>>> The short answer: Metabones’ naming is inconsistent, and your frustration is justified. But there is a coherent underlying structure — it’s just buried under overlapping labels (“T”, “Ultra”, “XL”, “CINE”, “II”, “II+”) that Metabones reuses in different ways.
🧠The real naming matrix (the part Metabones never explains clearly)
Dimension A: Mechanical housing
T = current housing
(older non‑T housings discontinued)
Dimension B: Optical formula
Ultra = 0.71×
XL = 0.64×
Super16 = 0.58×
Smart Adapter = no optics
Dimension C: Electronics
Mark I
Mark II
Mark II+ (same processor, more memory)
Dimension D: Market segment
CINE = video‑centric firmware + housing
Standard = photo/video general use
Dimension E: Mount
EF→MFT, EF→RF, EF→X, EF→BMPCC4K, etc.
Metabones combines all of these into one long name, which is why the naming feels chaotic.
🧨 Why listings look contradictory
Retailers often shorten names incorrectly. For example, B&H lists:
Metabones Canon EF Lens to RF‑Mount T CINE Speed Booster ULTRA 0.71×
Metabones T Speed Booster Ultra 0.71× Adapter for Canon EF→RF
Both are “T Ultra” adapters — one is CINE, one is not.
The “T” is not a variant of “Ultra”. It’s just always there.
🧵 TL;DR (the part you actually want)
“T” and “Ultra” are not competing labels. You can have both because:
T = mechanical generation
Ultra = optical formula (0.71×)
XL = different optical formula (0.64×)
II / II+ = electronics generation
CINE = firmware/housing variant
So a product named:
EF–MFT mount T Speed Booster ULTRA 0.71× II
means:
EF→MFT
T‑series housing
Ultra optical formula (0.71×)
Mark II electronics
Nothing contradictory — just terrible naming.