Đánh giá tamron 17-50mm f 2.8 xr di ii
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The Tamron AF 17-50mm F/2.8 SP XR Di II VC is an optically stabilized version of Tamron's 17-50/2.8 Di II, though the two lenses do not share exactly the same optical design. The "VC" version has one less XR glass element, but one more LD and one more aspherical element. "VC" or Vibration Compensation is Tamron's equivalent to Canon's IS (Image Stabilization) and Nikon's VR (Vibration Reduction). A group of movable optical elements within the lens is used to compensate for camera movement via feed back from gyroscopic sensors. .jpg) The "Di II" in the name indicates the Tamron 17-50/2.8 Di II VC is designed for use only on crop sensor cameras. The image circle of the lens is large enough to cover an APS-C sized sensor, but not a full frame (36mm x 24mm) sensor. Tamron Di II lenses can be physically mounted on full frame DSLR bodies (including full frame Canon EOS DSLRs), but severe vignetting of the image will result, i.e. the sides and corners of the image will be black as shown in the images below. .jpg) On an APS-C crop sensor DSLR, a 17-50mm zoom gives the same angle of view as a 26-75mm would on a full frame Nikon or Sony camera, or a 27-80mm lens would on a Canon EOS DSLR. This is the focal length range most used in landscape and travel photography, as well as being useful for portrait work The relatively fast f2.8 aperture togther with the optical stabilization means that the Tamron 17-50/2.8 Di II VC makes a good choice for hand held low light photography. Physical DescriptionThe Tamron 17-50/2.8 SP XR Di-II VC barrel finish is slightly textured and the markings are painted onto the barrel (not engraved). The barrel is made of a plastic material but the lens mount is metal. Focal length markings for 17mm, 24mm, 35mm and 50mm are printed on the barrel. There is a distance scale but no DOF markings, as is normal these days for zoom lenses. The rubberized zoom ring is about 3cm wide and is in the middlef the lens barrel. Approximately 90° of rotation are needed to go from 17mm to 50mm. The zoom ring can be locked with a small slide switch, but only at the 17mm position. Even unlocked there is no zoom creep, even when the lens is pointed straight up or down. Zooming is not internal and the lens extends from a length of about 9.5cm at 17mm to 12.5cm at the 50mm. VC (Vibration Control) is engaged via a small slide switch which is located next to the AF/MF switch on the side of the lens. There is only one mode which stabilizes both horizontal and vertical motion (pitch and yaw in technical terms). The front element of the lens does not rotate during either zooming or focusing (focusing is internal), which makes the use of a polarizing filter more convenient. A hood (petal style) which mounts on the lens using a bayonet fitting is supplied with the lens. The front of the lens is threaded for 72mm diameter filters and the lens cap is a "center squeeze" design which makes it easier to remove and replace with the lens hood mounted. 1. Autofocus is terribly inconsistent. It often misses focus, especially if light is at all low. This means shots are often very soft, undercutting the potential sharpness. I got a much higher keeper rate with the 18-135. Also, the autofocus is noisy - and when it is noisy and inaccurate, there is truly nothing to like about the autofocus. 2. There is a screw inside the lens which keeps getting loose and locks the zoom up. I've had to take the lens apart twice to reattach the screw, and I can feel it starting to catch a third time. Too much cost cutting with this lens. Because of its decent wide open performance, I plan to lock the whole lens to 17mm @ infinity focus, and use it only as an Astro lens for Milky way shots. Veteran Member Registered: July, 2008 Location: Detroit MI, USA Posts: 508 3 users found this helpful Review Date: June 18, 2021 Recommended | Price: $125.00 | Rating: 9 Pros: Sharp wide open, sharp corners Cons: No built in AF, No Weather sealing Sharpness: 10 Aberrations: 9 Bokeh: 9 Handling: 9 Value: 10 Camera Used: K-5 K20D Set this lens to f/4 or higher and it�s very sharp corner to corner throughout the focal range. Set to f2.8 it�s not much different just slightly lower sharpness in the corners but the corners are still good; again throughout the focal range. Something almost all Standard zooms struggle with, but not this lens. Chromatic aberration including purple fringing are low. I don�t have to deal with them in PP if I don�t want to. The CA/PF performance is at least as good as my Sigma 17-70mm f2.8-4.5 lens. This lens can replace a normal prime or two in your travel camera bag to free up space and lower weight a little. Say the 35mm f2.4, 