Elsa/Anna Behind the Scenes

   First thing to do on any animation is block everything out. Get the characters in position, set keyframes, turn on auto-keyframes, and get to work.   

   I select every bone in the rig (save for deform bones) and add location/rotation/scale keyframes. I primarily use the main torso bones, IK, and the adjustment widgets, but you never know when you need some fine movement, and there's nothing worse than setting a pose perfectly only to have it snap back when you step forward a frame. Believe me, I've had it happen many times (most recent being... yesterday). So I just set a damn keyframe on everything, whether or not I end up using it. 

   I've been basically forgoing storyboards and setting things up with cameras in Blender after the basic blockout is done (just the main poses). I have a general process of action in mind, but I might spend a couple days messing around with the timing/angles. This process is similar to a “pre-vis.” I use to do boards but I ended up changing so much and spending so much time in this process anyway, that I figured I'd just cut out that step. I focus on this part so much because once it's all locked in time wise, there's really no changing it. You might think of a “better” idea down the line, but implementing it would require adjusting all of the frames and constraints, which always leads to some form of confusion. So I want to be pretty happy with the timing before blocking out animations; an important thing to remember, of course, is that “done is better than perfect.” We could easily work on these damn things forever, right? 

   Instead of animating one camera jumping around I use a new camera for virtually every shot, even when it's intended to cut back and forth. This gives me room for experimentation (though the viewport quickly gets messy if you don't take steps to place everything properly in collections).   

   You'll notice lots of “cheating” going on there, I.E. Elsa doesn't really “walk” up to Anna, her body is dragged by her feet, which are the only thing the camera sees. It's obviously wasted time to animate something not seen by the viewer (another reason to have all the cameras set up first), but as an aside I do intend to implement more walking/moving in the future. It's something I feel is under-utilized in this type of work, partially because we don't walk when we fuck, of course, but also because it's a challenge to do well. I'm visualizing someone walking around a bound sub running her finger along her, but I digress.   

   When visualizing this animation, I figured it would all go off without a hitch. It's really not the most complicated thing conceptually, so I'd be able to focus on the timing and sensuality.   

   Not so! I didn't foresee two challenges and they both ended up taking over a day to figure out; having Elsa's hand turn the crank and having Elsa run her finger along Anna's face.   

   My initial idea with the crank was to place the pivot of the crank object at the rotation center, and then animate that 720 degrees, parenting Elsa's hand to the crank. This almost worked, but Elsa's hand ended up “breaking,” the wrist joint rotating around with the crank. 

   I tried a few things, including parenting both the hand and the crank to a curve, and using a child-of constraint combined with a track-to constraint to keep the hand set forward (still not totally sure why that didn't work. Heh).   

   In the end I simply animated the crank and used a child-of constraint on the hand set to a curve object, syncing them up to the best of my ability. I'm not totally satisfied with the result, but it looked decent on camera, so I moved on! Definitely something to delve into more at a later date.   

   For Elsa running her hand down Anna's face, you have something that is always tricky: fine touching and interactions between two characters. I animated Anna's head first, so that I would have a reference for Elsa hands. The issue came in keyframe interpolation; setting two keyframes, one high, one low, would lead to an intersection on the forehead. I could add supplemental keyframes to remove this, but then the motion looked jerky (wanted it to be very smooth). 

  
 I experimented again with constraints, taking some vertices out of Anna's face and making a curve out of it, to parent Elsa's hand to. It still looked a bit jerky, and as anyone whose used Blender knows, animating on/off child-of constraints often leads to the object jumping a bit (hoping this is something that's improved).     

   I ended up delving into the graph editor a bit, modifying the handles and interpolation type (high=bezier, low=linear). This is something I want to do more and more of; my goal is to master the graph editor. It's truly a unique beast and I haven't been taking advantage of it as much as I could be.   

  You may notice they don't have eyes in some of these gifs. Spooky. You have to disable as much as you can in the Blender viewport to be able to animate at 24fps. If/when Blender is optimized for better animation playback, I wouldn't mind making the jump to 60fps animations. This is one area where Maya wins, heh. 

   Hope this has been illuminating/helpful! I like giving advice and helping people out, so always feel free to ask questions on here or on my Discord.  

   Will have a new Foot Fetish video going up soon (likely by Saturday if I get the voice work by then; Lady Lustria will be doing it!) I've got the script done for the 2B tickle animation, and I think it's gonna be a doozy. The machine will be escalating the experience throughout the movie, so expect quite the climax.   

   Have a good one!