PENTAX 50 mm f1.8

This is an excellent little lens very well worth the about 305 EUR you can get it for new here.Even though it clearly is an APSC only lens I did buy it for my Pentax K-1 FF camera as light vacation/travel tele option.The lens when folded together is just about the size of the fantastic Pentax DFA 100mm F2.8 macro lens,so while certainly being no pancake it is very easy to transport in very small bags.The build quality is very ok for this price range and certainly better than Tamrons.The optical quality is great, especially at the important long 300mm end. Certainly not on DA* 300mm prime level (who would expect this?) but good enough for 60x40cm prints.The new PLM lens AF drive is really very silent and quick. I find it preferable to old SDMs, Sigma DCs and HSMs.Focussing with it is very fast, especially if the change of focus is not between ultra close and infinity. I'd even might give it a try in sports subjects.This PLM drive has the same functionality as the "STM" drive from Canon: It can make very small adjustments silently during video capture.What is also worthwhile noting is that this is the first Pentax lens that I know which is "focus-by-wire", so there is no direct physical connection between the focus ring and the lenses. So when the camera is powered off you can not adjust focus. Pentax calls this "power focus".It features the new KAF4 mount, which means the aperture is not controlled via physical level from a little motor in the camera body but the lens has its own aperture motor. In order to use this you do need one of the newest models K-3II or K-1 or K-70, K-S1, K-S2. Otherwise the aperture will be fixed and you can not really set it.As already mentioned: I use it on a FF body. The strongest hard vignetting is between 78-88mm with only small parts of the corners being shaded at both 300mm and 55mm. Especially at 300mm I usually do crop somewhat anyway to that is not a major loss. Also my zoom lens usage usually means that I use the lens at one of the two ends, so that seems to work fine. Even at the worst vignetting 88mm when using square crop (25 MPx) no vignetting is left on the picture. Together with the Pentax DFA 28-105mm lens this should make my preferred light FF travel combo.Fully recommended.

I bought this for my wife's K20D camera when it appeared in an Amazon deal. I'd been discussing prime lenses with a relative (who heads a photographic society) and was interested to see whether all the breathless enthusiasm was justified. The short answer - it is!The K20D is getting to be fairly old-tech these days, but is still a force to be reckoned with as SLRs go, with a decent sensor density and in-camera processing that yields remarkable images, especially when it is teamed up with the right lens - which is where this comes in. I recently bought a 50mm FX prime for my smaller-sensor Nikon D80, expecting to get similar results to this Pentax lens, and realised that sometimes the lens shows up the limitations of the camera. Not in this case, though. The K20D may no longer have market-leading sensor density, but it definitely benefits from this excellent lens, and if your camera is anything near 16 megapixels or above, you will notice similar or even more spectacular results.In use, the lens is very quick to focus because the components are very light - there is no "hunting" either side of the actual correct focus as you get with larger lenses and, unlike my Nikon 50mm prime, it is quiet in operation. It's a small difference, but if you've been using long zooms or telephotos for your photography, the snappy focus of small lenses like this is a revelation.The quality of images is the point, and having fewer lens elements goes a long way to eradicating the small errors that creep in with all but the most precisely engineered lenses - you can get better quality for less simply by leaving things out, which is the attraction of prime lenses. Where this lens really stands out (as better than my Nikon equivalent) is in the depth of field effects and the quality of bokeh (the arty blurring of backgrounds) that I believe stems from the iris petals, which are subtly curved.As is uaul for prime lenses, especially 50mm, you need to pay quite a bit of attention to depth of field and focus, which are more critical for 50mm lenses where the DoF can become very narrow in close-up, and really highlight out-of-focus areas - if you're taking a shot acrosss someone's face and can see both eyes, it comes down to the point where you have to work at getting both eyes in focus by managing the aperture very carefully (and where depth-of-field preview becomes essential). In that senses, lenses like this, used carefully and thoughtfully, make better photographers of us all.It may be a bit of a bind to zoom with this lens, since that involves walking towards and away from your subject (!), but the results are definitely worth looking at.

As an enthusiastic Pentaxian (several cameras and lenses) I waited for the price of this amazing lens to drop down before I bought it. Like all my Pentax lenses it is well built and has great optical quality. Do not be put off by this models light weight or that it has a plastic rather than a metal mount. It still works the same. I bought mine in December so I have been able to test it out. I really works well in low light conditions (the reason I why I bought it).I already have an older Pentax M series 50mm f.17 lens that performs superbly on modern cameras ( fits straight no to All Pentax DSLR'S and other makes with a suitable adapter) despite being more than 30 years old but as my eyes get older focusing manually all the time (as you must with any M series lens) I don't always nail the focus point each time. With the DA50 focusing is very fast, smooth and always spot on. A real joy to use and no missed shots. Another difference between the DA and M series 50mm is in the number of aperture blades. The DA has 7 whereas the M has 6. The DA therefore is the better lens when it comes to blurring the background for instance when taking portraits or close ups.Many people prefer the also brilliant DA35 f2.4 which costs slightly more but for my money this is the lens to go for.