Opteka makes an awesome Telephoto lens
341732
This lens definitely brings it in closer and with clarity.  The only drawback is the vignetting at normal focal point.  Loses the "tunnel" after 0.5x's zoom.  Other than that though GREAT!  Makes the pictures even better in my opinion! A must get!
4099894
Great lens for photography while traveling light. I'm able to shoot just anything using this lens. It goes from a wide 18mm to a great working telephoto at 250mm focal length. Excellent for street, news and hurry-up-and-shoot photography. The lens is sharp, beautiful, small and practical- delivers great photos. Comes with a very useful lens shade that truly works in removing glare and is reverse fitting for storage on the lens.
166651
I really like this lens. I was pleasantly surprised when I opened the box to find a soft carry bag, screwdriver, lens cloth, spacer ring, and printed instructions in addition to the lens and lens caps. It's surprisingly light weight as well.
The included lens hood causes black vignetting so I removed that and problem solved.  I also want to comment about the company support of this product. I (thought) I had an issue so I emailed them and they were very prompt and helpful. I actually got assisted by Mr Opteka himself. Wow!

The lens is a real bargain and the company (Opteka) reminds me of the kind of company and support that has become rare these days.
If you need a good quality fish eye lens I would not hesitate to buy this. It's nice to have one when you need those type shots.
1579813
First off, I'll say I'm an advanced enthusiast not into pixel peeping.  But this lens is great!  I got it primarily for some random nature walks and the 2 airshows I attend each year.  Optically, it's very sharp in the middle all focal lengths but definitely visibly falls off in the corners as I'm using it on a full-frame Canon 6D.  Not deal breaking but the outer edges are noticeably less sharp without pixel peeping.  Color rendition is very good, similar to my Canon L lenses, but probably just a bit less saturated/dull.  Focus speed is very good, I haven't missed any shots because of it yet.  If you use the focus distance limiting switches, it's even faster because it limits the focus hunting.  I haven't done any high speed tracking/panning with it yet, but that's not a super strength of the Canon 6D to begin with.  Build quality is excellent for the price.  Zoom and focus rings have good tension, no rough spots throughout the range.  All the parts fit together nicely, no play or wiggle while zooming.  The first part of the body (last 2" near the mount) is metal, the rest is thermally stable plastic as is pretty much the norm these days for non-professional grade lenses.  The tripod foot is also removeable and the lens includes a nice silicone ring to protect the foot mounts when removed.  It's also worth noting the lens comes with a nice padded, Sigma labeled bag with a strap to store/transport the lens.  This is a nice touch and saved me a few bucks since any third party lens case big enough to hold this size lens is at least $40.  Weight could definitely be an issue for some.  At 4.25lbs its my heaviest lens by far.  I use a Black Rapid RS-5 sling strap and it makes it relatively easy to carry, but a standard neck strap wouldn't work for anything more than a short stint.  For days at the airshow, I plan on using my monopod.  As a matter of habit and good practice I always put a B+W UV MRC filter on all my lenses. So just a warning that at 95mm, that size filter cost more than 10% of the lens' cost!  I waffled between this lens and the twice as expensive Sport model.  From the few online reviews available, the only real "cons" to this lens verses the sport is slightly lower optical clarity (but I'm not a pixel peeper as previously noted), slightly slower focus (could be an issue, but I'm no pro to begin with), and lack of the tank-like build quality and weather sealing.  So given these 3 cons, the only one that would really affect my personal use is build quality and I couldn't justify another thousand dollars for that.  The other obvious comparison for this lens is the similarly priced Tamron 150-600.  So the following is what swayed me to the Sigma: I'll say that I generally prefer Sigma to Tamron for third party lenses (though I do own Tamron's excellent new SP 15-30mm F2.8), I really like the look of Sigma's new Global Vision lens line (personal preference), the Sigma included a nice padded case, and the final one up over the Tamron is Sigma's USB dock.  And lastly, to cover the USB dock.  This lens has two "Custom" mode positions, and I made C1 a setting to prioritize speed in it's focus and OS and C2 a setting to prioritize accuracy in its focus and OS.

Update 11-16-2015: I still stand by this lens, it really is great.  Added some pics from the Great New England Airshow.  It was a cloudy, hazy, summer day and the lens still captured some pretty good color saturation.  Pics taken with my Canon 6D, all handheld, really shows off the len's OS.  Most pics were keepers (or at least good enough) given the fairly high-speed tracking.
623334
I read a lot about this lens before buying it, particularly worried about it being "slow" or "too big". Then read Ken Rockwell's (rave) review of it and some other positive comments from users here and decided to try it. I've been happy with my 35mm--sharp lens with beautiful bokeh and excellent low light performance (f1.4). But I missed a zoom (this one is manual--so nice. But it's a little stiff at first at 135mm so be sure to check that you're fully extending it in the beginning).

I love the range of this -- from wide (27mm equivalent) to telephoto (207mm equivalent). That is such a great range and this lens is actually -smaller- and lighter than the 18-55mm.

