A: Canon was established in 1934, using the brand name is "Kwanon", is the Buddhist goddess of mercy ("Goddess of Mercy") name. Later became the "Canon", the reason is still a bit unclear. Previously, I said it was Latin, the meaning is precise. However, a user told me that it is actually a Greek word, meaning: (1) an accepted principles or guidelines; (2) a judge of the criteria or standards; (3) a principle, guidelines, standards or norms content. It may be a simple name-based market research. .
EOS is an optical system (Electro Optical System), which indicates that the body and lens coupling between e..
A: Now most of the Canon EF lenses by USM (ultrasonic motor) to focus. There are a small portion of the lens, and many have discontinued the use of AFD (arc motors) and MM (Micro motor) systems. .
What is the difference between them? traditional motor, such as AFD/MM, the electromagnetic force into rotation, USM is based on the ultrasonic vibration of energy, the use of transmission wave to drive.
There are two different types of USM:. .
Ring-USM: ring USM is the fastest USM. Usually it is accompanied with full time manual (FTM).
Micro-USM: Micro USM is used in less expensive Canon lenses, like a 75-300II ,28-80II-IV ,35-80 and so on. .
Canon 50/1. .4USM is the only one to have FTM functionality of micro-motor lens!..
USM has the following features: Quiet! Only you can hear the sound focusing lens group moving. Ring USM focusing system than the traditional lot quicker. Micro USM a bit slower than the ring USM, but, and AFD / MM comparison is still quite fast. Low power consumption. Temperature in the limit no problem. AFD / MM: big noise. Unless it is within the focusing lens, or very slow. AFD a little faster than the MM. High energy consumption. .
Q: what is a full time manual (FTM)?.
A: full-time manual (FTM = Full-Time Manual) allows you do not have to consider whether it is in the AF state can be manual focus! This allows you to do a little fine-tune or completely change the location of the focal plane. Obviously, this feature only in "single auto-focus" of the AF mode makes sense. .
Q: Canon's parts are there compatibility problems?.
A: In the EOS system, there is no compatibility issues. Canon's EF lens of any one can be in any EOS camera body to use without any loss of functionality, quality or anything. When you want to use an old camera in the new camera body, or conversely, it is Nikon users often encounter problems, but you will not lose any exposure procedures, or auto focus. The only "limit" is 300/4L IS lens and 2x Teleconverters (600 / 8) with time, older EOS body IS feature turned off.However, this combination is 600/8, its optical quality is too low, so it is only a theoretical problem?.
Q: Does the third party products have compatibility issues? . .
A: the old shima and tuli lens (93 years or older) in the newer EOS fuselage (EOS 5/A2 (E), 50/EOS Elan II (E), EOS 500n/RebelG) will result in a software error which led them to temporarily shut down (reflectors are still in the position sign up, the battery starts blinking). This does not cause damage to the fuselage, but you cannot use this lens, except from the manufacturer to upgrade the software. However, they could not afford to upgrade shima all lens, so it is best to leave those tempting second-hand shima lens. Dragon seems to be the only body with the EOS lenses with no problems of third-party vendors - at least until now. Now, all these compatibility issues - temporary - can be resolved, but without any guarantee that will not happen again, because the Canon never provided any body - lens communication of information. For example, the recent discovery of third-party vendors and the new Nikon F5 lens problem. If this can happen, then for the next generation of EOS body the same thing can happen. So before buying third-party products must think twice. .
Many lens:.
When the half-press the shutter aperture when the barbaric operation. .
Most lens:.
After the shutter release the camera stopped working. .
Reflective plate location, stopping on the lift.
Battery symbol flashing. .
Most lens:.
After the shutter release the camera stopped working. .
Reflective plate location, stopping on the lift.
Battery symbol flashing. .
In addition to the HSM version of the lens out of a lot of lens:.
After the shutter release the camera stopped working. .
Reflectors in lift position, the battery symbol flashes.
(?, Except EOS 50 before the lens). .
Aperture control issues.
20 / 1. .8 EX. .
24/1。.8 EX。.
28 / 1. .8 EX. .
180/3。.5 APO macro HSM 。.
Q: Canon Teleconverters How? . .
A: there are now two additional Canon from the mirror (related information 1, relevant information 2): they belong to the best of the market from the mirror, but can only be used in more than Canon 135mm L lens focusing, as well as the Canon 70-200/2. .8L and 100-400/4.5-5. .6L IS.
