Decision tools · Compare

OM-D E-M1 Mark III vs A5100

Quick take: The A5100 has the highest resolution at 24MP; the A5100 is the most affordable; only the OM-D E-M1 Mark III is weather sealed.

16 specs side by side·16 genres scored·UK prices from Wex Photo Video and Clifton Cameras

How to read this page. Highlighted cells win that row on the spec alone. Genre scores are the engine's base scores (enthusiast, photo and video); Camera Match re-weights them for your level and priorities. Price buttons are affiliate links; the price you pay is the same.

Price buttons are affiliate links — GearFrame may earn a commission at no extra cost to you. It never affects a score. Learn more

Verdictwhich should you buy?

A5100 — Casual & Travel: The A5100 is one of the smallest APS-C mirrorless cameras ever made. Its 24MP sensor, phase-detect AF, and selfie-friendly flip screen pack remarkable capability into a shirt-pocket-sized body. No EVF or hot shoe limits it for serious use, but as a compact travel camera or beginner's first mirrorless, it punches well above its price on the used market.

Who should buy what
A5100 (2014)
is the right camera for you if…
  • Beginners stepping up from a smartphone
  • Compact travel photographers
  • Casual vloggers who want APS-C quality
Full specificationsthe better value in each row is highlighted
Specification OM-D E-M1 Mark IIIOlympus · 2020A5100Sony · 2014
Price £446£200Best
Sensor 20.4MP Micro Four Thirds CMOS24.3MP APS-C Exmor CMOS
Resolution 20.4MP24.3MPBest
Video C4K/24p, 4K/30p, Full HD 1080p/1201080p/60p
Autofocus 121-point all cross-type on-sensor phase detect + contrast AF, face / eye detection, Starry Sky AFHybrid phase-detect / contrast-detect AF, face detection
Stabilisation 5-axis in-body stabilisation, 7 stops (7.5 with Sync IS)No stabilisation
Burst Rate 60fps (18fps with continuous AF)Best6fps
Battery Life ~420 shots (CIPA)Best~400 shots (CIPA)
Weight 580g (with battery)224g (body only)Best
Dimensions 134.1 × 90.9 × 68.9mm109.6 × 62.8 × 35.7mm
Weather Sealed YesBestNot weather sealed
Viewfinder OLED EVF, 2.36M dots, 1.48xNo viewfinder
Screen 3.0" vari-angle touchscreen, 1.04M dots3.0" flip-up touchscreen, 921k dots
Mount Micro Four ThirdsSony E-mount
Memory Cards Dual SD slotsSingle SD / MemoryStick PRO Duo slot
Connectivity USB-C (USB PD), micro HDMI, Wi-Fi, Bluetooth, 3.5mm mic & headphone jacks, RM-CB2 remoteMicro USB, Wi-Fi, NFC

Wins the row — price, resolution, burst, battery, weight and sealing are compared; text specs aren't ranked.

How they score by genreengine base scores out of 10
Genre
OM-D E-M1 Mark III
A5100
Portrait
6.7/10
5.4/10
Street
6.2/10
7.0/10
Travel
6.0/10
6.4/10
Wedding & Events
6.8/10
3.5/10
Vlogging & Video
5.2/10
4.7/10
Filmmaking
5.6/10
—
Documentary
6.5/10
4.1/10
Sports & Action
7.7/10
4.7/10
Landscape
5.9/10
5.0/10
Wildlife
7.9/10
5.5/10
Casual
4.8/10
5.2/10
Food
6.8/10
5.9/10
Macro
7.9/10
5.2/10
Architecture
6.0/10
5.2/10
Astrophotography
5.7/10
4.7/10
Fun & simple
—
4.9/10

Scores come from the same engine as Camera Match: verified specifications weighted by what each genre needs, with documented adjustments. The product page and this table show the enthusiast base score. See how scores are calculated →

Next
More comparisons with OM-D E-M1 Mark III
Camera family history