Plus the OIS is worth 5 stops--pretty incredible engineering feat there and it explains why this lens is not nearly as slow as I expected. The image quality is excellent and it really isn't that slow because (1) You can shoot up to ISO 1600, even sometimes to 3200 and still have a sharp image with acceptable noise and (2) the optical image stabilization system gives 5 stops (per Fuji, I have to take their word for it--but 5 stops, wow, that's very impressive.). You really can use the excellent OIS to handhold it at even 1/20, maybe, in good light, down to 1/8.

I like the buttons in the front of the lens that make it easy to turn OIS on or off and also, right next to it, make it easy to lock the exposure or have it able to be adjusted. The thread takes 67mm filters and you can put a couple on the front without worrying about vignetting. (I got an inexpensive Tiffen UV but not coated--about $12--works great). For sharpness, I did a test of our brick wall at full open  and stopped down, full wide FOV and zoomed in and all exceeded my expectations for sharpness, shutter speed needed and clarity. It was sharp in the corners even at full wide, although the sweet spot seems to be f8, particularly for landscapes. The bokeh is much better than I expected, too, when zoomed in. Portraits are excellent with this focal length.

Weather resistance adds even more versatility--it's a lens I wouldn't hesitate to take out in a rain, to a dusty carnival or to the beach. (I wouldn't subject it to a downpour or a duststorm, but its ability to stand up to "the elements" within reason really add to its travel possibilities. As Fuji says, this lens is dustproof, water resistant and has "weather resistant seals in 20 locations". Very durable.

This is a wonderful all-purpose lens and I keep it on the camera as my main lens about 90% of the time, maybe more. It often drops to $599 or so, so Fuji sales (which show up on Amazon, too) are worth waiting for.

Tip: If you want to see the information to show both aperture and shutter while you're shooting, don't use Auto ISO. Also, I've had good results with ISO bracketing as it will bracket lower than 200ISO if set at 200.  Another good bracket is Film Simulation which lets you choose 3 sims-- I like Provia, Velvia  plus B/W, to get an idea of dynamic range .
*******
(Note 6.19.15: re: Firmware. The latest firmware updates (1.01 came out Mar. 2015 for and another is due for the XF18-135--if used by the XT1 or XPro1-- by the end of June (XT10 already is updated).
323149
I absolutely love this lens. I bought the Nikon D600 body only after deciding not to buy it with the standard kit lens. I did lots of research and wanted a prime lens that I can mainly use for video work. I was surprised by the quality. Its pretty big and heavy and the results from this was amazing. See my test footage here: [...] Its incredibly sharp and produces beautiful bokeh. I like the de-clicked aperture that produces smooth focusing.

Also, I have to add that it survived a very high impact (accidental) drop test! I didn't have my bag zipped up properly and the camera, with lens attached, flew a few meters and landed lens first on cement. The fall was so loud I thought the glass would be shattered in peaces! Instead the body of my camera got hurt and the lens only had a few scratches on the body. So this is definitely a well built lens made to last!

Definitely recommended for someone who wants a good prime lens for video but it is very good for photography too.
1152374
I was totally blown away by the build quality of this lens, I have had some of Sigma's lower end lens and even those were still built really well.  These just are by far even better.  Optically this lens is definitely good.  This lens is heavy but that doesn't hinder me to take this lens out to go shooting.  I will be excited to try this on some air shows in the future!!
4146870
Hi purchased this lens a couple months ago specifically for a surf trip.  I needed a good telephoto lens for distance shots in bright to moderate light conditions and didn't want to spend a fortune as I typically do not have much need for a telephoto lens.  After doing a lot of research I decided on the Sigma 70-300 and was not disappointed.

I shoot with a Nikon D90 and all of my other lenses are Nikon so I was a little hesitant to go outside of my 'normal brand' but didn't want to spend thousands of dollars on a lens.  Most of the shooting I've done with this lens has been in bright light and I've found the AF response impressively fast, even at full zoom.  No issues to date.  Overall great purchase and amazing lens for the money.

[...]
895753
I have, so far, been impressed by the capabilities of this lens, in consideration of its cost. As most negative reviews state, it will not take the most stunning pictures. A $2,000 automatic Canon lens will far out perform the Opteka; but, for the hobbyist, or anyone looking for a low cost solution to long range photography, the Opteka lens performs very well. There is a moderate learning curve, as everything is manual. In other words, if you want automatic... automatic... and more automatic features, you'd have been just as well off with a point-and-shoot camera, rather than DSLR.
The lens is very sturdily built and is capable of amazing photos that aren't going to be enlarged to a ridiculous size. In spite of the many that state it is impossible to use without a sturdy tripod or ample light, this simply isn't the case. In bright conditions the lens, in capable hands, can easily capture moving targets that are far enough away; at night it is simple to capture any bright light source without, necessarily, requiring long exposures -- I have use it to photograph fireworks, from roughly three miles away from the display site, with good results. I have also used it for lunar photography without a tripod, but it does take a steady arm (or the ingenuity to sit down and prop the lens on your knees.) In terms of terrestrial photography, the results are quite good (depending on the lighting.) Unfortunately, the best you will be able to do without using an exposure longer than 1/250 second is ISO 400 on a cloudy day, so there is some graininess unless you use a tripod to capture a still target; however, it is still capable of photographing a license plate from 1/4 mile away (without the 2x extension, at the above mentioned settings) while still retaining the clarity to legibly read it. The lens is, essentially, a short range telescope; however, if you are expecting to use it for extremely distant subjects, I would opt to purchase a telescope and t-mount adapter instead.

