Best walkaround lens ever made.
583677
My thoughts:

- It's sharp at the center at all apertures and at all focal lenghts, however it falls short on the edges ("sweet point" at f10 or f11, IMO)

- It's a very contrasty lens.

- The VR system works very very good (Im able to get steady handheld shots even at 1/1.3s)

- It's well-built, solid and reliable.

- The autofocus speed is very fast and accurate.

- does the lens creep? Yes, it does (sometimes) but I really don't mind it.

- The 11.1X zoom is unbeatable, better than any zoom ever made, and it's faster at long end than the Sigma or Tamron ones (f5.6 vs 6.3)

- It's a highly recommendend lens, no doubt on it.

- Some sample images at full resolution taken with D50 can be found on the link below:

[...]
4876429
The best walk around, flexible zoom, portrait, low light, lightweight, L-Glass quality USM lens from Cannon.
The color is fantastic, even compared to 17-40 F/4.0L.
2537069
I am no professional with 50years of experiance, but 49 years of hobby photography, now retired for many years, and doing this every day for elder exercise hbby, this is a spectacular lens, very happy with it on my Nikons D 60  D 7100 and slightly different camera and 50mm lens on mynikon D3x,  glad i made the purchase, when i learned that it was a ( walking lens ) thought they meant set it down and it walks ,,WELL DAH ! it loves walking and i do to, very good lens, you must have one,it would make a brilliant present... J R Massachusetts
550074
the most perfect lens, matching my Canon 70D to produce outstanding pictures. the zoom is so useful, capturing any conceivable scene, from a little bee on a flower to an eagle high in the sky
1992218
I have used this lens for quite some time now I have used it on an old D50 and a brand new D300s and the result is the same...Pure amazement. I love this lens, I carry it everywhere it works great in low light, it focuses several times faster than my $850 18-200mm Nikkor lens. Amazing brokeh superb DOF ranging from very shallow at an amazing f/1.8 to as deep as you could ask for at f/18+ I can't say enough about this lens. Nikon has been producing this lens for a long time and I believe has reached perfection. Lightweight, portable and durable what more could you ask for. It's great being able to shoot at f/1.8 at 55mm rather than 3.8-4.2 with zoom lenses. I have used the 35mm, the 105mm and even the very expensive 55mm f/1.4 and I still use this more than any of the others combined. It's fantastic, don't look any further just buy it I promise you'll love it. For great info and if your still skeptical go to ken rockwell's site and search for it. It made his top ten nikon lenses to own and there is no disputing it here.
1674729
Absolutely beautiful lens, straight forward, no quirks, just photography. Big, heavy, smooth and gorgeous.

Produces stunning images on both my D7000 and F100. The Bokeh at 2.8 is beyond creamy.

Sharp as a tack all throughout.

If you're shooting strobes, you don't need VR anywho, so save yourself from spending an extra 1000 bucks on a 70-200 VR I/II and pick this up.

Take a deep breath, and squeeze.
1021232
First of all, to the previous reviewer who called this a "rubbish lens," because it has "the most serious distortion I have ever come across,":  did you really just pay hundreds of dollars for a fisheye lens without knowing what a fisheye lens is? Seriously? In case anyone else is confused, this lens is nothing like a normal lens. It provides a warped image which, when skillfully composed, can be quite unique and interesting (see the example images on the description page).

The Sigma 15mm Fisheye lens is well-made and provides sharp images. It has an aperture ring which locks in the f/22 position for use on modern cameras which set the aperture electronically. The lens cover is a sleeve which slides over the build-in lens hood. Oddly, there is a removable lens cap on the front of this piece. I don't know why you would ever remove the cap and leave the sleeve on, as this results in serious vignetting.

I enjoy this lens because of the new creative opportunities it provides. I love how you can get so much context around your subject, but beware, objects in the viewfinder are closer than they appear. It's easy for your pet or child to put his wet nose on your lens (which you can't protect with a filter). I recommend this lens for the photographer who has everything. You won't use it on every shot, but it offers a whole new perspective on the world.
3351328
I was aware of the comments surrounding the prior incarnation of the Sigma 50-500mm and how it was just short of amazing.  When this version was introduced, I bought it immediately, without waiting for reviews, as I suspected Sigma paid attention to comments and made the lens what it should be.

This lens constantly blows me away for what it can do.  I could go extreme geek. but I'm more interested in relaying this lens' usability.  It's ridiculous zoom range actually works - on the right camera.  The Nikon D90 I paired it with would do a decent job, but the pictures, although sharp enough, lacked contrast.  The new Nikon 7100 is a perfect match and the extra megapixels give you crop factor that allows for great images even if they are enlarged 50% or more.

And it's sturdy.  I dropped this lens so hard, I smashed the filter into the mount, covering the front element with shards of glass.  I had to take it to a camera store to have them remove the filter frame.  The lens continued to perform even after that fumble.

The perfect backpack for this lens with (my) camera attached is the Lowepro Flipside 300.  I've bicycled around with that backpack lens combo.  Has a waist strap to support the weight.  Yes it is big and heavy.  But for what you get, the weight is worth it.  And a Blackrapid camera strap attached to the footplate of the lens helps balance the lens.

I used this lens yesterday on a boat pitching in 30 knots of wind photographing a regatta.  The optical stabilization just works, and it works hard to give you great pix.  I've used it shooting surfers and the autofocus is fast enough to stop the action.

