Premiere Pro 26.5.2 UXP: Lumetri getStartValue() Returns Null for 24 Parameters — Expected Behavior?

Premiere Pro
,
1

During a read-only UXP observation in Premiere Pro 26.5.2 on Windows 11, ComponentParam.getStartValue() returned null for 24 of 130 parameters in a Lumetri Color component (match name: AE.ADBE Lumetri).

The calls completed without reported exceptions. The other 106 Lumetri parameter values were representable by our collector. All 130 parameters reported isTimeVarying() = false.

Parameters returning null

The affected zero-based parameter indices were:

  • 0: Blob

  • 4, 5, 32, 33, 36, 44, 53, 79, 87, 99, 100, 119: Empty or whitespace-only display names

  • 58: Hue vs Sat

  • 61: Hue vs Hue

  • 64: Hue vs Luma

  • 67: Luma vs Sat

  • 70: Sat vs Sat

  • 122: Embedded LUTs

  • 123: Media Embedded LUT type

  • 124: Media Embedded Lut blob

  • 126: Auto Tone Analytics Data

  • 128: LUTAsset

  • 129: LookAsset

Our collector preserves these null returns unchanged and classifies them as UNKNOWN. We do not substitute defaults or assume the corresponding parameters are unused.

Adobe’s ComponentParam documentation describes typed return values but does not appear to explain these null cases.

Questions for Adobe

  1. Are null returns expected for these Lumetri parameters in Premiere Pro 26.5.2? What do they signify?

  2. Is there a documented, supported read-only API for retrieving complete curve, blob, and LUT-related parameter values?

  3. Are some of these entries structural or UI controls rather than readable value parameters? If so, how can an integration distinguish them reliably without depending on fixed parameter indices or display names?

  4. Does getValueAtTime() support retrieving any of these parameter types? What are its limitations?

  5. Are these known API limitations or defects? Is there any version-specific documentation or issue identifier we should consult?

We are developing an integration where preserving existing effect state accurately is essential. We would appreciate guidance on the supported interpretation of these results.

No parameter setters, project mutations, or saves were performed during the observation.

Thank you,

Douglas Christian