Canon RF 24-105mm F4-7.1 IS STM for underwater photography - the overlooked flex lens in the RF system

Hi everybody,

while well served at the super wide end with the Canon EF 8-15mm fisheye + Teleconverters (FCP at a more compact size and reasonable price) and having the currently best full frame Macro in the industry with the Canon RF100 USM; I was looking into a mid-range flex lens in the middle for that little kick of flexibility.

I was even looking into buying an old SIGMA 17-70mm for EF mount, which had this amazing close focus an Macro ability in the DSLR era and was used by many shooters behind a dome.

While researching options I stumbled across Canon‘s very own RF 24-105mm F4-7.1 IS STM that was launched + bundled together with the RF mount R6 cameras a while ago. Compared to it‘s much more expensive sister the RF 24-105mm USM which is not really attractive for underwater use it features dent sharpness and much less travel weight on land.

So I bought myself one and also tested it heavily against the widely for UW shooters recommended RF 24-50mm STM shard by Canon.

The winner is certainly the RF 24-105 STM which offers very decent close focusing distance and even some macro capability.

You can use this behind very large 9 and 8 inch domes, but also it is a very interesting candidate for water contact optics.

Behind my Ivanov Optic I can use it from 24-75mm or 32-85mm depending how I set up the extension rings. This might not be useful information for others,… as this underwater lens is simply not available for sale anymore,… but,…

I think it has high potential for Canon RF underwater contact optics use, when you are willing to ditch the 24-27 zoom range and start using it at the 28mm focal length. With water contact optics, I am referring to the Nauticam lineup and the shortly available Marelux Aquista 100 and Marlux Aquista 120.

The sharpness Sweet spot of that lens in land tests is at F8.

I wonder why this baby has not made it into many manufacturers port charts.

Hopefully we can bring this up on the radar of gear makers.

PS: zoom gear of the RF15-30 STM fits also this lens 🫶✅

But to avoid people using the 24-27mm range or extruding the lens too far out, housing makers might want to produce a gear with Zoom-limiter to perfectly match their water contact optics best results.

Edited 3 hours ago3 hr by Adventurer