Sigma 18-50mm f/2.8 EX DC 技術規格

Sigma 18-50mm f/2.8 EX DC 技術規格

可用的接環	Canon EF, Nikon F, Pentax K, Sony / Minolta A, FourThirds, Sigma
應用	人像, 風景, 建築物
類目	標準變焦
倍增器	1.5×
穩定器	否
焦距	18 - 50 mm (2.8× 變焦)
鏡片組	13 群組含有15 元素
視角	35毫米: 不適用 數碼: 69.3-27.9°
葉片數目	7
最大光圈	廣角: f/2.8 遠攝: f/2.8
最小光圈	廣角: f/22 遠攝: 不適用
最短焦距	28 cm
放大	0.2×
濾鏡大小	67 mm
大小	∅ 74.1 × 84.1 mm
重量	445 g
記錄
自動對焦速度	不適用
自動對焦聲音
內置對焦	是
內置變焦	不適用
固定前鏡頭	是
接駁類型	鐵
天氣密封	不適用
插入濾鏡	否
超聲波自動對焦	否
APS-C大小的圈	是
低散光度鏡頭元素	是
硬機殼	不適用
軟機殼	包含
遮光罩	包含 可印刷的遮光罩
三腳架接合器	不適用
已停產	是

Sigma 18-50mm f/2.8 EX DC 評語

Other reviews

• Sigma 18-50mm f/2.8 EX DC 評語 在www.ephotozine.com (英文)
• Sigma 18-50mm f/2.8 EX DC 評語 在www.the-digital-picture.com (英文)
• Sigma 18-50mm f/2.8 EX DC 評語 在www.shuttertalk.com (英文)
• Sigma 18-50mm f/2.8 EX DC 評語 在www.the-digital-picture.com (英文)
• Sigma 18-50mm f/2.8 EX DC 評語 在pixinfo.com (匈牙利文)

Sigma 18-50mm f/2.8 EX DC 用者評語

亞瑪遜內最有用的用家評語

I like it on my 20D - compares well with Canon 28mm/2.8

24 November 2004

I have a Canon 20D, and I have had these lenses:


Canon 50mm/1.8 (my reference standard for the best lens performance I can reasonably expect)

Canon 28-135 IS

Canon 28/2.8

Sigma 18-50/2.8


Canon 18-55 EFS


I have found that the Sigma 18-50/2.8 is the lens I keep on my camera most of the time. It has very good color, contrast, sharpness, saturation, and low distortion and aberration. By contrast to the 18-55 kit lens that came with my camera, the Sigma is in a whole different class. I would compare it favorably with my Canon 28/2.8 prime lens. I have never used a prime lens wider than 28mm, so I can't speak as to what the distortion is like at 18mm compared to a prime, but in general I am very pleased with the Sigma.

I find it has better dynamic range than the Canon 28-135 did; I can get better textures and ranges of intensity.

For the highest quality, I always go to my Canon 50/1.8, but in walking around and general shooting, I use the Sigma.

I was interested in the Canon 17-40L, but from what I have seen there is not a lot of difference in the quality from that lens and this one. Perhaps a little less distortion, but nothing you would notice unless you are taking pictures of brick walls.

Fantastic Lens!

27 December 2004

This lens is soooo sharp. I returned a sigma 17-35mm EX DG HSM. The 17-35mm was a good lens with superb build. The 18-50mm f/2.8 is a great lens with good build. HSM would be nice and so would full time manual focus. Having said that. The focus is fast but not silent. However it is not loud either. And the auto focus is sharp, so I haven't had to use manual focus. It is so light that at first you think hey is the build cheap? No it isn't! It works well on my EOS 20D. If Sigma could make this lens 17-85mm they would sell a million of them. There is a lock for zoom creep but I never use it because there is no zoom creep. Oh yes the color and contrast are also great.

Product description QUITE WRONG, and lens has been REPLACED with a better one - don't buy it!

12 January 2007

This is a terrific lens, but Sigma has now re-released it as an 18-50mm F/2.8 EX DC Lens with MACRO capability (can focus down to 8", and 1:3 magnification), for very little additional cost, making this version of the lens essentially obsolete.