In the third vendor side, many good cheap alternative to the program: Sigma of Sigma EX Teleconverter can match the Canon lens and fixed focus, focal lengths over 135mm L lens, and Canon 70-200/2. .8 L & 100-400/4. .5-5. .6 L IS. Teleconverter and Kenko's can match any lens, because it does not pre-set lens protruding. But the Kenko Pro series is more than 200mm telephoto lens optimized for use in the standard zoom head is meaningless.Some lens coupled with third-party vendors of distance lenses do not follow the above mentioned law (compatibility problems?).
Do not expect to use a 2x Teleconverter miracle after what, whether you use Canon EF2. .0 X or Kenko AF PRO 2x. Only some very high-quality lenses, such as 300 / 2. .8 (IS) or 400 / 2. .8 II (IS) can try to get good performance. .
A: it is difficult to measure the use of additional distance of lens lens performance, because it is too dependent on the design of the lens, of course, also depend on increasing the quality of the pitch. However, there are still some rules to follow: maximum aperture of the lens, combined with increasing distance to mirror the quality will be better potential. Added additional distance of lens aperture should not exceed f/5. .6 — otherwise the lens performance tend to be lower than expectations, despite some very high-quality focusing lenses can be considered "available" quality.
In general Canon EF 1. .4 X give the lens by one point (with a very good lens can be a good one. .4 Times the focal length lens), but the EF 2x lens will reduce the two points (with a very good lens will become a only twice the normal focal length lens). For most of the lens design, the use of double Teleconverter usually is too high, so like in the 75-300 USM lens below-average use Teleconverter usually meaningless, and Canon The Teleconverter is also possible from the machinery used in this type of lens on the. .
Until now, the third-party manufacturers of performance from the mirror. However Shima (APO increase from mirror) and Kenko (AF 300 Pro) is a very good choice, basically and original Canon lenses the same level. So, if you want to save the economy could consider both. It should be noted that future compatibility remains a problem. The following table are based on Canon's Lens Work in MTF curve. I do not know the reliability of these data, some form looks a bit strange - but better than nothing, right? Colors that approximate the same focal length. .
(Maximum * ** **, following A previous/B indicates A = maximum aperture readings, B = f/8 is the number of degrees, how to comment on the bottom of this page to see the stars).
Other EF135/2L USM with 2xTC poor performance when the corner. . EF3. .5 180 / 3. .5 L USM very good performance EF200 / 2. .8 L USM. .
- 。.
EF70-200 / 2. .8 L USM @ 200mm Canon recommends using center focus. The zoom lens, the very good performance EF100-300 / 5. .6 L @ 300mm Cannot take EF extenders! Can reach 300mm a cheap option EF300/4L USM a bit lower than expected EF400 / 5. .6 L USM with 1. .4 XTC still good EF100-400 / 4. .5-5. .6L USM IS @ 400mm incredible performance, though it is not possible in the real world.
A: If, after installing the Teleconverter aperture is less than 5. .6, Except EOS-3, 1V, all EOS AF cameras will be closed. But this is not always the case. Teleconverters third vendor is not the correct aperture to the body pass, such as an f / 4 lens with a 2X lens on the camera, but it seems an f / 4 lens, and Canon's double mirror will pass the correct f / 8 to the body. So what will happen? . .
You really can f/8 around the aperture AF, but don't expect the focus to be accurate and stable. In sunny day, may 6 at f/2. aperture down., to be able to get a better result. In addition, there is a viable method of making small aperture lens and Canon's increasing margin endoscope also AF. Canon's increasing distance lens has three additional contacts, with a thin plastic film cover them. This may be in areas such as 500/4.5 + 1. .4xTC or 180/3. .5 + 2xTC such combinations for auto focus. Do not try to "low quality" slow motion, such as 75-300mm zoom, use the Teleconverter. The pictures are very poor! I use my Canon 100-300/5. .6 L + Kenko 2xTC been tested, the result is still far less than acceptable level (at least in terms of slides and posters, this is the case). .
A:L refers to the "Luxury" (luxury), symbolizes the professional quality of the lens. And consumer level cameras compared with ground aspherical, UD, SUD or CaF2 lenses, these are excellent optical quality lenses. Often the quality of the lens is also excellent for many.
A: color for the first telescope is a common problem, these special lenses are used to solve this problem. CaF2 (a synthetic calcium fluorite crystal) lenses provide excellent correction for almost UD glass (Extra-low Dispersion glass) twice, but it is a lot more expensive, only used in very few shots inside. UD lenses are widely used in the L level of the telescope head inside. SUD (Super-UD) better than the UD, but still smaller than CaF2, up to now only used in 400 / 5. .6 L lens.According to the magazine's test, you can say for sure that even ordinary UD glass than third manufacturers of APO lens is good.