On the downside, the lens is heavy and difficult to hold steady without the use of a tripod. It is also very difficult to aim, especially with the 2x extension attached; slight movements can cause you to completely lose your objective. Even a target as large as the moon can slip out of sight easily. If you are capable of focusing with both eyes (one through the viewfinder and lens, and one alongside the lens to the subject) it is much more manageable. The only problem I have actually had with the lens (other than its weight) is the tripod mount. It either uses different threading than what I have or was defective when I got it, as the quick release adapter on my tripod will not thread into the lens mount but will thread into my camera.

The short of it is: the lens is due a little more credit than it receives but, for the tight-budget hobbyist, it is worth every cent.
840178
I was very suprised at the clarity of this lens as I have tried numerous
lens in the past few months settled on a 100-400 canon l series[great lens]
This opteka 420-800 lens has good clarity and is great at macro even at
800 you can focus in very close, I really enjoy this lens.
4257734
I have had this lens for about a week now.  Summary review:  This lens is exquisite and heavy.
I upgraded from the Nikon 70-300 mm FX which I love. However, this lens (Nikon 200-500 mm) is utterly amazing.  It gives you the extra reach you have been wanting for your wildlife shots.  The contrast and clarity are phenomenal.  I hand shoot so the additional weight takes some getting used to but certainly not a problem.  Especially with +4.5 stops of VR!
I wanted to wait for Nikon to release a lens for the obsessed but semi/non-professional photographer.  Well Nikon delivered beyond my expectations.  The quality and value make this purchase an easy decision.  Simply stated: If you are interested in upgrading your tele., buy this lens.
I have included some photos from my first week with this lens.
1404643
I have always been a wide angle lens fan, so when I got a new Canon 5D body I decided to get this lens too.

I am very pleased with the brilliant optical performance, but don't think that it is a limited use lens because of the distortion inherent in a full frame fish-eye.

Using my image manipulation software (Paintshop Pro 8) I have corrected the distortion and obtained some stunning wide screen format landscapes which would have required 4 or 5 shots with a standard lens stitched together and the compromises that brings in matching brightness in the join areas.

After a couple of months use I have found  many more uses for this lens than I had imagined, I take it with me everywhere.

The ceiling of a mediaeval cathedral shot with the lens pointing vertically up is a revelation in detail and design which is hard to appreciate with any other lens.
605042
This big guy turned my 55-210 telephoto into a 350+ lens. It does perform quite good with mnimum light loss and little softening on the edges. It lowers depth of field so you can get nice defocussing effects. I got mine on ebay for 45 bucks so it was a bargain.
2195777
This lens is very sharp and is perfect for low light situations with a digital camera.  Slightly telephoto in the DX format, it also is great with a film camera or a D3.  Great product.
835615
The telephoto 12 x zoom lens is awesome!  I can really take descent pics of birds!  The stand is good for tabletop, but I ending up ordering separate remote for taking pics.  I haven't yet used the other lens yet.  Very easy to use, love it!
1144506
It's a very good lens for this price. It's not small and isn't light but it takes great photos. Excellent zoom and great depth of field. It also has a very quiet focus and reasonably fast. Love the autofocus and VR or Vibration Reduction. I am very happy with this lens.
854893
Hello everyone, ordered this product a couple of weeks back and i have been using this lens kit for a week for now and i should say that  these lens are the best. I would like pen down my review on a point wise for better clarity.

1) Firstly,the product build quality is super, the lens have an external casing which is far better than other manufacturers who use plastic material for casings. Metal really feels premium and gives good protection for inside lens

2) The telephoto lens is the one which made me fell in love with this product. It comes with 10x zoom and The clarity of the pictures clicked through telephoto lens are awesome. though there is a bit of distortion while zooming but, overall the photos clicked have got good detailing and crisp color contrast.

3) Fish eyes lens are good we cannot ask for much more for the price tag of this product. it comes with a 198 degree angle and i rarely used fish eye but it was good as i clicked few pics using it.

4) Macro lens is the second highlight of this product lineup. this lens has a 15x range and This helped me in clicking good pics and this lens never disappoints you requirements.

5)The package also include 0.63x wide lens attached with macro lens which is descent.

6) there is a bluetooth remote provided along with the lens for remotely clicking the pictures which is a nice addon for clicking when you are clicking pics with very close up angle.

7)There is  a Mini tripod and and a phone holder for shooting very close and stabilized pics with no distortion. the setup is small but is very useful for  closeup shoots.

8) All the lens are attached using a lens holder clip which has a Metal threading to screw the lens to the clip and connect it to phone.it is made of good plastic material and grips the lens well.

The package has a holder strap and a cleaning cloth and a instruction manual for setting up and basic instructions. over all i really loved the product personally. Worth every penny and a must buy for all the mobile photographers :) Thank you apexel for the beautiful product.