2008

16 bit/chan Linear (48 bpp) Compresses the luminance selections into 16–bit
color space, at 48 bits per pixel. This is the recommended setting. To
decompress the luminance for use in the scene, set the RGB Level on the
image's
Output rollout on page 5612 to the same value as the linear white value
on this dialog.
8 bit/chan Linear (24 bpp) Compresses the luminance selections into 8–bit
color space, at 24 bits per pixel. This compression method uses less memory
than other methods, but it is generally not adequate to display the range of
luminance in a HDR image, and can result in banding or other artifacts.
Display scaled colors by When on, this value scales the preview image's
luminance value by the specified amount.
L Locks the preview luminance scale to the white linear value. When off,
you can change the value manually. Default=on.
Mark White clamp Masks the white-clamped values in the preview window
with the color indicated by the color swatch. Click the color swatch to change
this color.
Mark Black clamp When Black Point is on, this option masks the
black-clamped values in the preview window with the color indicated by the
color swatch. Click the color swatch to change this color.
HDRI Save Settings dialog
3ds Max can render and save images with 32-bit floating-point channels.
Among the useful applications for this type of imagery are:
■ Compositing: Using 16–bit images in a compositing pipeline can quickly
become a problem as colors are manipulated. For example, banding may
appear.
■ HDR images are not bound to a specific range (e.g., 0-255 or 0-65535);
they have a dynamic range. As such, high-contrast and physically accurate
values can be stored in 32-bit floating-point pixels.
■ Because of their large range of values, HDR images can easily be modified,
and effects can be reapplied long after rendering, without affecting the
quality of the image. For example, changing the
contrast/brightness/exposure of a 16-bit image could cause banding, which
would require re-rendering the image. However, the same operation on
an HDR image should not affect its quality.
7130 | Chapter 21 Managing Scenes and Projects