50mm f1.8 or f1.7. With near equal light transmission and sharpness. The lens has nice rendering, With nice contrast and rich but neutral colors. It�s constant f2.8 aperture gives a bright viewfinder through its zoom range. It�s a major benefit in low light along with increased shutter speed and or lower ISO. Plus this lens is very good at f2.8, peaking around f5.8. It�s a Pro lens in terms of speed and optically. Build quality is above the kit, but below lens such as the Sigma 17-70mm f2.8-4.5. Perhaps it�s light weight unfairly makes it seem less well built than it is. After all light weight was a design goal of Tamron in this lens. Tamron uses 6 high-quality lens elements to reduce size and weight. Not many negatives, it doesn�t have a built-in auto-focus motor or shake reduction but that�s built into the Pentax body. The only real negative for me is the lack of weather sealing. However, this and the sigma 17-50mm f2.8 are the best standard third party walk around zooms (~17-50-18-55) out there IMO. The Tamron is equal to the Sigma optically according to most pro reviews, but the Tamron cost less and is notably smaller and lighter a plus in my aging opinion. ADENDUM I now own both the Sigma 17-50mm f/2.8 EX lens and the Tamron 17-50mm f/2.8. The above still holds as the Tamron is slightly better wide open. The Sigma is slightly better above f/2.8. The Sigma is heavy, but well built, it is the more reliable of the two according to user reviews. The Tamron inners are plastic, the Sigma metal. Little to choose from really IQ wise. Sigma offers in lens AF, Tamron Screw drive. Probably the biggest difference. Pentaxian Registered: November, 2014 Location: Washington, DC Posts: 1,745 1 user found this helpful Review Date: January 10, 2020 Recommended | Price: $275.00 | Rating: 8 Pros: Sharp; Budget; Decent Construction Cons: no weather sealing Sharpness: 8 Aberrations: 8 Bokeh: 8 Handling: 8 Value: 10 Camera Used: K-30 I got this lens to replace my DA WR 18-55 kit lens that came with my K-30. As kit lenses go, it was a great lens, but I ran up against the limitations of the slow and variable aperture, and wanted something sharper. And boy, does this deliver! If you need one well built, sharp, dependable, fast standard zoom lens, this is the one to get. Fantastic results. It doesn't have the same pop as some of the limited lenses, but it offers a lot. When I went back to my kit lens for a while, I really noticed the difference in quality. Another pro, it might be out of production but the new price is really low and comes with the longest warranty I've ever seen for a lens! Cons: I think the 50mm of this lens is a bit shorter than 50mm, comparing it to some other lenses I have. It may be more like a 45mm. Also, the "T-stop" of this lens may be closer to 3.2 than 2.8, and its a bit darker than comparable lenses. New Member Registered: April, 2015 Posts: 11 Review Date: July 5, 2019 Not Recommended | Price: $300.00 | Rating: 2 Pros: Sharpness Cons: Very slow AF; only useful for still objects. Sharpness: 9 Aberrations: 9 Bokeh: 9 Handling: 1 Value: 2 Camera Used: K-30 Very slow AF. New Member Registered: May, 2018 Posts: 10 Review Date: April 30, 2019 Recommended | Price: $169.00 | Rating: 6 Pros: Sharp, lightweight Cons: None yet Sharpness: 9 Aberrations: 9 Bokeh: 7 Handling: 10 Value: 10 Camera Used: Pentax K-5 1 Year Update: Took me a while to realize it, but I had a bad copy of this lens. I noticed a persistent front focusing issue with this lens, most noticeable when I was shooting portraits. Could not correct it in the settings of my K-5. Purchase price plus repair cost, I decided it wasn't worth keeping and went for the Sigma 17-50mm f2.8 DC EX HSM instead. Downgrading my rating to 6 due to Tamron's poor QC with this lens. If you get a good copy, it provides excellent value for the money. Picked this up from KEH (Excellent) for $169. Agree with other posters that its a little soft wide open, but not terribly so. Stopping down 1-2 stops sharpens things up quickly. I'm impressed by the ability of this lens on my K-5 to handle tricky lighting. I did not experience any hunting at all when getting this shot: Forum Member Registered: April, 2018 Location: Tartu Posts: 82 Review Date: December 20, 2018 Recommended | Price: $150.00 | Rating: 8 Pros: Sharpness - Close focus Cons: autofocus issues Sharpness: 9 Aberrations: 7 Bokeh: 6 Handling: 7 Value: 8 Camera Used: K50 and K3 Tamron 17-50mm F2.8 SP AF XR LD Aspherical IF Di II My thoughts after 7 months. Ergonomics and design
