Review on Enhance and Extend Image Quality with Canon EXT. RF1.4X(N) (4113C002) by Rick Alexander

Everyone knows what a 1.4x extension is for, so I won't bore you with that. The quality of this extension is fantastic. Everything is perfect, the glass is great, no flaws, everything is smooth as silk. You can even describe it until you pick it up and immediately understand that it will be worth every penny spent. Optically I see no difference with my RF800 lens. I know there's some pixel-level testing that shows it loses some of its sharpness, but you never see that in the real world. The ONLY downside is that you lose 1 lens stop so you could potentially end up with a noisier image. In my case, however, I use DXO Deep Prime's noise reduction, which cleans it up instantly, and my images are very usable up to 12,800 ISO. It's also hit or miss, but 12,800 is the most impressive. This makes one of those F11 RF telephoto lenses now an F16 lens, but it doesn't matter if you're using good noise reduction software. So if you're considering buying this extension, I'd also recommend getting yourself some good noise reduction software if you don't already have it.