ZBrush 4R5 continues to expand on creative freedom with new features for sculpting, rendering and overall quality of life. These new features were designed to let you be an artist first and foremost, giving you more freedom to explore new ideas!
Major Features:-

Polish by Features – A new set of Polish sliders has been added in the Tool >> Deformation sub-palette to improve your surface and make them cleaner, especially for hard surface models and product design objects. It includes Polish by Features, but also Polish by PolyGroups and Polish by Crisp Edges. DynaMesh functionality has been greatly enhanced and can now retain more of your shape in a lower polygon count than ever before, thanks to the new Polish by Features volume preservation characteristic.

Curves by Features – Creates curves based on the model’s PolyGroups, creased edges or its outline. These curves can then be used with any of the curve-based sculpting brushes.

Panel Loops – Based on PolyGroups, this feature will transform the selected model into individual panels with thickness. Or it can extrude those panels from the surface with clean borders and bevels, perfect for hard-edge sculpting.

Delete Loops – Allows you to remove unnecessary edge loops. At higher settings it can also drastically change the shape of your model.

Align Loops – An alternative to the Delete Loops feature, this produces the same visual effect but doesn’t change the model’s topology.

Dynamic Brush Size – Makes it possible for the brush size to dynamically change as the model moves closer or further away from the camera. This becomes extremely helpful when sculpting items such as bolts, alpha pattern, scales, and etc. No matter the distance the model is from the camera the bolt, alpha pattern and scales will remain the same size due to the brush dynamically changing.

PolyGroup Enhancements – Several functions have been added relating to ZBrush’s PolyGroup options. You can now group by normals, merge stray groups (useful when groups have been auto-assigned), crease or uncrease by PolyGroup and also a Smart Polish By Feature function to improve your mesh shape without losing volume.

Posterize – Posterization takes a smooth gradient and converts it to fewer steps with abrupt changes between them; a staircase kind of effect. With additions made to the profile curves, Material Mixer, BPR Filters and a new 3D Posterize feature, you can now easily create a cell shaded render.

See-Through Mode – Makes the entire interface transparent so that you can see open windows behind ZBrush. As an example, you can use your browser to find a reference image and sculpt against it without even needing to import it into ZBrush!

Auto Save – ZBrush will now periodically and automatically save your work in a temporary project file. It will also auto-save when ZBrush is idle, such as if you’re away from your computer or switch to another application without first closing ZBrush.

Home Page: _http://www.pixologic.com/blog/2012/12/zbrush-4r5-released/