Furthermore, the other reviewer is correct that Cameta's (or Amazon's) description is quite misleading. This is NOT the Macro version of this lens. It will NOT give you 1:1 magnification (nor will the Macro version, for that matter, so I'm at a loss as to how such an unrealistic claim found its way into the ad copy!)

To locate the NEW, improved version of this lens, search on:

Sigma 18-50mm 2.8 MACRO CANON (one is also made for Nikons)

Pretty good lens

19 September 2006

I bought this lens with my Canon Rebel XTi. The default lens that came with the camera was very bad (EF-S 18-55mm f3.5-5.6). I don't recommend it to anyone, it is really a waste of the camera's capabilities, and the pictures you get may not be as good as that from a point and shoot camera.

I am very happy with the Sigma lens. I love the f2.8 feature as it makes indoor pictures (w/o flash) much better. The pictures are pretty sharp in general (especially around the focus point). Beware that taking pictures at f2.8 can be tricky, i.e. while the image center is in focus, the edges and other more distant points may be not be (try increasing the f number if there is sufficient light).

There are three lenses in the market with comparable price & performance: Sigma 18-50mm f/2.8 EX DC, Tamron SP AF17-50mm F/2.8 Di II LD and Canon EF-S 17-85mm f/4-5.6 IS USM. Sigma is the cheapest and the other two are a bit more expensive.

I've just compared my Sigma with a friend's Canon today. The picture qualities were almost identical. Canon was a bit sharper due to Image Stabilization, but f2.8 in Sigma compansates for that. Overall, the picture qualities were very very similar. Canon has a slightly wider range of zoom, but I don't know if it worthy of $150 price delta. The barrel distortion at 18mm is noticeable with both cameras.

The reviews I read online indicate that Tamron and Sigma lenses are pretty similar, although the reviews for Tamron are a bit better. I haven't tested the Tamron yet.

I haven't had any focusing issues with the Sigma. It takes a while to get used to auto-focus function in Rebel cameras and perfect focusing is not 100% guaranteed. But that's true for any lens. You just need to learn how to do it.

I am aware of only one lens which is considerably better than the Sigma: Canon EF-S 17-55mm f/2.8 IS USM. That lens really rocks. Its colors are more saturated and it is sharper due to IS. However, it is _very_ expensive. If you cannot afford it, one of the three lenses above can be your choice. Sigma offers the best value among three, and it has pretty good performance.

F2.8 is GREAT!

17 September 2005

Image stabilization is the new hotness in lens design, but being an old-fashioned sort, I went on a search for a lens with a wide maximum aperture instead. Sure, IS and VR give you the ability to hand-hold week long exposures, but what if your subject is moving? Amazing what a difference that extra stop can make when you need to capture action in low light. Plus, the AF system works better, and the viewfinder is brighter.

Cost, however, is what drove me to this lens. Due to financial constraints, I could afford no more than $500 for a lens for my 300D, which knocked the Canon L-series glass out of contention. After looking at the Tokina and Sigma 28-70 F2.8 lenses, I discovered this lens was in the pipeline and held out for it.

It's not a replacement for the Canon L-Series lenses. That's the bad news. The good news is that this is possibly the PERFECT advanced amatuer lens. Good optical quality, though a little soft at F2.8. Focuses quickly, and "wanders" less than other EF-mount lenses I own (18-55mm EF-S kit lens; low-end Sigma 28-90). The wide aperture allows for auto focusing in what feel like "no light" situations.

Strengths:
Quick focus, little focus "wander", good build quality, included sunshade and case, relatively light weight and small size

Weaknesses:
Works only with APS-C image sensors, a little soft at F2.8

Very good, yes, but DON'T BUY IT! now replaced by another Sigma with MACRO!

12 January 2007

This is indeed a very good lens with strong reviews. It provides an affordable alternative to the unaffordable over-one-grand Nikkor 17-55 f/2.8.

Why would you want to get an f/2.8 constant aperture lens like this when you could get a "superzoom" lense that goes from 18-200mm?

