Sculpting & Painting a Realistic Human Eyeball with ZBrush

from an anatomical perspective an  eyeball consists of many different parts but in 3d we usually wrap it  in two or three separate layers the main layers are iris, sclera and cornea Iris is the ring-shaped area  which defines the eye color Sclera is the white outer layer of the eyeball Cornea is the transparent front part of  the eye that covers the iris and pupil I usually combine the iris and the sclera in one   single geometry and add another  transparent top for the cornea but some artists separate the  iris and the sclera as well so to begin draw a sphere into the canvas and  then go to the edit mode by pressing the T key now you have to click on "Make  PolyMesh3D" in the tool menu change the material to basic after that rotate the sphere 90 degrees around the  x-axis so that the cap points towards the canvas now duplicate the current sub-tool the second sub-tool will be used for the cornea   but we don't need it right  now so you can just hide it change the brush stroke to DragRect with the right intensity bow the surface in  so it gives you the basic form of the iris keep the size about the  half of the eyeball's radius now we can cut the pupil out while holding the Ctrl key change the stroke  mode to Lasso and select the first two rings change the display mode to Double and exclude any   other polys that you might  have accidentally selected go to the Geometry menu and in  the "Modify Topology" submenu   click on Delete Hidden to cut the  polygons that we just masked out subdivide the mesh a few times so that you have  enough topology to play with for the details in the Transform menu click on "Activate  Symmetry" and also turn on the radial mode   then change the radial count to 12. you can see that the symmetry is around the  wrong axis and we have to change the axis to z pick the Dam Standard brush and in the Stroke menu   crank up the "Mouse Average" to max and  also increase the "Roll Distance" to 5. start with drawing straight lines  then add more curves and details for this step use as many references as you can try different sizes and intensities for the brush  and also avoid drawing too many parallel lines our goal is to make it look as organic as possible now for the ciliary muscles while holding  the Ctrl key first draw the pattern as a mask start with drawing sharp edges and then  use soft strokes to smooth the outer areas turn off the symmetry and add a few  unique strokes and patterns to each side after you're done with the pattern go to  the Masking menu and click on "Inverse" you can use either the Standard or the  Inflat brush to bump up the geometry use the highest intensity for the  middle and go easier towards the edges after you're happy with the  result you can clear the mask now it's time to finish and clean up the edge you can see that after popping out the geometry  there are many jagged edges which need to be clean the more time you spend on this  forms the cleaner the result will be while having the radial symmetry  on use the Standard brush to add   a little bump to the outer edge of the iris in order to paint with the Standard brush turn  off Zadd on the top toolbar and turn on RGB pick up any color and stroke once on the surface now ZBrush knows that you're in painting mode enter this RGB code for this clear and  hit "Fill Object" in the color menu to start painting the iris you can either copy   my codes or enter the RGB codes that  you wrote down from a reference photo be careful not to make a sharp line for the edge if you look at some references you can see   that the edge between iris and  sclera is rather soft and blurry the color of the iris normally becomes a little  bit darker towards the center and the edge now to add more details I'm trying  to add highlights using different   brush sizes with brighter and more vivid colors to paint the blood veins and vessels,   I use high-contrast lightening  images as alphas for the brush but before that first I add  a blood gradient throughout   the surface of this clear to  have it as background color also adding some orange color variant in spray  mode helps to make it look more realistic while still in spray mode, I choose  a lightning image for the alpha to   add vessels all over the surface in low intensity you can also turn on Zadd as well as RGB to add a   little bump to the surface  while painting the vessels I pick another lightning variation for the  alpha to make the vessels look more diverse now I change the brush mode to drag rec  to add more prominent vessels individually you can see that the vessel looks  a bit too sharp so in alpha menu   I increase the blur intensity to 10. if you remember we duplicated  a subtool for the cornea now the only thing we need to do here is add a   bump to the center of the cap  at the same size as the iris also in the Size submenu I increased the scale  just a bit so that it covers the layer beneath finally if you'd like to render  the object in any other software   you can just export the maps  using "Multi-Map Exporter" thank you for watching the video if you have any questions just  let me know in the comments. until next time!

Channel: Hadi Karimi

Views: 16,762

Rating: 4.9963503 out of 5

Keywords: Pixologic, ZBrush, CG, 3D, Tutorial, Iris, Sclera, Cornea

Id: 4XFJ4Y41h6E

Length: 17min 20sec (1040 seconds)

Published: Mon Jan 25 2021