Đánh giá sony sel 18 200mm năm 2024
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APS-C only, 35mm equivalent, 27-300mm. Will work on full frame where you'll get full coverage from 100-200mm at infinity focus, but APS-C size capt. will auto crop image on A900. Depth of field and focus scales? Distance scale only Minimum focus, image plane to subject 18" (457mm) Minimum focus, end of lens barrel to subject 8.3" (211mm) Hard stop at infinity focus? No Length changes when focusing? No Focus ring turns in AF? Yes Filter size 62mm Filter ring rotates? No Distance encoder? Yes Max magnification 0.27x Min. F/stop F/22-40 Sony teleconverter compatible? No Length changes when zooming? Yes Dimensions W x L (my measurements) 2.9" x 3.4" 73mm x 86mm Maximum extended length (my measurements) 5.95" (151mm) Weight bare (my scale) 14.1oz (401g) 15.1oz (428g) with caps The Sony A700 was used for this review. For a better understanding of my review methods and terminology, go here. The Sony 18-200mm is a rebadged Konica Minolta lens that came out in 2005. It's about the same size as the newer Sony 18-250mm, 16-105mm and CZ 16-80mm. The Sony 18-200mm looks to be made mostly of plastic, and has a plastic mount, surprising for a $500 lens. It has no zoom lock, but it could use one, like the 18-250mm. It says made in Japan. Build quality is about average. It has a rubber ribbed grip area around the zoom and focus rings, typical for Sony lenses. The lens has the focus distance marks (white and orange numbers) with the standard FT/M. The focal length index marks are at 18mm, 35mm, 50mm, 70mm, 100mm, 135mm, and 200mm. The EXIF data matches the marks on the lens. This lens is for APS-C size sensor cameras, and is not designed for film or full frame cameras, but will work in crop mode using full frame cameras. This lens focuses a little slow at all focal lengths, but it's accurate with the A700. It likes to focus in "steps" mostly at the long end, just like the 18-250mm. That's normal with this type of lens. The manual focus ring is not the best, it only takes about 1/6 of a turn from close to infinity focus, plus it makes the usual gear noise which isn't so pleasant. Sharp focus is tough as the ring has a little play in it so it's easy to overshoot your in-focus area. In everyday use, set to AF, it's pretty good though. Aperture/focal length guide for the Sony 18-200mm F/3.5-6.3 This lens has one set of overlapping numbers, at 50mm you can get F/4, or F/4.5, depending on tiny movements of the zoom ring, this is quite common. This lens stops down the aperture a little quicker along the zoom than the Sony 18-250mm. Look below for guide. Maximum aperture F/3.5 F/4 F/4.5 F/5 F/5.6 F/6.3 Range 18mm-22mm 24mm - 30mm 35mm - 50mm 50mm - 60mm 70mm - 105mm 120mm - 200mm Flare and ghosting. The lens glass is close to the end of the barrel. Flare and ghosting are a problem from 18mm to around 35mm. Look for some green and red ghosts with the sun in the frame, see small image below. With the sun centered, no problems other than a vertical sun spike, at the wide end, just visible in the sample below. This lens is a little better, but not much, at controlling flare and ghosting than the 18-250mm. The lens comes with a petal type hood, which is pretty small. It works ok, but doesn't eliminate all problems. Use your hand for best control of flare/ghosting when the sun is outside the frame. I don't normally use hoods, but you may as well use it if you have it, it will help some. On a side note; if you lose the hood to this lens, it'll cost you $25 to replace it. The hoods from the 18-200mm, and 18-250mm are not interchangeable; go figure! This lens is multi-coated and has the mild green/amber/magenta look and it appears to be about the same as other similar lenses from Sony. Filter size. 62mm. Other Sony lenses using this size are: 70-300mm G, CZ 16-80mm, 16-105mm, 24-105mm and the 18-250mm. Filter use. There's no additional vignetting using regular filters on this lens. Coma. Light at 18mm-50mm, with a wide open aperture, one stop down and it's mostly gone. Color. Looks the same as other Sony lenses. Color fringing control is about average to below average on this type of lens, It's mostly noticeable at the end of the zoom, just like the 18-250mm lens. Stopping it down makes it worse at 200mm because of soft shots at F/6.3, where color fringing can hide itself, stopped down to F/11 where things are pretty sharp it's more noticeable, and magenta is the dominate color. Check the corner shots below. You'll have to look hard to see it on wide angle shots, but it is noticeable at 100%, here look for red and green. In the centers towards the end of the zoom, you'll find some color fringing, and stopping down does get rid of it, but only in the centers. See