Because a constant minimum aperture 2.8 lens like this one allows you to shoot nonblurry photos in low light conditions, AND because it allows you to create the most artistically blurred-out backgrounds in closeup photos. Zooms with variable minimum apertures higher than 2.8 cannot do either of those well. That's what you'll miss out on if you buy the Nikon 18-200mm VR lens, for exampe. VR (Vibration Reduction) can eliminate the effect of a wobbly hand on the camera, but it CAN'T help you "freeze the action" of the scene right in front of you. Only a higher ISO (noisy, grainy, poor resolution) or a wider aperture (confusingly, the low numbers like 2.8, 2.0, 1.8, 1.4 are the wider apertures) can solve the blurry action problem.

BUT DON'T BUY IT. Why not? Because this autumn (Fall '06) Sigma introduced a version of this same lens that is slightly updated, and, importantly, allows you to get closer to a flower or other object (8"!) and magnify such objects up to 1:3 resolution, which begins to approach the Macro range (people define Macro differently, of course, but for many flower lovers 1:3 magnification is sufficient).

The 1:3 magnification option adds a world of beauty to your walk-around picture-taking.

To have a wide-angle lens, a portrait lens, AND a macro lens all on one lens? Terrific. And the price for the MACRO version is only a few dollars more.

HOW TO TELL THE DIFFERENCE: The names of the lenses are basically identical except the newer version includes the word MACRO somewhere in its title. If the product name doesn't say MACRO, it's the older lens.

Nice Lens!

8 June 2006

I use this lens on my Nikon D70. It's great. Before I bought it, I thought I should get a lens with better range, example, the Nikon 18-200mm lens. My friend had told me about this one, so I decided to buy it for the heckuvit. I was glad I did. The range isn't a big deal now, but the only problem is--umm--uhh--I can't really think of any problems I've had with this lens, besides the fact that I all of my lenses, I use this one the most, and I paid all that money for the other lenses! Trust me, it's great.

A very good lens

6 October 2006

I took a look a this lens almost as a fluke -- I wanted something that gave me quick speed at 2.8 but had more range than than the prime standard 50/1.8...and I was so pleased with the lens I have used it quite a bit more than I thought I would. The quality of the photos is excellent, good colors, good contrast. The lens is relatively light (less than a pound) so it "feels good" on the body. Compare this lens to the Tamron 17-50/2.8 They are virtually identical. This is a supurb replacement for your standard kit lens.

Good all around lens

11 January 2007

This is a good lens to have in the bag for an amateur photographer like myself. The lens is relatively fast with a constant 2.8 aperture throughout the zoom. The lens is sharp at f-stops 4 and above and workes quite well even wide open. I use it on a Nikon D50. Focusing is fast. Overall I am quite happy with the purchase. Check out pictures at

[.....]

A very good lens indeed

2 April 2007

I bought this lens because my REAL Nikon film lenses did not perform well with my new digital SLR. To make the whole story short, I had invested $1400 in a digital SLR in hopes that I could use my Nikon lenses. But to my surprise...those lenses didn't perform well at all. So I took a chance on this Sigma lens (after reading the reviews of course). It was the least expensive lens in my bag but it gave the best result. The images were very sharp with good colors and detail. Again, thanks to those who took the time to write the earlier reviews. They had helped me tremendously.

General purpose and low light option

26 November 2006

I recently made the jump into my first DSLR, a Pentax K100D. However, like most "kit" lenses, the provided 18-55 seemed to be average at best (based on reviews, etc), so I opted to get the body only, then pick and choose some lenses.

I went with a Pentax 10-17mm fisheye-superwide zoom, and a Sigma 70-300 telephoto zoom. I like the extreme perspectives those lenses can provide.
However, for the bread-and-butter mid-range lens, I decided to pay a bit more (OK, three times the price of the kit lens, and more than either other lens) for the extra f-stops and reputed sharpness of this lens.

The lens is a little larger and heavier than similar-range slower lenses due to the extra glass. It has a zoom-lock at 18mm which prevents the zoom from creeping out if you are the type to let your camera hang on the strap - I'm not. I support the camera under the lens in my left hand.

