HD-DA Fish-Eye 10-17mm F3.5-4.5 ED Ultra Wide Angle Zoom Lens Compact & Lightweight Diagonal fisheye Lens for K-1 II,K-70, KP & PENTAX DSLR Cameras, Black, 23130

Upfront summary: this is the sharpest lens I've ever used for the Pentax K-70. I've had a handful of point and shoots, and a couple DSLRs with multiple lenses, but I finally settled on the K-70 when I determined it had pretty much everything I'd be looking for in a feature set: twin control dials, weather sealing, a fully articulating screen, a dual-axis electronic level, etc. I like going to zoos and natural areas so I knew right off the bat I'd need a good zoom lens. I read some reviews of Pentax's older 55-300 and I was concerned about its noise and slow autofocus, so I'm glad they developed this one, and I snapped it up. From the very first shots I knew this was absolutely a keeper. I don't shoot RAW, and a bit of cropping is about the most processing I do, so to get these kinds of pictures without editing is wonderful. In addition to the 55-300, I've had the 18-135 and the Sigma 17-50/2.8, and I recently got the Pentax 16-85 and the 50-135/2.8. It's possible for me to get sharp images with all of these, but none of those lenses is as reliably sharp as the 55-300. Every shot is razor sharp (except a few due to operator error), autofocus is super fast and rarely hunts, color rendition is gorgeous, and bokeh is great. I shot a good chunk of a (outdoor) wedding and the entirety of a (outdoor) portrait session with this lens, and I'm very pleased with the results. I hope Amazon will add the photo attachments properly, because these images have to be seen (again, zero post processing was used). Just beautiful. If I didn't occasionally need some wide angle landscape and indoor shots, this lens wouldn't leave my camera. My highest recommendation.

If you have a Pentax that supports this lens, it's killer. Not all Pentax cameras support adjusting the aperture from the camera on this lens and there is no way to set the aperture manually from the lens. I'm using it with a K-70 and it's sorta amazing. Very sharp. Auto focus is generally very quick and very accurate and if it needs a manual tweak, just grab the focus ring. No switches required. Auto focus is also extremely quiet. Be nice if it had a wider aperture, but with the K-70's high ISO performance it's not a big deal.The wide zoom range makes it a very useful multitasker. It's the lens that stays on the camera when I'm not expecting to need the camera, because for a grab and go it will likely fill the bill nicely. I have a number of other lenses for specific applications, but this is what I use for long range and getting in tight on action.The weather resistant feature is useful. Had a really bad time with an older 55 - 300 Pentax lens when it started snowing at a track meet last spring. Combined with the weather resistant K-70 camera body it will pretty much work anytime you need it. It's also light and folds up into a very compact package when not in use. The button that releases it so it can be extended for use is conveniently located, so it's not an issue. Botom line, it takes very sharp images, focuses quickly and quietly and is very light.

Carefully tested this lens as I do all new lenses I buy. This sample was was sharp across the frame at all focal lengths by f5.6. Slightly soft in the corners at 16mm at f3.5, but not bad. Autofocus is fast and silent. As with all zooms I've encountered, the internal focusing shortens the effective focal length to focus closer. My estimates of the effective focal length when the lens is set at 85mm and focused at 10 ft it is about 83mm; focused at 5 ft about 77mm; at 3 ft. about 70mm; and focused at the closest distance of about 13.5 inches the effective focal length is about 50mm. Focused very close with lens set at 85mm the image was very sharp and high quality but the area covered was about what you would expect with a 50mm lens not an 85mm lens so it is acting like a 50mm macro not an 85mm macro lens when focused up extremely close. Not a flaw. Every zoom I have ever tested behaves this way. Just do not expect an 85mm macro performer. An excellent lens and the sharpest all purpose zoom lens I have used on a Pentax. It seems to be very well built. I wish it had a marked focusing scale, but otherwise I am very favorably impressed with this lens. I am a very experienced photographer. Be sure to test your sample because there have been some reports on Pentax forums of people getting samples with elements decenterd which would give you images sharper on one side than the other.

This is a high quality lens and quite an upgrade over the stock kit lens. It arrived promptly and in great shape & was new. Please note that the package or box is branded as RICOH Pentax DA. Pentax and Ricoh merged a few years back. As others have noted, this lens is substantially heavier & larger than the stock kit lens. Not an issue unless you are really worried about weight. As far as is it worth it to spend the money for an upgrade over the kit lens? If you are a "regular Joe/Jane" amateur like myself, probably not. If you are a pro, your probably buying $$$$ primes. My old kit lens worked fine & never failed me. I was able to produce very nice photos & many memories with the kit lens. However, I have had the kit lens for over 10 years and took it on many "rough trips" like white water rafting etc and it started to get beat up. The original kit lens still works & takes great photos but I was itching to buy the better lens with a bit better range & specs. This new lens is fantastic and right off the bat I noticed the difference especially on macro shooting. The auto focus is silent and fast. Very happy with the purchase. Now I have the option to use the kit lens on the rough outdoor adventure trips and keep this new lens for my everyday photography & out of harms way. I have been a Pentax camera & lens consumer since 1976 (K1000!) and have never regretted it.