When the zombie apocalypse comes, this lens will going into my bailout bag. I'm a working pro, billing 10k in the last three weeks and no, I won't tell you what I do.  I USE and trust my lighting and gear and won't have any crap lenses or equipment in my quiver; if it doesn't work, I send it packing.  This lens makes the grade.  I can't say enough about this lens.
1984631
I bought this lens just before my wife and I left for a Caribbean Cruise. I took this lens along and a couple of other excellent lens I have on the cruise in early 2013. This lens did a beautiful job and I never used any other lens out of my bag including my 75 to 300 zoom G lens I have, I had some stunning shots I was very proud of. There were a few times I wished this lens zoom could reach further than the 50 mm maximum such as 75 mm. It's fast with f/2.8 The quality and colors were just magical. It really enhanced our cruise experience.
Here is a cruise tip; Around 2 or 3 in the morning ships become virtually a ghost ship. The sky, the lighting on the decks, hot tubs and pools are all working but nary a person getting in the way of your beautiful shots. You find yourself in a position to freely roam around the ship without people interfering with the photo-time. It has a sharp clear image, well done color saturation and fast which helps you get the shot in low light.
823498
I wanted to wait a couple of months of use before writing a review for this lens.  I am a novice photographer, and wanted a lens mainly for portraits. It was between the 85mm and this one and I made the right choice. The first thing you'll notice when you first hold the lens in your hand is the build quality.  Its heavy enough that it will tire you out handheld for long periods of time.

This lens is super sharp.  I used this with a Canon 6D and I absolutely love it.  This is the one lens that once you have it, you hold on to it forever.  I love the bokeh, it super soft and creamy it just brings your subject forward.

If you are on the fence, go for it. You won't regret it.
772774
Outstanding. Simply outstanding. This is probably the sharpest lens I have every owned. (I've own a bunch including Nikon, Leitz and Zeiss on a Hasselblad). Its fast, easy to hold, well balanced, focuses quickly, IS works well and it is Sharp. Edge to edge sharp wide open or stopped down all the way. It is a big lens about 5" long and weighing nearly a pound and a half. The lens focuses quickly thanks to the focus limiter switch. In macro you will want to focus manually. Besides macro work it is an unforgiving portrait lens - seeing every pore is not always the best thing. Its size and heft machete a little intimidating. Just as an FYI DxO (they test and ran optics) rates the Sony 90mm f/2.8 as the 2nd best lens out of their work of 4,500 lenses. IMO its worth every penny.
2682787
A rarity these days, an exceptionally well made item. I am a professional Photographer and know great glass when I see it. The lens is crystal clear, perfectly ground and polished. The mount is retro and rock solid. The handle perfectly cast, milled, plated, and finished. I would highly recommend this fine product.
1891828
Don't worry that it's not the mark II of this lens. Even without the image stabilization, this is easily the best lens I've ever had the pleasure in owning.

I picked up this lens to take sports photographs for my old high school in the beginning of the 2017-18 school year. I definitely wanted to get Canon's newer version, you know, the big almost two grand lens with the image stabilization and improved focus, whatever. But with a deadline, I had to grab what I could, worried that I would have to settle for a lens that's 15 years old (According to Amazon?). Luckily for me, I didn't have to settle, this lens outperformed on any person I put in front of it. At f/2.8 it lets so much light in that on a Canon 6D I never had to worry if (because of the lack of image stabilization) if my shots were slightly blurred from my movement. I could run 1/200 second, f/2.8 and auto ISO (limited to 50-6400) and I had perfect depth of field, focus, and almost no noise, and any noise I did have at 6400 I could easily correct in post with the 6D's high ISO capabilities. (I can't share images unfortunately, otherwise I would!)

My only complaint and it has nothing to do with the lens itself, just me as a human being. This lens is heavy, do get a strap if you plan on raising it, putting it down, and raising it again like I constantly had to do. You only make that mistake once and you will feel it the next day. Conveniently, this lens comes with its own bag, which is totally appreciated if you plan on switching lenses out and not wanting to run the risk of scratching it (as it is quite a big one). It also comes with a lens hood, again, totally appreciated and not only looks much more professional, but with stadium lights shining above, it's entirely useful and does a great job.
276371
I've used this lens for about a year now and I'm amazed at how good it is.  The original 100mm macro was amazingly sharp, but this lens is so sharp, that if you showed your photos to God, God would be cut.  The image stabilizer is a HUGE addition tot he original 100mm macro as well.  You get 3 stops of stabilization for up/down, side to side, and rotational vibration.  IS makes it possible to use this lens indoors without halogen flood lights or a tripod.  You still need as much light as you can get but previously normal indoor lighting handheld shots were impossible.  This lens is well made and has very smooth controls.  The focus range limit switches help shorten focus times on close up subject, though manual focus is still best for extreme close up photography.  The body is plastic unlike other L lenses, but so far that hasn't been a problem for me and the plastic body makes it light weight.
1415531
Easily one of the best lenses you can buy for any camera size format. I cannot wait to put this lens to work. Why have I waited this long to get my hands on this!!!!! Buy it.
4221650
This lens is amazing, it's an amazingly wide view, so useful for indoor group shots, or photo's of buildings without having to stand across the street.  I've shot thousands of pictures with mine already, no you can't have it, buy your own! :)
3401333
I love this lens. I am a hobbyist photographer. I feel like I have no business owning a lens this good. It's so impressive. It is just as sharp as Panasonic's legendary 20mm "pancake" prime lens. But this brings so much more. It brings a wider angle, of course (the equivalent of 10mm in full frame). It brings a physical F-Stop dial. And it brings a focus mode switch. The auto-focusing is fast and almost completely silent. Whether you shoot in color or black & white, the sharpness is surreal. This lens re-affirms that we M43 users don't need more megapixels. We just need the sharpest glass. This is a lens that will deliver amazing images for a lifetime.