DJI
Osmo Action 4
1/1.3-inch sensor action camera with 10-bit D-Log M and strong stabilization.
$299
Released Aug 2023
Nikon
Z9
Flagship stacked mirrorless with 45MP, 8K video, and no mechanical shutter.
$5,899
Released Oct 2021
Osmo Action 4 is 1.8 years newer.
Wins
Osmo Action 4
Wins
Z9
2 categories tied
TL;DR — Key differences
- BZ9 has higher AF points / zones (493 vs 0)
- AOsmo Action 4 has higher Burst (mechanical) (6 fps vs 0 fps)
- BZ9 has higher RAW buffer depth (1000 frames vs 60 frames)
- AOsmo Action 4 has lower Weight (145 g vs 1340 g)
- BZ9 has higher Burst (electronic) (120 fps vs 15 fps)
Key specs at a glance
Size and weight, to scale
Osmo Action 4
71 × 44 × 33 mm
145 g (0.32 lb / 5.11 oz)
Z9
149 × 150 × 91 mm
1340 g (2.95 lb / 47.27 oz)
Osmo Action 4 is 79mm narrower, 105mm shorter, and 58mm thinner than Z9.
Osmo Action 4 is 1195 g lighter than Z9.
Depth (front-to-back): 33mm Osmo Action 4 · 91mm Z9
Back view, to scale
Width × Height — same proportions as the front of the body.
Osmo Action 4
71 × 44 mm
Z9
149 × 150 mm
Top view, to scale
Width × Depth (front-to-back) — see which body is chunkier on the table.
Osmo Action 4
71 × 33 mm
Z9
149 × 91 mm
Sensor size, to scale
Z9
35.9 × 23.9 mm · Full Frame
858 mm² area
Lens ecosystem
Native lens selection
Osmo Action 4: mount data unavailable
Z9
✓ more lensesNikon Z
90+
native lenses available
Counts include current first-party and major third-party native autofocus lenses.
Use-case scoring
Which one for what?
Algorithmic scores from verified specs · 10 = best in class
Why pick one over the other
Reasons to choose
Osmo Action 4
Burst (mechanical)
6 fps vs 0 fps — higher is better
Codecs
Adds H.264, HEVC
Dimensions (W×H×D mm)
Adds 70.5, 44.2, 32.8
Card types
Adds microSD
Weight
145 g vs 1340 g — lower is better
Reasons to choose
Z9
AF points / zones
493 vs 0 — higher is better
Subject recognition
Adds People, Birds, Dogs…
Codecs
Adds N-RAW, ProRes RAW HQ, ProRes 422 HQ…
Dimensions (W×H×D mm)
Adds 149, 149.5, 90.5
Card types
Adds CFexpress Type B / XQD, CFexpress Type B / XQD
RAW buffer depth
1000 frames vs 60 frames — higher is better
Burst (electronic)
120 fps vs 15 fps — higher is better
Resolution
45.7 MP vs 10 MP — higher is better
Both cameras share
- ✓Pre-Capture / Pre-Release — Both support pre-capture / pre-release
- ✓4K max frame rate — Both 120 fps
- ✓IBIS effectiveness — Both 6 stops
- ✓Weather sealing — Both support weather sealing
- ✓Touchscreen — Both support touchscreen
- ✓Wi-Fi — Both support wi-fi
Pros & cons at a glance
Editorially curated highlights and trade-offs.
Osmo Action 4
Pros
- ✓10-bit D-Log M
- ✓Good low light for action cam
- ✓Affordable
Cons
- –Superseded by Action 5 Pro
- –Fixed lens
Z9
Pros
- ✓45MP stacked
- ✓8K 60p internal
- ✓120fps stills
- ✓Pro build
Cons
- –Heavy body
- –Expensive
- –Large files
Full specifications
✓ = category winner
Frequently asked
Quick answers generated from verified specs.
Which is better for landscape, Osmo Action 4 or Z9?
Z9 scores 9.5/10 versus 1.5/10 for Osmo Action 4 — 45.7MP — excellent for prints up to 24×36".
What's the resolution difference between the Osmo Action 4 and Z9?
Osmo Action 4 is 10 MP and Z9 is 45.7 MP, so the Z9 captures more detail for cropping and large prints.
Do the Osmo Action 4 and Z9 have in-body image stabilization?
Osmo Action 4 does not have IBIS, while z9 has 6-stop in-body image stabilization.
Which shoots faster bursts — the Osmo Action 4 or the Z9?
Osmo Action 4 reaches 15 fps electronic. Z9 reaches 120 fps electronic.
What's the weight difference between the Osmo Action 4 and Z9?
Osmo Action 4 weighs 145 g and Z9 weighs 1340 g, so the Osmo Action 4 is 1195 g lighter.
Do the Osmo Action 4 and Z9 record 4K video?
Osmo Action 4: 4K up to 120p. Z9: 8K UHD (max), 4K up to 120p.
Are the Osmo Action 4 and Z9 weather sealed?
Osmo Action 4: Yes. Z9: Yes.
Which has better battery life?
Rated battery life is 640 shots (CIPA) for the Osmo Action 4 and 740 shots for the Z9, giving the Z9 the edge.
How much does each cost?
Osmo Action 4 launched at $299 and Z9 at $5,899. The Osmo Action 4 is $5,600 less.
Specs sourced from manufacturer data. Use-case scores algorithmically derived. Last reviewed May 2026.
Product images courtesy of DJI and Nikon press materials.