The worst and the the most biggest difference between these two camera is sensor size, the Q-S1 uses small sensor on the other side the RX100 M3 uses a large 1″ sensor, so finally before starting the comparison review we recommend you to go with RX100..
Pentax Q-S1 vs. Sony Cyber-shot DSC-RX100 III Specification Comparison Table.
Megapixel Sony Cyber-shot DSC-RX100 III comes with a 20.1MP 1″ Exmor R BSI CMOS Sensor, Having more megapixels is not bad, you get bit more room to crop your images without any problem,
Bigger Sensor Size: Sony Cyber-shot DSC-RX100 III have bit bigger sensor than Pentax Q-S1.
More AF Points: Both camera feature same contrast based AF system but we get more AF points with Sony Cyber-shot DSC-RX100 III compared to Pentax Q-S1.
Better Shutter Range: Pentax Q-S1 features better shutter range compared to Sony Cyber-shot DSC-RX100 III.
Top Continuous shooting speed: Sony Cyber-shot DSC-RX100 III has fast shooting speed (10 fps vs. 5 fps) compared to Pentax Q-S1.
Pentax Q-S1 Video Mode: Pentax Q-S1 features full HD video recording @ 60 and 30 fps frame rate. HD video recording @ 60 fps and 30 fps.
Supported formats MOV, MPEG-4 AVC/H.264 Additionally, HD 720p and SD 480p formats are also supported.
Sony RX100 III Video Mode: Sony RX100 III features full HD video recording @ 60 and 24 fps frame rate.
Supported formats AVCHD Ver. 2.0 codec is used for highly detailed image quality that translates well to editing and sharing on HDTVs,
Display: Sony Cyber-shot DSC-RX100 III features bigger and high resolution display compared to Pentax Q-S1.
Sony Cyber-shot DSC-RX100 III features 3.0″ LCD Rear Screen tilting (1,288,800 pixels) on the other hand Pentax Q-S1 have 3.0″ LCD Rear Screen fixed (460,000 pixels), so we get more flexibility while composing our shot with Pentax Q-S1.
Battery Life (CIPA): Sony Cyber-shot DSC-RX100 III battery rating is 320 shots and other hand Pentax Q-S1 battery rating is 250 shots. According to CIPA.
Weight: Pentax Q-S1 light-weight than Sony Cyber-shot DSC-RX100 III.
Verdict: We highly recommend you to go with the Sony RX100 M3 camera since the core specification of Sony RX100 M3 is far better than the Pentax..
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