Issue description
When you render an image with the CineRender engine, using bitmap tree images in your project, you notice solid black rectangular shadows appearing behind the tree objects, instead of proper tree-shaped shadows.
Solution
This problem occurs because the Ray Depth setting in the rendering options is set too low to properly process the transparency and alpha channels of bitmap tree objects, this results in the rendering engine being unable to penetrate through enough transparent layers to render tree shadows correctly.
To fix this issue, you need to increase the Ray Depth value in the General Options of your PhotoRendering settings:
- Open Document > Creative Imaging > PhotoRendering Settings
- In the PhotoRendering Settings palette, check the Detailed Settings checkbox to access advanced options
- Navigate to Options > General Options
- Locate the Ray Depth field in the General Options panel
- Increase the Ray Depth value to 10 or higher
- For simple scenes with few transparent objects: use 8-10
- For complex scenes with multiple glass layers or bitmap objects: use 12-15
- For very complex scenes: use up to 30
- Click OK to apply the changes
- Render your scene again using Document > Creative Imaging > Create Rendered Image
Alternative solution for older versions
If you are using an older version where the issue persists:
- Access Options > General Options in the detailed rendering settings
- Set Ray Threshold to 0 for better transparency calculations
- Increase both Ray Depth and Reflection Depth to matching values (10-15)
Higher Ray Depth values allow the rendering engine to follow light rays further into the scene through multiple transparent layers, enabling proper calculation of tree shadows with correct alpha masking.
Note that increasing Ray Depth will extend rendering time but is essential for accurate transparency and shadow rendering of bitmap objects like trees and vegetation.