Product Description

10-20mm F4-5.6 EX DC lens allows enjoyment of super wide-angle photography and it is a very powerful tool for indoor shooting and landscape photography with APS-C size image sensors of digital SLR cameras.Wide angle of view (102.4 ? at 10mm and 63.8 ? at 20mm) offers the photographer greater freedom of expression. Three SLD glass elements are employed for effective compensation of color aberration, which is a common problem with super-wide angle lenses. One piece of glass mold and two hybrid aspherical lenses, offer excellent correction for distortion, as well as all types of aberration.This lens is equipped with an inner focusing system and also offer full time manual focusing. It has a minimum focusing distance of 24cm (9.4") at all focal lengths. The non-rotating lens barrel perfectly suits the petal shaped lens hood. A circular polarizing filter can also be used conveniently.

Product Details

• Brand: Sigma
• Model: B000ELC666
• Released on: 2006-05-04
• Dimensions: 3.30" h x 3.30" w x 3.20" l, 1.04 pounds

Features

• 10-20mm ultra-wide angle lens designed for Pentax and Samsung digital SLR cameras
• 3 special low dispersion (SLD) glass elements to compensate for color aberration
• Multilayer lens coating reduces flare and ghost; 9.4-inch close focusing distance
• Measures 3.3 inches in diameter and 3.2 inches long; weighs 16.4 ounces

Amazon.com Product Description

Designed exclusively for Pentax digital SLR cameras, the ultra-wide-angle 10-20mm offers a view from 102.4 to 63.8 degrees, making it ideal for landscape photography and other vast applications. The lens is distinguished by its three special low dispersion (SLD) glass elements, which effectively compensate for color aberration, and its aspherical lenses, which provide maximum correction for distortion and various aberrations. As a result, the lens produces an extremely high image quality throughout the entire zoom range. Other details include a minimum focusing distance of 9.4 inches at all focal lengths and an integral petal-type hood to block out extraneous light.

Lens Elements and Coating
The new multilayer lens coating and lens design reduce flare and ghost--a common problem with digital cameras--while also creating an optimal color balance throughout the entire zoom range. At the same time, the lens offers three SLD glass elements that effectively compensate for color aberration, along with a piece of glass mold and two hybrid aspherical lenses that offer excellent correction for distortion and all types of aberration.

Inner Focusing System
The lens incorporates an internal focusing system that eliminates front lens rotation, letting you use a petal-type hood to protect from additional glare.

Best Consumer Lens
The Sigma 10-20mm lens is so respected that it was named the best consumer lens in Europe (2006) by the Technical Image Press Association (TIPA), a collection of 31 publications from 12 countries. According to TIPA, the 10-20mm lens offers a versatile range of wide-angle focal lengths, a good optical performance, and a budget price, making it an excellent investment for owners of DSLRs with APS-C format sensors. Its sharpness remains constant throughout the zoom range, and its compact size makes it an ideal companion for shooting travel, landscapes, or architectural subjects.

• Lens construction: 14 elements in 10 groups
• Angle of view: 102.4 to 63.8 degrees
• Number of diaphragm blades: 6
• Minimum aperture: f/22
• Minimum focusing distance: 9.4 inches
• Maximum magnification: 1:6.7
• Filter size: 77mm
• Dimensions: 3.3 inches in diameter and 3.2 inches long
• Weight: 16.4 ounces

Manufacturer Description

Designed exclusively for Minolta and Sony digital SLR cameras, the ultra-wide-angle 10-20mm offers a view from 102.4 to 63.8 degrees, making it ideal for landscape photography and other vast applications. The lens is distinguished by its three special low dispersion (SLD) glass elements, which effectively compensate for color aberration, and its aspherical lenses, which provide maximum correction for distortion and various aberrations. As a result, the lens produces an extremely high image quality throughout the entire zoom range. Other details include a minimum focusing distance of 9.4 inches at all focal lengths and an integral petal-type hood to block out extraneous light.

Lens Elements and Coating
The new multilayer lens coating and lens design reduce flare and ghost--a common problem with digital cameras--while also creating an optimal color balance throughout the entire zoom range. At the same time, the lens offers three SLD glass elements that effectively compensate for color aberration, along with a piece of glass mold and two hybrid aspherical lenses that offer excellent correction for distortion and all types of aberration.

Inner Focusing System
The lens incorporates an internal focusing system that eliminates front lens rotation, letting you use a petal-type hood to protect from additional glare.

Best Consumer Lens
The Sigma 10-20mm lens is so respected that it was named the best consumer lens in Europe (2006) by the Technical Image Press Association (TIPA), a collection of 31 publications from 12 countries. According to TIPA, the 10-20mm lens offers a versatile range of wide-angle focal lengths, a good optical performance, and a budget price, making it an excellent investment for owners of DSLRs with APS-C format sensors. Its sharpness remains constant throughout the zoom range, and its compact size makes it an ideal companion for shooting travel, landscapes, or architectural subjects.

