Canon PowerShot G9 vs Canon PowerShot S120

Specifications at a Glance

• Canon PowerShot G9 – Released 2007, 12.1 MP CCD sensor, 6× optical zoom (35–210mm equivalent), f/2.8–4.8, 3.0" LCD, RAW support, optical IS, powered by NB-2LH battery.
• Canon PowerShot S120 – Released 2013, 12.1 MP CMOS sensor, 5× optical zoom (24–120mm equivalent), f/1.8–5.7, 3.0" LCD (touchscreen), RAW support, optical IS, DIGIC 6 processor, powered by NB-6LH battery.

Overview
Both cameras represent different eras of Canon’s compact lineup. The PowerShot G9 was a “prosumer” compact built like a small DSLR, offering solid manual controls, fast image handling, and excellent pairing with underwater strobes like the Ikelite DS51. The PowerShot S120 was a pocketable high-end compact with modern CMOS technology, wider angle coverage, and strong low-light ability — making it a travel-friendly choice that also worked well underwater. From our dives, the G9 felt like a dependable, quick shooter, while the S120 delivered portability and low-light strength, but lagged behind in shot-to-shot speed.

Image Quality
G9: Produced sharp, brilliant images with rich color depth when paired with the DS51 flash. Its CCD sensor gave images a pleasing tonal quality, especially in blue water.

S120: Thanks to the CMOS sensor and DIGIC 6 processor, it performed better in low light without flash. Images were clean and bright, even during deeper dives or dusk. However, they sometimes lacked the crisp brilliance of the G9’s CCD output.

Performance Underwater
G9: Surprisingly quick for its time. Image processing and write speeds were fast and reliable, allowing multiple shots in succession. With the DS51 strobe, it was a consistent, no-nonsense workhorse.

S120: Faster autofocus and better low-light ability made it easier to capture ambient-light shots. However, its slow write times were a real frustration underwater — after each shot, the delay could make capturing fast-moving fish nearly impossible.

Handling & Housing
G9: Bigger and heavier, but once in the Ikelite housing, the large controls were easy to operate. With the DS51 strobe, it felt like a serious underwater photography kit.

S120: Much smaller and lighter, which made it easier to travel with. In the Ikelite housing, the controls were compact, but sometimes harder to manage with gloves.

Strengths

• Canon G9: Excellent sharpness and color, reliable flash integration, fast image processing, robust housing setup, consistent results.
• Canon S120: Great low-light performance, wider 24mm angle, compact size, faster autofocus, better portability.

Weaknesses

• Canon G9: Bulkier system, limited high ISO performance, older LCD resolution.
• Canon S120: Slow write times, less brilliance compared to G9 CCD output, smaller housing controls.

Verdict
Both cameras served us well underwater, but in different ways: The Canon PowerShot G9 remains our favorite for overall reliability, fast image handling, brilliant sharpness, and seamless strobe use. It gave confidence on every dive and captured moving subjects more effectively. The Canon PowerShot S120 stood out for portability, speedier autofocus, and low-light ability, making it a fine travel companion. But its frustrating write delays meant it could not match the G9’s responsiveness underwater.

👉 In the end, if we wanted fast, consistent, and brilliant underwater results, the G9 with DS51 flash was unbeatable. The S120 was a convenient backup, but the G9 stayed the true favorite.