As with my other Sigma lens, they recommend putting it in manual-focus mode when adding or removing the nice included lens hood to prevent damage to the focusing system. Perhaps that's a good habit to get into, though remember to slide it back into AF (if that's your style) or you'll be fumbling to focus your first shot :-)

For some reason, Sigma is not consistent with their zoom rotation direction - it's counterclockwise wide-to-zoom on the 18-50, but clockwise on the 70-300.

I'm happy with the results. Now (a year later), it is discontinued (replaced by a macro version), and sells for $100 less. As they say, a picture is worth a thousands words, so I'm posting some photos in the Amazon collection.

Better Than The Pentax Kit Lens

9 August 2007

Allow me to start off by stating that I am an "old school film" photographer. When I mean old school I am talking about Nikon F and Nikkormat cameras. I also acquired some Pentax screwmount bodies and lenses back in the late sixties and early seventies. The lenses were made of metal and glass. They were sturdy, uncomplicated and still considered sharp to this day. Today we have too much plastic IMHO. Not to mention motors!
I joined the digital revolution awhile back. I'm still waiting for affordable Nikon bodies that meter with the AI lenses. The D200 is just too much for me to consider.
Recently, I purchased an affordable Pentax K100D with the kit lens. After doing my own testing at various apertures and focal length settings, I came to the conclusion that it was OK for the money but I wanted something sharper.
So I bought this Sigma lens. This Sigma lens is way better and more costly but definitely worth it. Wide open it blows the kit lens away. Its wider (f:2.8) than the kit lens (f:3.5). In darkened interiors that little extra one half F stop will come in handy and be sharper as a bonus! Also, its F:2.8 over the entire focal range. This lens is a worthy investment and you will notice the sharpness.

Pros:

Sharp
Larger minimum F stop
responsive

Cons:

Costs more than the Pentax kit lens
Uses larger filters (62mm as opposed to 52mm)
Weighs more (I don't mind though)

I feel that the Pros outweigh the Cons. Go for it. You won't be sorry.

Great lens!

28 March 2007

This is a great lens for the money. It works perfect on the K10. The sevice was fast and I look forward to buying more products.

fast lens

23 May 2007

Product performed as expected. Excellent low light performance and very fast lens. At extreme wide angle (18mm) you may need to rotate lens petal shape lens cover to keep shadow out or just take lens cover off. Built solid (great build quality) with metal mount and excellent finish. The lens is sharpe throughout the zoom range. The EX version is impressive with a good solid feel to the lens. This lens is on my camera 80% of the time. Vendor shipped product in safe and expedited manner. I will do business with them again.

Solid lens

4 April 2007

Had this lens 2 weeks now, major and huge difference from the kit lens. No vignetting and very fast at 2.8 throughout. I'll update if i find problems later.

And by the way! CHEEEEEEEEEEEEEEEP and affordable :)

Sigma 18-50mm f/2.8 EX DC 圖例

Canon EOS 300D + Sigma 18-50mm f/2.8 EX DC

Sigma 18-50mm f/2.8 EX DC 配件

遮光罩Sigma 18-50mm f/2.8 EX DC

• 72mm multi-coated UV filters Canon Ef 50mm 1.4 Sigma 2.70 USD
• Sigma AF Zoom Super 100 Battery (Equivalent) 3.95 USD
• Sigma AF Zoom Super 28 Battery (Equivalent) 3.95 USD
• Sigma DL2025 Battery (Equivalent) 3.95 USD
• Sigma AF Zoom Super 70 Battery (Equivalent) 3.95 USD
• Sigma 35AF Zoom Battery (Equivalent) 3.95 USD
• Sigma 28AF Zoom Battery (Equivalent) 3.95 USD
• Sigma EX DG 55mm Multi-Coated UV Filter 4.95 USD
• 3.70V, 1230mAh, Li-ion, Replacement Digital Camera Battery for SAMSUNG SLB-1237 & SIGMA BP-31 & EPSON B31B173003CU B32B818242 EPALB2 EU-94 5.46 USD
• Sigma Accessory Front Lens Cap - 52mm 6.35 USD

