For a full review of the Canon G1X Mark III, see the comprehensive hands-on review.Here is the summary of the CameraLabs review of the Canon G1X Mark III
The Canon G1X Mark III is a unique camera, squeezing a large APSC sensor – the same found in the EOS 80D and EOS M5 models – into a relatively compact weatherproof body with a 3x optical zoom, built-in viewfinder, fully-articulated touchscreen, plenty of manual control and excellent wireless capabilities. The sensor also boasts Dual Pixel CMOS AF, allowing it to smoothly and confidently refocus for stills or movies. These all make the G1X Mark III one of the most powerful compacts to date, but there’s still no 4k video, nor microphone input, and the big sensor also makes it one of the most expensive compacts around. Revealingly its rivals with smaller 1in sensors typically couple them with brighter lenses, allowing them to roughly match the G1X Mark III on resolution, noise and potential for background blurring, but there’s no arguing with the APSC sensor’s superior dynamic range, allowing the G1X Mark III to capture a greater tonal range and more saturated colours. Don’t underestimate the appeal of squeezing the photo and movie quality of the EOS 80D into a compact weatherproof body weighing less than 400g either. The G1X Mark III may have some annoying omissions for movie shooters, but remains one of Canon’s most compelling compacts appealing as a standalone camera or a companion to larger DSLRs.