A: Canon's use of "multi-layer vapor deposition coating technology makes reflectivity reduced to 0. .2 ~ 0. .3%", Instead of the lens coating reflectivity is 10% of incident light 4, the coating look like very effective. However, other competitors (M *, N *, P *) in this regard seems to have better performance in that test also showed that this magazine. Once users have reported that Pentax lenses (with the SMC coating) is more resistant than the Canon lens glare. Canon seems to find the problem, because most lenses are more equipped with the new lens aperture glare.For example, 17-35L lens than its predecessor, the ability of the anti-glare many, may be the anti-glare aperture. The above discussion it seems a bit far-fetched, since there is no strict test data.
You can combine a number of close-up lap to get a higher magnification, but sooner or later you will not auto focus, or manual focus also becomes very difficult, because the viewfinder was too dark inside. There is also a relatively inexpensive option is to Vivitar AF 100 / 3. .5 Macro lens. .
A third, more often than the manufacturer's lenses Canon original lens cheap, in most cases, the low price means that relatively low optical and mechanical quality, especially machinery. However, we often can find some very value of the lens, for instance, tuli 28-80/2. .8 ATX Pro, it is worth considering in place of the Canon brand. However, in addition to quality, there is also a very important reason to choose Canon that compatibility. You may now third manufacturers lenses can existing Canon EOS camera, but it is still possible in the future on the camera. This has happened many times! The reason is to buy third-party vendors have neither the lens mount of the patent, and no lens and body of the communication protocol, they do it through reverse engineering, they analyzed the signals between the body and lens to simulate the key part (see compatibility with third-party product issues). Obviously, this method can not be without problems. The earliest defects in EOS 5/A2E body, the Sigma lens because of the frequent operation issued aperture strange sound. After the upgrade the camera firmware on all normal.Whereas the EOS Elan II 50/released, shima and tuli is wrong, the lens will lock the entire camera. Similarly, a few months the camera firmware is upgraded. This upgrade is often paid by the user, and some old lens also can not be upgraded. Three years later, shima company rise again until 1998, EOS 3 release. Once more, most third manufacturer's lenses, even the latest model (for example, shima-EX lens), in the new machine is not working properly, the serious mistake of aperture, light point also appear such as cannot auto focus problems . Until now, these problems have been resolved. But these problems will continue to gradually offset the difference between the original edge, and those who can not upgrade the camera can only be thrown into the trash the. Of course, we can blame Canon causing these problems, but on the other hand, all the Canon lenses, including the old lenses and new machines can never match the good. We may have to face this compatibility issue, until the third party is willing to spend big money buying proprietary lens mount. .
A: floating af institutions heralds close-up focusing performance relatively better. Magazine test often only measuring lens at infinity focus setting, however, in actual shooting distance of the performance is likely to become very bad, especially on large aperture wide angle lens and lens. The following list of EOS bayonet lenses autofocus with floating bodies (this does not include macro lenses, they are usually with floating autofocus mechanism):.
Canon EF 14 / 2. .8 L USM. .
Canon EF 20/2. .8 USM.
Canon EF 24 / 2. .8. .
Canon EF 50/1. .0 L USM.
Canon EF 85 / 1. .2 L USM. .
Canon TS-E 24/3.5 L.
Canon TS-E 45 / 2. .8. .
Canon EF 17-35/2. .8 L..
Canon EF 100-400/4. .5-5. .6 L USM IS. .
Tuli AF 17/3. .5 AT-X Pro.
Tokina AF 20-35/2. .8 AT-X Pro. .
Tuli AF 80-200/2. .8 AT-X Pro.
Sigma AF 24 / 2. .8 Macro. .
A: the highlight of glare ratio is a key issue. Generally there are three ways to reduce flare and ghosting:.
The first two methods are widely used, but the third method is not standard. The following table lists have "glare aperture," Structure of the lens. This is not a guarantee of the lens flare will certainly small, but shows the efforts of manufacturers to reduce the glare. .
Canon EF 20/2. .8 USM.
Canon EF 28 / 1. .8 USM. .
Canon EF 28/2. .8.
Canon EF 35 / 2. .
Canon EF 50/1. .0 L USM.
Canon EF 135 / 2 L USM. .
Canon EF 180/3.5 L macro USM.
Canon EF 300 / 2. .8 L USM. .
Canon EF 17-35/2.2 L USM (*).
Canon EF 20-35/3. .5-4. .5 USM. .
Canon EF 24-85/3.4. .5 .5-USM (*).
Canon EF 28-70/2. .8 L USM (*). .
Canon EF 28-80/3.5-5. IV .6 (USM) (*).
Canon EF 70-200/2. .8 L USM. .
Canon EF 75-300/4-5. II .6 (USM).
