From a development team that pioneered commercial physically-based unbiased rendering over two decades ago, Bella represents the next generation in fast spectral rendering.

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What is different about Bella?

Unlike renderers that employ confusing arbitrary parameters, Bella speaks a more natural language, based on real world concepts and units. This means that in addition to rendering quickly, Bella is also very predictable, allowing you to avoid wasting time with trial and error during scene setup.

Fast Spectral Rendering

Bella's state of the art spectral solvers open a world of visual richness and detail that you have been missing with your RGB renderer.

Optical effects such as the beautiful dispersion seen here, emerge naturally with no need of hacks or workarounds.

Image by Thomas An.

Focus on Performance

Bella's fast CPU solvers can provide performance several times greater than that of even some non-spectral competitors.

Here, we see Saturn CPU producing results similar to Cycles CPU in Rhino 7, but in around 1/5 the time.

The difference can be even greater on MacOS, for renderers that do not yet run natively on Apple Silicon.

Scene available here, and minute-by-minute comparison video available here.

Time: 6 minutes

Time: 17 minutes

Time: 34 minutes

Matchless Realism

Bella's painstaking attention to detail in the models and algorithms we use, results in images with simply better light, and more life.

This is something that cannot be added later on in a project, it must be taken as a fundamental imperative from the very beginning.

Output directly from Bella, no post processes applied. Click here to see an animation of this scene.


Bella's fast Saturn solver is especially suitable for architectural work.

For instance, it handles typical sunlit glass facades with ease, using standard glass materials, with no special setup.

Rendered 5m 11s @ 1080p, no denoising *

Product Viz

4K render test, 1m 36s on a 5950x (model by Nachetz via flying architecture.com)

Bella's Saturn solver makes quick work of product viz scenes.

The Bella Uber material makes it fun and easy to experiment, as you create appealing and unique looks.

Rendered 1m 36s @ 4K, no denoising *


With its beautifully accurate dispersion, Bella is the perfect choice for taking your jewelry work to the next level.

Precious metals and gem materials may be defined using real measured data, with the additional useful option of overriding a gem's natural color.

Image by Thomas An.

Complex Caustics

Bella's Atlas solver easily handles scenes with complex caustics such as swimming pools and the like.

The interesting caustics in this scene emerge naturally by the use of real measured data in the water material.

Rendered 15m @ 1080p and denoised **

Apple Silicon

Though host applications may not yet support Apple Silicon, Bella already supports it natively.

Built as Universal Binaries, Bella applications & plugins provide the best possible performance no matter your type of machine.

Bella for Rhino

Bella for Rhino provides a seamless workflow within Rhino 6, 7 & 8.

You will find cameras, materials, and environments where you expect them to be, working how you expect them to work.

Try it today!

Bella for Maya

Bella's nodal system is quite similar to Maya's, so Bella's nodes are a natural fit to be exposed natively in Maya.

Whether you use Maya 2018, 2019, 2020, or 2022, you can give Bella a try today!

Licensing & Support

Bella's deliberately simple floating permanent license ensures you do not lose valuable time to complicated, error-prone license managers.

Core developers strive to be open and responsive, available to assist quickly & directly with any issue you may encounter.

Try Bella today!

* CPU used for timed examples & comparisons: AMD 5950X
** Image denoised using the integrated Intel denoiser (OIDN).



Thanks to ThomasAn. of Rayflectar Graphics for allowing us to include these images.



Bella has been created to be the type of software that we, ourselves, prefer to use, not only in how the software itself is designed, but also in how it is offered as a product, and in how it is licensed.


We believe in offering a clear and simple product -- therefore, the only Bella offerings are the seat license, which includes all Bella software and plugins, and the node license (reduced cost, for CLI rendering only), neither of which is locked to any particular machine or operating system.


We do not believe in forcing our honest customers to pay the price (in terms of the inconvenience, and inevitable failure of draconian licensing schemes) to protect Bella from unauthorized use -- therefore, the Bella license is implemented as a simple text file.


We believe strongly in respecting your right to privacy -- therefore, Bella neither requires contacting any remote server to validate or register a license, nor does the software attempt to establish any remote connections, at all, during use.

About Us

Bella is developed by Diffuse Logic, a Barcelona-based software company with decades of cumulative experience in the fields of physical simulation and rendering, as well as user-interface design and plugin integration.

Óscar Cano & Albert Martinez

Responsible for our core rendering tech, Óscar and Albert are experts in modeling the complex optical physics involved in simulating the behavior of light, and pioneers in the practical implementation of physically-based rendering..

Jeremy Hill

Jeremy is responsible for our APIs, for developing our applications and plugins, and for creating the systems we use for building and deploying our software.