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Sigma 100-400mm DG DN OS — Prime/zoom
Sigma

Sigma 100-400mm DG DN OS

Prime/zoom

86
/ 100
From $999
VS
Tamron 28-75mm f/2.8 Di III VXD G2 wins by 5
Tamron 28-75mm f/2.8 Di III VXD G2 — Sony E · f/2.8 · 540g · $899
Tamron

Tamron 28-75mm f/2.8 Di III VXD G2

Sony E · f/2.8 · 540g · $899

91
/ 100
From $899
Specdex verdict

Tamron 28-75mm f/2.8 Di III VXD G2 takes it — here’s why.

In our weighted Specdex score, Sigma 100-400mm DG DN OS lands at 86 and Tamron 28-75mm f/2.8 Di III VXD G2 at 91. That puts Tamron 28-75mm f/2.8 Di III VXD G2 ahead by 5 points — a decisive margin driven mostly by its strengths in the categories below.

Pick Sigma 100-400mm DG DN OS if…

  • ✓Proven optical formula
  • ✓Weather-sealing (L/GM/S)
  • ✓Strong resale

Pick Tamron 28-75mm f/2.8 Di III VXD G2 if…

  • ✓540g — lightest f/2.8 24-70 alternative
  • ✓Better than first-party G Master at $899
  • ✓Quiet VXD AF motor
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Winner by scenario

Derived from the sub-score breakdown · not a separate test

Sharpness

Tamron 28-75mm f/2.8 Di III VXD G2

Compared on the sharpness sub-score

Tamron 28-75mm f/2.8 Di III VXD G2 leads on sharpness (92 vs 86).

Build

Sigma 100-400mm DG DN OS

Compared on the build sub-score

Sigma 100-400mm DG DN OS leads on build (90 vs 88).

Autofocus

Tamron 28-75mm f/2.8 Di III VXD G2

Compared on the autofocus sub-score

Tamron 28-75mm f/2.8 Di III VXD G2 leads on af (92 vs 82).

Value for money

Tamron 28-75mm f/2.8 Di III VXD G2

Specdex score per dollar at MSRP

Tamron 28-75mm f/2.8 Di III VXD G2 more score per dollar ($899 vs $999).

Sigma 100-400mm DG DN OS 86
vs
91 Tamron 28-75mm f/2.8 Di III VXD G2

Score breakdown

Sigma 100-400mm DG DN OS
86
sharpness 86
af 82
build 90
value 86
Tamron 28-75mm f/2.8 Di III VXD G2
91
sharpness 92
af 92
build 88
value 96

Specs side-by-side

Sigma 100-400mm DG DN OS versus Tamron 28-75mm f/2.8 Di III VXD G2 — full spec comparison
Spec Sigma 100-400mm DG DN OS Tamron 28-75mm f/2.8 Di III VXD G2
Mount
—
Sony E
Focal length
—
28-75 mm
Aperture
—
f/2.8
Construction
—
17 elements / 15 groups
Min focus
—
0.18 m
Filter
—
67 mm
Weight
—
540 g

Sigma 100-400mm DG DN OS

Pros
  • +Proven optical formula
  • +Weather-sealing (L/GM/S)
  • +Strong resale
Cons
  • −Mount-specific
  • −Older AF motor on some
  • −Heavier than modern counterparts

Tamron 28-75mm f/2.8 Di III VXD G2

Pros
  • +540g — lightest f/2.8 24-70 alternative
  • +Better than first-party G Master at $899
  • +Quiet VXD AF motor
Cons
  • −28mm wide-end vs 24mm of Sony GM
  • −No image stabilization
  • −No fluorine front coating

FAQ: Sigma 100-400mm DG DN OS vs Tamron 28-75mm f/2.8 Di III VXD G2

Which is better, Sigma 100-400mm DG DN OS or Tamron 28-75mm f/2.8 Di III VXD G2? +

Tamron 28-75mm f/2.8 Di III VXD G2 scores 91 on our weighted rubric — ahead by 5. Your best pick depends on the sub-scores above.

Is Sigma 100-400mm DG DN OS worth the price? +

At $999, Sigma 100-400mm DG DN OS delivers a Specdex score of 86 — strongest in build.

Is Tamron 28-75mm f/2.8 Di III VXD G2 worth the price? +

At $899, Tamron 28-75mm f/2.8 Di III VXD G2 delivers a Specdex score of 91 — strongest in value.

Does Sigma 100-400mm DG DN OS or Tamron 28-75mm f/2.8 Di III VXD G2 last longer? +

Based on our long-term update and support ratings, both ship with multi-year support. Battery and reliability scores are visible in the breakdown above.

Which is better for sharpness, Sigma 100-400mm DG DN OS or Tamron 28-75mm f/2.8 Di III VXD G2? +

Tamron 28-75mm f/2.8 Di III VXD G2 — leads on sharpness (92 vs 86). Compared on the sharpness sub-score.

Which is better for build, Sigma 100-400mm DG DN OS or Tamron 28-75mm f/2.8 Di III VXD G2? +

Sigma 100-400mm DG DN OS — leads on build (90 vs 88). Compared on the build sub-score.