Canon EF 80-200/4. .5-5. .6 (USM) II. .
Canon EF 100-300/4.5-5. .6 USM.
Tokina AF 80-400/4. .5-5. .6 AT-X. .
Tuli AF 35-300/4.5-6. .7.
Tokina AF 80-200/2. .8 AT-X Pro (not sure). .
Image stabilization (IS):.
A: Simply put: the camera's vibration is the main cause of fuzzy photos. Especially for telephoto lenses and low light conditions even more so. To solve this problem is often a matter of lenses with a larger aperture (and more expensive) or a higher sensitivity of the film. Canon on this issue, a new solution is stable image itself. Camera's movement by two gyro sensors detect, detection is the angular velocity of vibration. This information is used to control the movement of a group of lens, making the optical axis offset, and thus to correct the movement. The result is significantly improved the situation of the holding of the limit.For example, for a 300 mm lens for 1/60 seconds may be successful, without need to 1/250-1/300 sec, about 2 retaining aperture. And traditional handheld shooting results compared to the same sharp and clear. Use the IS and will not lead to a decline in quality (of course, use a tripod will be sharper)! obviously this technology or the scope of application of the suits of Aperture upgrade just the "simulation". Aperture f/5. .6 of lens aperture IS still f/5. .6 lens. You may like to use f/2. 8 lens, as access to very shallow depth of field, which can only use the large aperture. .
You get these stalls and let your Aperture is just shooting speed can be increased slowly, for example, you can at the 300/5.1/.6 90 seconds, but the real 300/2. .8 only 1/350s! This is only valid for the rest, the body movement a..
On the other hand, IS a lot of extreme conditions can be, but 300 / 2. .8 L on. .
A: there are some rumors on the tripod used when using a tripod IS function has a reaction, IS will damage the picture quality. This is obviously nonsense. You can see in the description: "when inside the camera on the tripod, please do not put the IS function to the ' I '. Doing so may cause incorrect operation IS. Use the camera on the tripod when close IS. " Moreover, this description is only for the following efficient several scenes: EF 28-135/3.5.5-USM IS .6.
EF 75-300/4-5. .6 USM IS. .
EF 300/4 USM L IS 。.
EF 100-400/4. .5-5. .6 USM L IS. .
The following is Chuck Westphal (Canon USA) explains: "the device IS used for calibration of vibration. When the system detects the vibration is less than the capacity, the use IS likely to increase in the ' photos ' unexpected. Therefore you should in this case IS close to the lens group IS locked in position. When it IS turned on, the lens group IS locked due to no, you may be driving coil. When there is not enough movement was detected when the IS system, camera movement may be an electronic feedback on the impact of this feedback is that we are all familiar with like radio noise feedback circuit in the ring. The result is that it makes the camera when the tripod on the IS lens group is moved. Unless the IS function is turned off, IS lens group is locked. . ".
Canon has just launched the next generation IS a professional camera. These lenses are "tripod detection" feature, which means that the lens IS in use on a tripod is not a problem, and IS also corrects camera mirror movements caused by vibration. Until now, that's the lens including 2. EF 300/L IS USM .8.
EF 400 / 2. .8 USM L IS. .
EF 500/4 USM L IS 。.
EF 600 / 4 USM L IS. .
A: this is the series which IS the only section that contains a wide-angle zoom lens. From optical quality, and popular EF24-85/3. .5 .5-4. and the EF28-105/3. .5 .5-4. counterparts. Performance IS better than those of non-a lens is said to be the same, even a little better. But more than 28-70/2. .8L difference (it is also not surprising). Journal of testing has shown that the full open aperture kinda soft, especially in the corners, but slightly smaller aperture is very good. Open IS, Canon claims that can be obtained at the end of the "28mm" 1. 5 block aperture, (minimum 1 / 10 seconds), the 135mm end of "captured" by 2 block (minimum 1 / 30 seconds). Lens with a ring USM motor only has full-time manual function. Like the 75-300 IS, only one IS model. Overall, only the best Canon lens may be a mirror to go travel the world scene. .
A: this lens optical performance and it turned out that only 75-300mm similar to 300mm-very soft, 75mm to 200mm is also good. It is very attractive because he can 75mm paragraph 1/15 sec can also be a clear image. 1/60 sec 300mm segment. If your own skill, can also be used to shoot at a lower speed, course, 1/15 sec at 300mm segment is limit, unless you're a robot. Only the mechanical characteristics of the lens than the non-IS version of the lens is slightly better, but still only with a micro-USM motor, not full-time manual function. The front lens rotates, while the auto focus speed and 100-300/4. .5-5. .6 USM lens is relatively slow in comparison. