The Thumbnail Grid contains a series of thumbnail objects that represent the search results provided by the Filters Panel. Each thumbnail provides a tone mapped image of the HDRI file it represents as well as some quick information about the file. The Thumbnail Grid will show up to 50 thumbnails at a time. If a search returns more than 50 results you can page through the results using the Next and Prev buttons at the bottom of the Filters Panel.
Search Result Number
The number found in the upper left hand corner of each thumbnail represents its place in the search results. This number can be a useful reference when paging through searches with many results.
The thumbnail image is a tone mapped representation of the HDRI file.
High dynamic range images (HDRI) contain 32-bits of information per pixel. This is a lot of information compared to a typical low dynamic range image which contains only 8-bits of information per pixel. In order to view an HDRI on devices such as standard computer monitors this information has to be compressed into viewable levels. This process is called tone mapping and the result is a low dynamic range image that can be viewed on a low dynamic range device.
Favorites ranking is a way for users to easily identify the HDRI files that they use most often. When searching with the Favorites Filter option checked on the Filters Panel, only HDRI files with a ranking of the selected value or higher assigned to them will be included in the search results. The ranking value ranges from 0-5 and is represented by the number of highlighted stars on each thumbnail. No stars highlighted is equal to a ranking of 0 and all stars highlighted is equal to a ranking of 5. To assign a ranking value, simply click on the star that represents the value you would like to assign. To reset the ranking to 0, right-click on the first star (left side) in the row.
The upper right corner of each thumbnail displays the filename for the HDRI file that it represents. This filename excludes the OpenEXR file extension.
The HDRI filename is broken into four parts, or lighting attributes, separated by hyphens ( - ). We'll use OCTA-0-0-0 as an example to explain this naming convention.
1. [ OCTA ]-0-0-0
The first four letters of the filename are taken from the name of the light style used in the image.
The available light styles are:
[ OCTA ] Octagonal Softbox
[ RECT ] Rectangular Softbox
[ SQUA ] Square Softbox
[ STRI ] Strip (Narrow) Softbox
[ UMBR ] Umbrella (Diffuse)
[ LBOX ] Lightbox
2. OCTA-[ 0 ]-0-0
This number represents the light configuration used in the HDRI file.
The available configurations are:
[ 0 ] Single
[ 1 ] Double Horizontal
[ 2 ] Double Vertical
[ 3 ] Triple Horizontal
[ 4 ] Triple Diagonal
[ 5 ] Array
3. OCTA-0-[ 0 ]-0
This number represents the tone of the light sources in the HDRI file
the available tones are:
[ 0 ] Cool (Temperature)
[ 1 ] Neutral (Temperature)
[ 2 ] Warm (Temperature)
[ 3 ] Sepia (Gel Tone)
[ 4 ] Soft Green (Gel Tone)
[ 5 ] Sunset (Gel Tone)
4. OCTA-0-0-[ 0 ]
This number represents the exposure value offset of the light sources in the HDRI file.
The four available values are:
[ 0 ] -0 EV
[ 1 ] -1 EV
[ 2 ] -2 EV
[ 3 ] -3 EV
When setting up your cubical maps, the brightest light sources will be those with a -0 EV setting. These are designed to be used as primary lighting sources. The remaining values will provide less light to a rendered scene by -1 EV steps. These are best used as secondary lighting and fill.
The Intensity Bar contains four separate light indicators that will be displayed as on or off. These indicators are controlled by the EV Offset Value of the HDRI file they represent. When the EV Offset Value of an HDRI file is -0EV, all of the indicators will be on. This means the file will contribute a maximum amount of light to a rendered scene. For each negative step of EV Offset an indicator will be turned off until only the bottom indicator is left turned on at -3EV. This means that for each step of negative EV Offset, the HDRI file contributes less overall lighting to a rendered scene.