# HDRI maps High Dynamic Range Images are ultra-high-resolution panoramic images used to build image-based lighting and reflections for 3D environments. ![[Pasted image 20230405090616.png]] _[example image from Poly Haven](https://polyhaven.com/)_ The word [Gamut](https://en.wikipedia.org/wiki/Gamut) refers to the range of possible colors or levels possible between two extremes. Your eyes can see more colors and more levels of light and dark than your camera or your computer screen. That range of light extends beyond what you can actually see, such as infrared and UV light, X-rays and microwaves. Your computer screens capture and represent an even small portion of that range. Paint and printer inks have an even yet smaller gamut of possible colors because they are tied to actual physical properties. Simply put, High Dynamic Range images have a much higher gamut of possible levels than Low Dynamic Range images. Typical Low Dynamic Range images like you get from your camera or the internet are usually 8 bit, have a limited gamut, and only 256 levels of illumination between black and white. This isn’t enough information to capture the full range of lighting in the real world. High Dynamic Range images, on the other hand, store more information per pixel and can be up to 32 bits. The gamut is much wider, from pure black to pure white with over four billion levels between them. This leads to much higher files sizes but also much better lighting and reflections in your rendered environment. Your final rendered images are not going to be the massive 32 bit files, however they will look much better than rendering without HDRI. Also, since an entire image is being used as a source light, you will get much more dynamic lighting and reflections that make your 3D geometry actually feel like it is in a real world. ![[Pasted image 20230405092645.png]] _without HDRI - [image from VISAO](https://visao.ca/what-is-hdri/)_ ![[Pasted image 20230405092710.png]] _with HDRI - [image from VISAO](https://visao.ca/what-is-hdri/)_ --- ## how to use HDRI in maya HDRI maps are actually quite easy to use in Maya. They work with [[lighting - maya lighting|Maya lights]]. First, of course, you will need to download an actual HDRI file to use. There are plenty of good sources out there for free maps. The file format will be an .HDR or .EXR. > [!note]- Sites for downloading HDRI maps… > > - [Poly Haven](https://polyhaven.com/hdris) - free open-source maps, but also textures and 3d models > - [HDRI-Haven](https://hdri-haven.com/) - tons of free HDRI maps > - [IHDRI](https://www.ihdri.com/) - tons of free HDRI maps > - [HDRMaps](https://hdrmaps.com/freebies/free-hdri-maps/) - lots of good freebies, but also paid ones > - [Poliigon](https://www.poliigon.com/hdrs) - a few free maps, plenty of paid ones though We will be using an **Arnold SkyDome** light. Change your menu tab to Arnold and choose the **Create SkyDome Light** icon. Or use the pull-down menus for **Arnold > Lights > SkyDome Light**. ![[Pasted image 20230405130301.png]] Your geometry will be surrounded by a big sphere object that works as a light source illuminating your objects. In the Attribute Editor, you can change a number of settings for things like Color and Intensity. Instead of choosing a Color, click the little checkerboard icon and pick the File option. ![[Pasted image 20230405131933.png]] The interface will be similar but now you will choose the new icon. ![[Pasted image 20230405133310.png]] In the new interface, you will choose the folder icon to get a file picker so you can go choose the HDRI image you want to use. ![[Pasted image 20230405133452.png]] Make sure your view panel is set to render in Arnold. Use the pull-down menus at the top of the panel itself for **Renderer > Arnold**. Sometimes Maya does a weird thing and changes your Color Space back to the default sRGB which doesn’t look so good. Change the Color Space in your File Attributes to Raw for best results. ![[Pasted image 20230405133737.png]] Here’s the results of my demo render with a rubber duck using a regular SkyDome light with white and with a downloaded HDRI map. Quite a noticeable difference, huh? ![[Pasted image 20230405134037.png]] ![[Pasted image 20230405133949.png]] --- Learn more… - [What is HDRI? from VRender](https://vrender.com/what-is-hdri/) - [What is HDRI? from VISAO](https://visao.ca/what-is-hdri/) - [What is a HDRI map? from LightMap](https://www.lightmap.co.uk/blog/whatisanhdrimap/) - [How to Use HDRI Lighting in Maya YouTube video from Academic Phoenix Plus](https://youtu.be/dolCMCmacNw) --- tags: #3d #maya #lighting #resources home: [[! 3d modeling- maya]]