• Lens construction: 14 elements in 10 groups
• Angle of view: 102.4 to 63.8 degrees
• Number of diaphragm blades: 6
• Minimum aperture: f/22
• Minimum focusing distance: 9.4 inches
• Maximum magnification: 1:6.7
• Filter size: 77mm
• Dimensions: 3.3 inches in diameter and 3.2 inches long
• Weight: 16.4 ounces

Customer Reviews

Very good lens. If you can focus it correctly.
My first impression when I received a package with this lens was "Wow!".
This lens is very well built and it comes with a dedicated case.
There was an extended warranty from Sigma included with the lens in addition to the standard one. If I remember well, it was 4 or 5 years in total. Very good, Sigma!
The Sigma 10-20 mm f/4-5.6 EX lens for Pentax mount looks different from the picture on Amazon. It does not have the window for scale, instead the last one is just painted on the barrel. And certainly it is not HSM, but a "screwdriver" type.
It mounts and locks on my *istDs and K10D easily. Surprisingly, I still can rotate the lens in the mount (in locked position) to a small but noticeable degree. It seems that the lock mechanism on this lens has "extended" tolerance and/or the mount coupling lens-body is not tight enough. This is a bit annoying. The zoom barrel is stiff in operation, so it happens to me to push it a bit harder and so turn the lens in the mount.
Now a few words about the optical quality of this lens.
I read many reports stating that their copy of the lens was good, as well as the ones stating the opposite.
Although my copy of this lens is not as sharp as my prime lenses (which was expected), it is good. But there is one "BUT".
My lens is sharp provided it is focused correctly. This is something difficult to achieve in certain situations and especially at wider angles. With this lens the AF tends to lock elsewhere, but not on the subject. And often there is no consistency - even if I focus several times on the same subject which is 3 meters away, the AF may lock anywhere from 1 m to infinity.
I am not sure if this is the lens or the camera AF system which causes such behaviour. In most cases I just set the distance manually and rely on the DOF.

Could be 1 Star, Could be 5 Stars! Read More:
I am rating this lens with only three stars because I am reviewing two lenses. Here is why:

When I received my lens I later realized that I did not receive the extended three year warranty card that comes with the USA versions of the lens. Instead of just sending me the extended warranty card Amazon shipped me a whole new lens. Now while I was reading reviews prior to ordering this lens I had seen many reviews where the reviewer either loved this lens or they hated it. After a while I could see why...

Some of the lenses that are being shipped are sharp all the way around while some are not sharp at all. Many claimed it was sharper at F:8 than F:4 while others said theirs was never sharp at all. Some complained about distortion and or dull or over saturated colors. I finally found a reviewer who had the opportunity to try 3-4 different lenses. They found that there seemed to be a lack of quality control all around when it came to this specific lens. Having a few days of both lenses I decided to compare them out for myself. I am glad I did.

I put my camera in the front yard on a tripod and shot numerous sets of three for each lens at 10mm, 14mm, and 20mm. The results were surprising. The original lens I had been sent first was a clear winner. The trees and anything else around the picture were sharp, The replacement lens was anything but sharp. The colors on lens two were more vibrant than lens one but one can fix that with software where a blurred image is not really fixable.

I shot numerous sets with both lenses and a few different F settings and the results remained the same. The replacement lens was the one being returned. Lucky for me the Sigma extended warranty cards have nothing on them, you enter the serial numbers yourself so I kept the card and returned the replacement lens.

I have included two photos to the gallery for this lens so you can see what I found. In the end my first lens would have received a 5 star rating because they really are excellent lenses if you can get a good copy. The replacement copy would have received a 1 star rating. Luckily I had the chance to compare the two copies side by side or I may have never known just how bad lens number two really was.

If your lens has problems like lens number two you have a poor copy of the lens, return it. Sadly from all of the reviews I have read it seems that maybe 20% of the lenses are not good copies. Many just think poor sharpness is just a general lens limitation when chances are it is just a poor copy they received.

Bottom line!

1. Get the lens out and shoot some shots, If it is not sharp around the edges return it for another copy.

2. If you do not get your extended warranty card you may have gotten a gray market lens. Return it.

Upon talking to a Sigma rep I was told they have no way to verify whether the lens is USA or Gray market (international) by the serial number, if you do not have the extended warranty card you will not get the warranty extension so buyer beware. The card is a card stock type black and red folded warranty card that specifically states that it is the extended warranty card. Don't let any dealer tell you that it has the extended warranty without it being in your hands. Sigma currently has no registration on their website. The rep told me to keep the card in a safe place and then in the event that I need service I will send it and a copy of the original sales receipt in with the lens for service.

All that being said I can tell you that this is a wonderful lens if you need a super wide angle lens and you get a good copy. They are not the fastest lenses around but for the money you cannot beat it.

Take a look at the pictures I included for the lens and hopefully they will help you determine if you were lucky on the Sigma draw and give you an idea of what you need to check for.

Amazing lens!
I've had this lens for four months now. I wanted to get a good feel for it before I signed off on it.

I have been completely impressed with this lens on my K10D. At 10mm, the lens is super wide, but doesn't distort images like a fisheye lens would, unless you get very close to your subject. At 20mm, there is very little noticeable distortion.

This lens is extremely sharp when shooting with a medium aperture, much sharper than I would have hoped for.

Overall, this is an incredible lens, and well worth the money.