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Temporal AA ​

Temporal Anti-Aliasing (TAA) is a real-time anti-aliasing technique that blends the current frame with previous frames to smooth out edges and reduce flickering. Unlike Progressive (which accumulates many frames while the scene is still), Temporal AA works continuously — even while you rotate, zoom, or play animations — making it the primary anti-aliasing method for interactive use and video recording.

Where to Find It ​

This section is located on the right panel, inside the Anti-aliasingAnti-aliasing tab, in the Temporal AA section.

Temporal AA settings

How It Works ​

Each rendered frame is compared to the previous frame. Pixels that haven't changed much are blended together (using the Feedback values), which smooths out aliasing and reduces temporal flickering — the shimmering you sometimes see on thin edges or detailed geometry when the camera moves.

The trade-off is ghosting: if the feedback is too high, moving objects can leave faint trails because the renderer holds on to old frame data too long. The Feedback parameters let you control this balance.

Settings ​

Enabled
Toggles Temporal AA on or off. When enabled, the renderer blends consecutive frames to reduce aliasing in real time. Recommended to keep enabled for interactive work and video exports
Feedback
Two values that control how much of the previous frame is blended into the current frame. The first value (0.88 by default) controls the blending weight for most pixels. The second value (0.97 by default) controls the blending for high-confidence pixels. Higher values produce smoother results but increase ghosting on moving objects. Lower values reduce ghosting but allow more aliasing/flickering
Stable Noise
(Use Total Frame Count)
When enabled, the noise pattern used for rendering effects (like screen-space reflections and ambient occlusion) is tied to the total accumulated frame count rather than being re-randomized each frame. This produces more stable, consistent noise that Temporal AA can smooth out more effectively — reducing the "crawling" noise artifacts you may see on metallic or glossy surfaces

Feedback Values Explained ​

The two Feedback numbers work together to balance smoothness and responsiveness:

First value (0.88)
General blending factor. At 0.88, each new frame contributes about 12% new data while 88% comes from the history buffer. Lowering this (e.g., to 0.5–0.7) makes the image more responsive but noisier. Raising it (e.g., to 0.95) makes it smoother but increases ghosting
Second value (0.97)
High-confidence blending factor applied to pixels where the renderer is very sure the data is correct (no disocclusion, no major change). This higher value allows those stable areas to accumulate more temporal data for maximum smoothness

Default Values

The defaults (0.88 / 0.97) are well-tuned for jewelry rendering. In most cases, you don't need to change them. Only adjust if you notice ghosting on animated objects (lower the values) or flickering on still surfaces (raise the values).

When to Use Temporal AA ​

Temporal AA is most useful when:

  • You're interacting with the scene (rotating, zooming) and want smooth edges in real time
  • You're recording video — Temporal AA provides frame-to-frame smoothing that Progressive can't offer during animation
  • You're working with screen-space effects (SSR, SSAO, SSGI) that produce per-frame noise — TAA smooths this noise over time
  • You want a responsive viewport without waiting for Progressive to converge

Temporal AA + Progressive

These two methods are complementary. Progressive accumulates frames when the scene is still; Temporal AA blends frames in real time during motion. For the best quality, keep both enabled — Progressive handles the final still render, and Temporal AA handles everything in between.