10-18mm F2.8 DC DN for Canon -RF Mount

This review is my first impressions of the lens. I haven't spent a lot of time with it yet, so if my opinion changes, I will come back and update this review.To begin with, I was really happy to find this lens. I got a Canon R7 a few months ago along with the RF 100-400mm lens as I do a lot of birding and wanted a lighter-weight rig for the field than my 6D with EF 100-400mm lens. However, I also like to do landscape and travel photography when on vacation and the occasional milky way or aurora astrophotography shot. The 1.6x crop factor of the R7 makes it really hard to get wide landscape shots. Through an adapter, I tried my 17-40 lens on it that is my go-to for landscapes on the 6D and it was nowhere near wide enough. I needed to be much wider than 16mm on the R7 to get the shots I wanted. I thought the Canon RF-S 10-18mm f4.5-6.3 was my only option and was ready to buy it when I saw the announcement that Sigma was coming out with an f2.8 version. Fantastic! That f2.8 will make a huge difference for astrophotography.I watched it for a while and pulled the trigger on a used one on Amazon from Gabrians (Note the price was good at $549 but the shipping was ridiculously slow- ordered Nov. 29th, arrived Dec. 13th. It was also sent signature required but didn't indicate this anywhere, so I had to arrange a trip to the post office to pick it up the next day as I was not around to sign for it). The lens itself is a nice size and weight. It comes with a small lens hood. I screwed on a UV filter / lens protector immediately and took some test shots. There didn't seem to be significant vignetting with the filter on, which was a pleasant surprise. I was expecting a lot of drop-off at the corners based on other wide angle lenses I have used, but it wasn't noticeable. Even if it was, RAW converters are excellent at fixing that automatically anyway.Focusing is very fast and quiet. So quiet, in fact, that I can't even hear it. I don't particularly like the zoom ring however. Everything about it is backwards from every other lens I have used. It is the further ring from the body, not the closer one, unlike just about every other lens I have. Second, the rotation is the opposite direction of every other lens I have. You rotate it counter-clockwise to zoom in and clockwise to zoom out. That's really the only complaint I have about this lens.The manual focus / multi-function ring works as expected and manual focus override works well with the R7. The lack of image stabilization in the lens isn't a problem since the R7 has in-body stabilization. In my limited testing, the photos came out sharp and I didn't notice any chromatic aberration problems. Close focus is very close. At 10mm it can focus on something pressed right up to the edge of the lens hood.Overall, I give this lens 5 stars for now as it seems like a good lens and fills an immediate need for a fast, ultra-wide angle for crop sensor RF cameras. About the only thing missing from it that I would like is weather sealing for peace of mind.

This is an f/2.8 lens. Canon's version is f/4.5-6.3 for the same focal length. It's also built much more solidly than Canon's cheap plastic lens. The Sigma lens has a metal mount. The Canon lens' plastic mount soon failed to connect to my Canon EOS R5 and R7 cameras. (FWIW, I bought the used Canon 10-18mm lens on eBay with no return allowed. SMH!) The cost to repair the Canon was more than the cost of a new, warranted and better Sigma lens. Buy it right the first time - buy this Sigma lens if you want a ultra wide lens for your crop sensor Canon camera.

Image was sharp, autofocus is fast. The lens is tiny. Build is plastic but does not feel cheap. It a perfect lightweight setup for both aps-c and full frame (ff be mindful it does not cover the full sensors at 10mm, but it active stablization and any sort of cropped from video mode, it more then enough to cover it.

Just what the crop sensor needs for a wide field of view. Fast, sharp and autofocus is fantastic. It doesn’t have IS but the R7 I paired it with has it in the body. Definitely recommend!

Amazing lens and super sharp photos. So happy that Sigma released this lens for Canon.

Very worthy lens

Very light and clear sharp photos