67 mm 濾鏡

67 mm 極化濾鏡

• 67mm 3 FILTER KIT POLARIZER + UV + FDL LOOK NEW 11.48 USD
• Nikon D40X - 67mm High Resolution 3-piece Filter Set (UV, Fluorescent, Polarizer) - (not Nikon Brand) 13.15 USD
• Sony Cybershot DSC-R1 - 67mm High Resolution 3-piece Filter Set (UV, Fluorescent, Polarizer) - (not sony brand) 13.15 USD
• Panasonic Lumix DMC-L10 - 67mm High Resolution 3-piece Filter Set (UV, Fluorescent, Polarizer) - (Not panasonic brand) 13.15 USD
• Samsung GX-20 - 67mm High Resolution 3-piece Filter Set (UV, Fluorescent, Polarizer) - (not Samsung brand 14.95 USD
• Tiffen 67mm Neutral Density 0.9 Filter 0.00
• 3 PC. FILTER KIT 67mm 67 Polarizer CPL UV FD FOR CANON NIKON LENS 16.99 USD
• 67MM 3PC. FILTER KIT Cir Polarizer CPL UV FLD ++ FOR Canon Lens 16.99 USD
• Hoya 67mm Circular Blue Polarizer Glass Filter 24.17 USD
• Zeikos 67mm 3-Piece (UV Haze / CPL Circular Polarizing / FLD Fluorescent Correction) Digital Multi-Coated Glass Filter Kit with Case 19.95 USD

67 mm 紫外線濾鏡

• MERKURY 67MM UV FILTER 2.55 USD
• Tiffen 67mm UV Protection Filter 0.00
• HOYA 67mm UV Haze Protection Filter 0.00
• SunPak PicturesPlus 67mm UV Haze & Protection Filter for Digital & Analog Photography
• Opteka 67mm High Definition Professional UV Protective Filter 7.95 USD
• 67mm Multi Coated UV Filter 67 mm UV Lens Protector 7.95 USD
• Opteka 67mm High Definition² UV (0) Ultra Violet Haze Multi-Coated Glass Filter 7.95 USD
• HOYA 67mm Skylight 1B Warming Filter 7.99 USD
• Sunpak DF-7036-UV 67mm Coated Ultra-Violet Filter 9.95 USD
• 67MM PLD+UV+FLD FILTERS - NIKON D50 D70 D70S D100 D200 11.38 USD

67 mm 日光濾鏡

• Sunpak 67mm Skylight 1A Warming Enhancing Filter 5.99 USD
• HOYA 67mm Skylight 1B Warming Filter 7.99 USD
• Tiffen 72MM 1A Skylight Filter for Camera Lens 0.00
• Quantaray - 67mm Skylight 1A Filter 19.99 USD
• Quantaray - 67mm Skylight 1A Multi-Coated Filter 24.99 USD
• Hoya 67mm Skylight Multi Coated Glass Filter 29.99 USD
• Tiffen 67mm Skylight Wide Angle Thin Glass Filter 34.68 USD
• Heliopan 67mm Skylight Filter (KR 1.5) #706715 51.25 USD
• B + W 67mm Skylight 1A Coated Multi Coated (2C) Glass Filter (KR1.5) 54.95 USD
• B+W B & W 67mm EW Filter for Wide-Angle Lenses KR-1.5 Skylight 1A Filter For Color Film

67 mm 鏡頭蓋

• Sunpak Platinum Plus 67mm Camera Lens Cap 1.99 USD
• Snap on Lens Cap 67mm 2.78 USD
• Center pinch 67mm snap-on lens cap with keeper 3.95 USD
• Bower 67mm Plastic Lens Cap 4.95 USD
• Mennon Pro Center Pinch 67mm Snap-On Lens Cap with Leash 4.95 USD
• OP/Tech 11671 67MM FAST CAP 5.04 USD
• Plastic Snap-In 67mm Lens Cap 5.89 USD
• HAKUBA USA INC KA-LC67 67mm LENS CAP 5.99 USD
• OP/Tech 07671 67MM FILTER CAP 6.76 USD
• Olympus LC-67 67mm Lens Cap for 14-54mm & 50-200mm Olympus Lenses 6.85 USD