you don't want to see ripples in our geometry when we smooth. So I'm going to cut in a new edge here.
Here I'm cutting and redirecting the edges from around the thumb and up the fingers. The edges coming down the thumb going across the palm.
So stepping back and look at what we have so far we can start to see what we need to do still.
Honestly, this is still rubbish to my standards. Maybe not so bad for something low poly, but it lacks detail in form. Even if we didn't cut in any more geometry we could mange the geometry better. So we've still got some work to do here. The fingers are still pretty blocky at this point so I'm going to go turn my attention back to them.
I've decided after looking at my own hand that the webbing up the index finger goes too far. My hand it doesn't really go past the first knuckle, so I'm going to pull it back a little, as well add a couple edge loops for that segment of finger.
A note on rigging joints. The guide for making joints that will deform well are you need three edges. Three edges will define a single curve. And three edges will hold a shape through deformation. At the knuckle, with three loops to define it we have two faces on the inside of those edges and then the faces outside of them. So say we're looking at your knuckle and we draw a line right down the center of it and a little to each side of it. As you bend your finger the edges on the outside hold and keep the shape of the segments of your fingers. The faces between those edges deform and bend while the faces outside don't really. I'm just kind of breezing over this since this isn't a rigging tutorial, but when ever you are rigging for animation it's important to understand these concepts so you build a functioning machine rather than just some pretty art work that can't move.
So I'm going to start cutting in these edges. Note we're cutting in an edge on each segment of finger as well. Not for rigging, but so we can define their curvature.
Ok. So we've cut in all this geometry. These are the underlying patterns that are going to give us the building blocks we need to sculpt the shape we're looking for. So, time to start sculpting. To do this I'm going to display the wireframe for the model and use softmod to space out edges and shape things. If you delete history of the model the softmod nodes shouldn't stay on the model. If they do, just hide deformers in your view and you can delete history later.
Adjust the fall off to a reasonable size to move a small chuck of geometry at a time and start spacing out your faces to a more uniform size, as well as shaping the hand.
You may find that your softmod fall off jumps all over the place in size every time you make a new selection. I've found Softmod really only likes to work well if you have your preferences set to use centimeters. Anything smaller or larger and it changes size all the time.
So here's a demonstration of the theory behind why we've been cutting the geometry the way we have. The red lines follow the creases of the hand. Our geometry is mimicking that pattern. As you space out the geometry on the palm try to match these patterns. Again, your own hand is a great example for this.
So next I'm going to make some bigger motions in sculpting by using the paint sculpt tool. I'm going to show you where the menus are for these tools but as I keep saying I have hot keys set up for all of these, so I never have to dig through these menus.
I started of by smoothing the model. Low poly models tend to be a little harder to control than a high poly model. So the plan is to smooth the model (so don't delete the history after this step for now) sculpt it, then unsmooth it. Smoothing is also gives us a better idea of the final product as well.
I'm going to use the paint sculpt tool now to smooth the geometry out a bit more and resculpt the model some.
So some notes on the sculpt tool. Holing down u allows you to left click and bring up a marking menu to choose whether you want to pull push or smooth out your model. Right now we're going to smooth it out. Holding down b and left click dragging lets you change the brush size. Holding down m and left click dragging lets you change the magnitude of the displacement. Now when it comes to smoothing you want to be reserved. Smoothing averages out the verts of the whole model. What happens when you completely average all the verts of a model? They implode. So we want just enough to take some of the work out of the spacing for us.
Often after smoothing you have to resculpt a bit to get some of the volume back.
So after we've smoothed things out a little, we'll put some of the volume back. To do this we're going to hide the wire frame so we can see what we're doing.
You'll notice that as soon as you start back up the sculpt tool you're wire frame is back.
You'll want to turn it off in your sculpt tool settings down at the bottom. This is often what I have my sculpt tool set to.
Here I've sculpted the palm back in some. Yes it's lumpy and not perfect, but it gets the over all volume pretty close. At this point I'm going to unsmooth the model and go back to modeling low poly.
In the channel box I'm going to look for the smooth node ad select it. In there I'll turn the divisions back down to zero. I can delete history now again after this point if I want.
And here's what you're left with. You can see the lumpiness we had before doesn't really show any more.
So I'm going to go back to the fingers now and extrude out a little more geometry for the knuckles. Here we're doing the same thing we did for the webbing of the hand earlier and just scaling down the extrusion.
Next I'll cut a few more edges across the fingers to be able to define the shape better. Like I said before, I like to use at least three edges to define a curve.
From here it's really just spending some time and sculpting the geometry we already have in place. Examine your own hand and just look at your model from every angle possible and examine its features, and try to incorporate what you see on yourself.
You may find it difficult to work on the middle and ring finger just because it's surrounded by other geometry. Flying inside the model can be helpful at times to deal with that. But don't forget it's the outside that matters.
The last cut I'll make for now is I'm going to curve out and pull back the webbing between each finger a little.
From this point on I'm adjusting the shape of everything and making sure my proportions are all right. Observing things like where the knuckle of the thumb lines up with other knuckles. Where the tip of the thumb lines up with the rest of the hand. Observing where one part lines up with another is how you model without templates. It takes time and practice to get good at it. The more hands you make the better you'll be. You're first had won't be that great. Just accept it and make another one. And then another one and another one, and just try to make each one better than the last. Repetition is a great teacher for speed and quality so sometimes building as many as you can as quick as you can can teach you much more than spending a ton of time on a single model trying to get it right in the first shot. The short lesson is that learning by failure can often be a much better teacher than only learning by success. Spot your mistakes from your first attempt and then start all over trying to avoid them the second time around.
Here's what I've ended up with after spending a bit of time shaping this. I've adjusted a bit of the proportions too just from observations of my own hand. The palm needed to be a little longer, the base of the thumb pulled back some. I haven't added finger nails in this case, but I'm sure you can figure out multiple ways to add them. This is smoothed, and if I was leaving it smoothed, I'd sculpt it more even here. There are lots of directions you could go from here or you could call this a finished product. It really just depends on your needs.
Here are some examples of a couple other hands I've made before. I used the same method to model these but you can see how the geometry is a little different. It's the same concept though and that's what really matters. That these fundamental ideas can take you different directions in the end, and by utilizing these patterns you can have a fairly quick turn around time on something fairly detailed and ready to rig.
You can download the model of the hand here.