It's a great value lens that beats the much more expensive DA*16-50 F2.8 in sharpness. Just know that it might not provide as good of a look and lacks all the premium features of the DA* lens. If you can find it used for under 150$ it's a steal. Definitely recommended at that price. And whenever possible: test it out for AF issues before buying. Veteran Member Registered: November, 2014 Posts: 367 Review Date: December 14, 2018 Recommended | Price: $85.00 | Rating: 9 Pros: Very sharp, excellent IQ Cons: Build quality (loose screws) Sharpness: 10 Aberrations: 9 Bokeh: 9 Handling: 8 Value: 10 Camera Used: K3 & K-S2 I love this lens and can't believe I got it on Craigslist for only $70 last year and only needed to add a lens hood for $15 more. The image quality is top-notch but the build quality is shaky. The zoom mechanism was a little loose and would not register an accurate focal length on the camera when I first got it (but the images looked amazing). I dared to take it apart and found the loose screws and put it back together with a prayer that it would still work and I was not disappointed. Some other screws on the filter ring got loose that I had to tighten up as well. Even so it is certainly worth the money. I took this single frame 150 second Astro-trace photo of the Milky Way in July at Cherry Springs State Park in Pennsylvania. New Member Registered: November, 2016 Location: Alpes du Nord - FRANCE Posts: 1 Review Date: December 2, 2018 Recommended | Price: $150.00 | Rating: 9 Pros: Sharp, Constant F Cons: Sharpness: 9 Aberrations: 8 Bokeh: 8 Handling: 9 Value: 9 Camera Used: K5 and K3 Hi, This is a really good and cheap lens. This is my first review, for me picture can explain why i considering this lens. K3 + 17-50 @F4 ISO100 K5 + 17-50 @5.6 ISO400 Site Supporter Registered: January, 2017 Location: Sofia Posts: 861 Review Date: August 27, 2018 Recommended | Price: $250.00 | Rating: 10 Pros: Very sharp, light weight, fast focus Cons: none for me Sharpness: 9 Aberrations: 9 Bokeh: 8 Handling: 9 Value: 10 Camera Used: K500 Compared wit my kit lense DAL 18-55, this one is a level hiher. It is as sharp as the kit on 2.8 and much faster ofcours. From 4.0 it is extreamly sharp and dhe 27 sm. focusing distanse makes it almost macro lense. I didn't believed it untill I tried it. My pease is very stabel with no comlains on handling. It is the closest to the universal lens I can imagine and is perfect walkarownd lense for me. I'm very happy to have it. Veteran Member Registered: December, 2013 Posts: 796 Review Date: July 7, 2018 Recommended | Price: $400.00 | Rating: 8 Pros: Sharp, flare resistant Cons: Focus accuracy, cheap build, bad quality control Sharpness: 10 Aberrations: 9 Bokeh: 7 Handling: 7 Value: 9 Camera Used: K-30 This lens is sharp. My copy was extremly sharp from F3.2 for a zoom. Altough the official pentax and tamron service couldn't set the focus calibration correctly for my lens. (I sent back the first copy with the same fault.) This lens feeles cheap even after handling a DAL kit lens. The hood is soft and the touch of the focus ring is bad. However the lens optically is very good. When I changed to a DA*16-50, I missed the sharpness and flare resistance of the tamron. Altough the DA* has some magic and a more plesent creamy bokeh. Here are some images: Junior Member Registered: January, 2013 Location: Texas Posts: 32 Review Date: November 28, 2017 Recommended | Price: None indicated | Rating: 9 Pros: Light weight, Price, Sharpness Cons: Manual focusing, no aperture ring Sharpness: 9 Aberrations: 9 Bokeh: 9 Handling: 8 Value: 10 Camera Used: Pentax K30, K70, KP Good built quality for the price. At 17mm, very sharp, but a little bit too much distortion and vignetting. At 50mm, less sharp. Very light lens for a 17-50/2.8. Excellent value. In terms of image quality, very close to Pentax DA Limited 20-40/2.8-4.0, and slightly better than Sigma 17-70/2.8-4.0 C, The focusing ring is not very good (too light, short course), as most autofocus lenses. Forum Member Registered: November, 2013 Location: Queensland, Australia Posts: 87 Review Date: June 19, 2017 Recommended | Price: $200.00 | Rating: 9 Pros: Image quality, Contrast, Cons: Low light AF, Sharpness: 9 Aberrations: 8 Bokeh: 7 Handling: 8 Value: 9 Camera Used: KS1 K200D I've had this lens for about three years now, and was my first upgrade from the kit lens. Comments have been made regarding the build quality but I've felt it has been robust enough for my needs over those years. The image quality, contrast and AF are fantastic in good light. Thankfully in Australia we have that in plentiful supply. Low light will let you down at times, and the overall results can be a bit patchy. When it's good it's good... etc. I've just purchased the DA 15mm HD limited, so it will be interesting to see if the results from that lens exceed the Tamron. It is fantastic value for money, especially when compared to the Pentax/Sigma comparable zoom lenses. |
