Both the MediaLight Mk2 and Pro2 platforms meet CIE D65 standards for professional reference environments. The difference between them isn’t about consistency — both are extremely stable and uniform — but about spectral accuracy. The Pro2’s spectrum is an even closer match to the ideal D65 reference, making it the choice for those who need the most precise daylight simulation possible. Whether you’re lighting a grading suite, a DIT cart, or a review space, here’s how they compare.

Designed for Different Roles, Not Different Whites
The Mk2 platform was designed for editors, finishers, and home theater professionals who need accurate, stable D65 light at an accessible price. The Pro2 line builds on that same D65 foundation, engineered for grading, mastering, and DIT workflows where spectral accuracy and inter-source matching are critical.

MediaLight Mk2 v2

• Target SPD: Simulated D65
• CRI: ≥ 98
• SSI (vs D65): ~73
• Exceptional accuracy for all color-critical work
• Ideal for editing, post-production, color grading, and client review
• ISF & PVA Certified
• Color Temperature: 6500K (Simulated D65)
• Professional accuracy at an accessible cost

MediaLight Pro2

• Target SPD: Simulated D65
• CRI: 99+
• SSI (vs D65): ~87
• Closer spectral match to natural daylight — objectively higher fidelity
• Optimized for grading, mastering, and DIT applications
• ISF & PVA Certified
• Color Temperature: 6500K (Simulated D65)
• Premium precision and build quality

About SSI and Spectral Sensitivity
The Spectral Similarity Index (SSI) compares a light’s spectrum to a D65 daylight reference. A perfect 100 would mean a continuous, sunlight-identical spectrum — something no LED can fully reproduce. At ~87, the Pro2 is among the most faithful LED-based D65 matches available today. Most of that improvement occurs in regions where the human eye is less sensitive, but under instrumentation, the difference is measurable.

If you compare the spectral power distribution charts, the Pro2’s curve shows a smoother, more continuous transition across wavelengths, with a reduced emitter spike compared to typical LED designs. Both Mk2 and Pro2 appear equally neutral to the eye, but under measurement, the Pro2 aligns more closely with D65 daylight.

When to Choose Which

• Choose Mk2 if you want true D65 bias lighting for editing, post, or home use — accurate, affordable, and verified.
• Choose Pro2 if your workflow requires the closest possible spectral match to D65 — ideal for color grading, mastering, or environments with multiple calibrated light sources.

While both have the same D65 target, their different spectral profiles can occasionally lead to metameric failure when viewed side by side. This doesn’t mean one is “wrong” — just that the human visual system responds differently to small spectral variations, especially when two accurate sources are compared simultaneously. In typical use, either light will appear neutral, but under direct comparison, sensitive observers might notice subtle differences in white balance or tint perception caused by these spectral distinctions.

For a deeper dive into why spectral differences matter, see Understanding Metameric Failure in Displays and Lighting.