Sigma 70-300mm f/4-5.6 DG Macro Telephoto Zoom Lens for Pentax SLR Cameras

I have been using DSLR's for about 5 years. I started with the Canon t3i and when I wore it out I decided to move to Pentax with the K-5IIs. I chose this lens for it because it was both in my price range and had good reviews. That was the best choice I could have made! This is a top-notch lens, especially for the price. I had the long zoom kit lens for my Canon and it was loose and not near the build quality of this lens, nor was it as crystal clear. This lens allows the camera sensor to get the best information possible. I simply cannot say enough good things about it! The only annoyance, as others had noted, was that to zoom past 200mm you have to flip a switch, but its not the end of the world and you get used to it. I literally cried with joy at the images I could get with this. It is quick to focus, stays in the position I put it, is crystal clear, and oh the bokah! Depth of field is amazing, and I am convinced to get a shorter range Sigma for close-up work. You won't regret purchasing this lens. All the photos I am including were taken in low light on a cloudy day late in the afternoon or inside a building with no lights on. No flash was used, just the camera, lens and I.

I bought this lens based on reviews here and my budget. I was just stepping up to a DSLR and wanted a long reach lens but I didnt have the budget for much. I went back and forth between the Sigma and the Tamron and ended up with the Sigma, again based on reviews here.The Good:This is a great starter lens or budget lens. With a 1.5 crop factor it is a 105mm-450mm lens with true macro from 200-300mm (250-450 converted). Thats a lot of lens for $150. The macro is good but takes some getting used to. First you have to go past 200mm, then flip a switch to go to macro focusing. When you are done, you have to do all of that in reverse or it wont retract. The macro focusing is good but most of the time you will want to switch to manual. The zoom ring has a nice positive feel that lets you stop when you want to and go when you want to. Some zooms are a little too "lose" for my taste. Because of its size, hand held shooting needs daylight and even then if you can use a tripod, do. With a tripod, the sharpness is excellent. This lens has a definite sweet spot between 135mm and 200mm, f/8. Shoot in this range and you will get amazing results.The BadThis thing is BIG and HEAVY. At 300mm and the full macro focusing, this lens is HUGE!! Do not try using it on a cheep tripod. I did, its frustrating. Because of the size and weight, it flops around more than some lenses. BE CAREFUL! Focus at either end is not a strong point. There is softness and CA at 300mm and at the low end of the f-stops. IF you can shoot f/8 or better, you will get better results.This is not a "digital" lens. It is a full frame, 35mm film lens that works great on new Pentax digitals. AS long as you understand and accept its limitations, you will get a lot of value from it.

I got this lens as a present around Christmastime, so I've only been using it for about 6 months now. It's a very sturdy lens, and works well with my Pentax K-x camera. It comes with a hood, which is really great.I haven't used it too much, but when I need this lens, it gets the job done the way I want it.I would say my only complaint about this might be the ease of use putting it on my camera. Sometimes it slips right on, and sometimes it can be very difficult. I don't have a problem changing between any of my other lenses, but sometimes this one can be a little tricky if it isn't lined up EXACTLY right.Overall, I'm very happy with this product.

Honestly, you get what you pay for. I'm not going to pretend this is the end-all of lenses or that it blew me out of the water. It's a very acceptable zoom lens for a very very decent price. I've been very impressed with the quality of Sigma's optics, and this is no exception. The lens is very clean, very crisp, and takes very nice photos. That said, the zoom is slow and noisy, and autofocus tends to just derp hardcore sometimes. When focusing on a very close or very far object, it will often zoom all the way in and out a few times attempting to focus on the object. These are all things I'm willing to accept for the price I paid. Pictures in the 80-150mm range come out very crisp and the lens is decently fast. 150-300mm definitely will require a tripod or other sturdy object unless it's very bright and you're shooting at 800-1600 ISO. It's good introductory lens and a great add-on to any Pentax K-5 K-7 or K-30 kit. All the negatives aside, I've taken some fantastic photos with this. It's done very well for daytime shoots of wildlife and I've gotten many "national geographic" type photos with it.The bottom line: If you wan't to be blown away with ultra-crisp photos at low ISO at 300mm, this lens is not for you. If you want a decent zoom lens that you will use with a tripod and mostly for daytime-use at a low low price, get this lens!

This was my first zoom lens and has been a spectacular buy. I went out that first day and took an award winning photo of my street which included my neighbors American Flag flying in the breeze. I sent that photo to dozens. I'm surprised I haven't seen it on YouTube yet. Haven't tried the close up macro mode yet as my arms are just too long.Would I recommend this lens to others? You bet. It is really a winner and well worth the money. I can't believe it was so inexpensive. If you're in the market for your first "Biggie" Zoom Lens, give this one a try. You'll be glad you did!

The lens is just a bit over a year old and I am already having problems with the auto focus and apature working. All the other lens I have for my camera work just fine so it is a lens problem. I haven't decided yet if I will have it repaired as sometimes the repair cost is half the price of the lens. I expected a lot more from a Sigma lens.