crops farther down. All this stuff doesn't really come into play unless you're shooting telephoto and/or looking at your pictures at huge sizes. Distortion below. Barrel and pincushion distortion. The distortion at 18mm is fairly strong, but less than the 18-250mm. At 24mm it's flat, from then on pincushion sets in and stays for the duration. I would describe the distortion on this lens as strong at 18mm, and moderate pincushion as you extend the zoom. The overall distortion produced by this lens is less severe than on the Sony 18-250mm. Lens Bokeh. The Sony 18-200mm F/3.5-6.3 doesn't have a very appealing bokeh in my opinion, it's the same as the 18-250mm, a little harsh or "busy" looking. See sample crops below. light fall-off (directly below) looks moderate at 18mm and F/3.5, then clears up a stop down or so. It's light by 50mm, then mild to nothing past 70mm. This lens performed nearly identical to the Sony 18-250mm in this category. 18mm @ F/3.5 18mm @ F/5.6 200mm @ F/6.3 200mm @ F/8 Random shots below. 18mm @ F/3.5 light fall-off 18mm @ F/5.6 ghosting 18mm @ F/3.5 bokeh 18mm @ F/5.6 bokeh 200mm @ F/6.3 bokeh 200mm @ F/8 bokeh 18mm @ F/3.5 coma 18mm @ F/5 coma The top left shot shows light fall-off, and how it's hardly noticeable in real shots, as opposed to the grey cards. On the right is some ghosting, and typical in what you'll get when you shoot with the sun in the image. Sometimes a busy background will hide this stuff. Bokeh, middle crops, looks a little harsh, but typical for a super-zoom, and also no better, or worse than the 18-70mm kit lens. The bottom crops show coma, which is light, but goes all the way up around 50mm using the maximum aperture for that length, also see some light streaks, I'm not sure what the cause of this is. It's not very common. This stuff doesn't show up in regular sized pictures, I've deliberately tried to get the worst shot to show you how the lens performs under various conditions. Corner softness, 18mm. See cropped images below. 18mm @ F/3.5 18mm @ F/5.6 18mm @ F/8 18mm @ F/11 200mm @ F/6.3 200mm @ F/11 The corners from 18mm-50mm are very soft. I takes about two stops down (F/8) to sharpen up. This lens is much softer in the corners at F/3.5 than the Sony 18-250mm. The corners at the long end are really not much different from the centers, soft at F/6.3, a little sharper at F/8, and the sharpest at F/11. Check out the color fringing in the shots directly above. In normal telephoto shots, it's hard to tell the difference in sharpness between F/8 and F/11 in the centers or corners. If you like taking pictures of test charts and stamps, you definitely need to stop down to F/11-16 at full zoom. Center samples next. 18mm centers below F/3.5 F/5.6 F/8 The 18mm wide end is a little dull at F/3.5, but sharpens up nicely at F/5.6, F/8 is the same, then diffraction softens the F/11 image (not shown). I think the 18-250mm is a little sharper at F/3.5, 18mm. 200mm centers below 200mm centers below F/6.3 F/8 F/11 Examples of center CA below. 200mm @ F/6.3 200mm @ F/11 In the top crops, you can see improvements in sharpness by stopping down the lens to F/11, just make sure you watch your shutter speeds. This is a 300 meter shot, where atmospheric conditions can wreak havoc on fine details. The F/6.3 image is a little soft at 200mm, at F/8 it's better, with F/11 as the sharpest aperture. There isn't a huge difference, but it's worth pointing out. The second block of crops are from the center too, and show how the CA disappears as you stop down, but only in the central region, it stays the same or gets worse along the periphery. See the Sony 18-250mm for examples. Below, you'll see the difference in coverage between the 18-200mm lens at 200mm, and the 18-250mm lens at 250mm. Check out the macro shot. Below, check out the sample and click the picture to see a 100% cropped portion of the full image, (315kb). The sample shot was taken with the Sony A700 12.2MP camera. The subject is a standard US stamp, 1"x 3/4" or 25.4mm x 19mm. Also, note the macro shot was taken as close to the subject as focusing allowed; In this case, 9.9" or 251mm, measured from the front of the lens barrel to the subject. This lens has the same macro issue as the Sony 18-250mm, it isn't very sharp until you stop down to F/10-11, the shot below was taken at F/14, though it looks pretty much the same at F/11. It has a maximum magnification of 0.27x, slightly smaller than the 0.29x 18-250mm, but they look the same to me. Still, a decent looking shot of a small item with a lot of detail. This lens does a decent job for the price. With a "kit" purchase you can get the Sony 18-200mm F/3.5-6.3 for around $300, and that's a good deal. If you purchase it at full retail, $548, it's not such a good deal. Read more below. |
