Corona Alpha6 is out!

A new version of Corona is now available. Click here to learn more.

Download the latest version of Corona.

Quick Facts on Alpha V6

• Yes, it is still free for commercial use
• No limitations, no watermarks
• Offers Biased and Unbiased Rendering
• By default very slightly biased
• CPU based
• Fully integrated into 3dsmax, standalone A6 version will follow
• 20k+ downloads for A5
  
• ADD + NBP – Artist Driven Development & No Bullshit Policy

Major new features

Distributed Rendering

A pilot implementation of distributed rendering was added. While currently still having some limitations, it can be already used to speed up your still shots.

Save/Resume Rendering

Yes, with Corona Renderer A6 you are able to save and resume rendering later. Also you are able to save your render and continue rendering on a different machine.

In the future we will also release a utility which will allow you to MERGE two (or more) renders rendered on two different machines (they do not have to part of the same network, so it can be your machine at work and your machine at home).
Resulted merged image will have the noise reduced (simply put: if you used two identical machines, result will twice better)

Improved light solver

Dramatically improved light sampling in some more complicated scenes, where geometry lights and CoronaLights are combined.

Fast motion blur

Non-rigid motion blur is now faster. MUCH faster!

Physically based camera & exposure & emission

Added photographic parameters to the camera, physical exposure, and physical light emission units.

Rayswitch material & texture

Rayswitch material and texture added, allowing entirely new artistic tweaks in Corona renders. Use it to create materials invisible directly from camera or not affecting GI, reduce or increase color bleeding, and more.

Support for 3ds Max standard/photometric lights

While the standard 3ds Max lights are nowhere as physically plausible as CoronaLights, we understand that some users like them for their unprecedented artistic control ability. That’s why we are bringing them to Corona.

Internal Color Space is now WIDE RGB

Why?

Corona Renderer was previously using the XYZ color space, as opposed to the sRGB color space used by most renderers.  There are several reasons why using wide-gamut color space improves rendering, even though the final rendered image is converted back to sRGB.

The most important is that input material colors are interpreted differently, in much more plausible way. We all know using pure white (RGB 255 255 255) or pure black (RGB 0 0 0) colors is bad (one makes the render times skyrocket, other creates “black holes” in the image. No real object is totally white or black). An sRGB renderer actually faces these same problems every time a color with either 0 or 255 in red, green, or blue is used (for example, pure red, RGB 255 0 0). This means that using such materials will increase render times, and can also create entirely black objects when differently colored light is used.

When using wide gamut color spaces, all color components are converted to not so extreme values internally. This “magic trick” causes the result to look identical under normal, white-ish lighting, but much more plausible when colored lighting is involved.

A secondary effect is that certain phenomena, like low kelvin temperature emission, or physical sun/sky models at sunset, that are out of sRGB gamut, can be easily simulated with wide gamut spaces.

Although the XYZ color space gave good results according to our empirical testing, using it was not theoretically correct, because the color space is not closed under multiplication (meaning it can produce non-existent colors). That’s why we have decided to switch to Wide gamut RGB, which does the job equally as well, is theoretically correct, and slightly more predictable.

 Look at the examples below: 

All clear? Let’s move on.

Support of third-party plugins

Corona Renderer A6 does support the following plugins:

• All 3ds Max procedural shaders
• MultiScatter
• Multitexture
• Forest Pack Pro
• Forest Color
• RailClone
• BerconMaps
• MDO
• ColorCorrect
• Mighty Tiles Pro
• …

UI changes

Main Settings UI

The GUI was improved, cleaned up, some options were renamed/reworked to be easier to use.

Tooltips

• Added tooltips for the key parameters, activated automatically when you hover over the controls. They replace the previous online manual that was not updated since Alpha v4 and remove the need to switch out of the application to look into manual.

• Inactive parameters are now automatically disabled in the GUI

CoronaLightMaterial

• Emission was moved from CoronaMtl to the new CoronaLightMtl.
• Self-illumination was added to CoronaMtl.

Render Elements Reworked

• Similar ones were grouped together.
• There is now a canonical way to compose the final render from elemental passes: by adding up all CESSENTIAL passes.

Minor features

• Added albedo render element, showing total material reflectivity. It can be used to quickly check if a scene doesn’t have too bright materials, which would cause excessive render times:

• Cylindrical/disk and targeted Corona Lights

• Added include/exclude option for Corona AO:

• Option to include/exclude individual objects from illumination for each light
• Scenes now render fast with arbitrary portals polycount
• Inteligent masking – “Render Masks Only” button (non shading render elements only)
• Renderstamp now supports more fields: computer name, frame number, and more.
• Support for XRef scene

Major bugs fixed:

• Fixed issues with Multiscatter, Forest pack randomly not working
• Fixed crashes of Corona VFB with some resolutions
• Fixed extremely slow rendering in some scenes
• Fixed crashes when using HSDS modifier
• Fixed problems with texture filtering inconsistency
• Fixed shadows artifacts when using transparent objects
• Attenuation now works correctly with glass without caustics
• Fixed occasional jagged edges behind glass and camera motion jerks

I am pretty sure that we forgot on some things, but you are welcome to ask us here,
on our forum, or on facebook. Now that you know what cool features are included in Corona Alpha v6, get it here after registering.

Adam & Ondra