When specifying a frame set to render, you can now specify partial frames. For example, to render at a time 20% of the frame length from frame 7 to 8:
7.2
See Render Pass Property Editor
There is also a corresponding file name template token. When rendering partial frames, you should use the [PartialFrame] token in the file name template because the [Frame] token gets rounded to the nearest integer. See Tokens and Templates.
There are now three possible settings to control when the render region refreshes: Interactive (the old Auto-Refresh = on), Camera, Time, and Region State (the old Auto-Refresh = off), and the new Manual mode. In Manual mode, render regions never refresh automatically and you must always refresh manually.
Other Render Region Preferences
The render region preferences have moved to their own Region tab in the Rendering Preferences. There are several new options: Draw Tile Borders, Clear Rendered Image on Interaction, and custom colors for various interface elements.
You can now specify the new High Quality mode as the Render Type in the Hardware Renderer Property Editor. Framebuffers are not supported — you can only render the main channel.
Irradiance Particles and Final Gathering
You can now use irradiance particles together with final gathering. However, the final gathering settings take precedence over the irradiance particle settings. In particular, the irradiance particles' Intensity and Interpolation settings are not used. See Using Irradiance Particles with Final Gathering.
AngularVelocity and Motion Blur
The AngularVelocity attribute works correctly with values beyond +/-360 when rendering motion blur.
Local rendering options now show the label "Local" as well as appearing in Roman typeface in the explorer. This distinguishes them better from global settings in Italics. See Setting Global or Local Render Options.
When rendering with mental ray and Premultiply with Alpha turned off on the Framebuffer tab of mental ray Render Options Property Editor, RGB values not longer get clamped to 1.0 for floating-point images.
Similarly when using the PreMultiply in the Fx Tree to unpremultiply, RGB values no longer get clamped to 1.0 for floating-point images.
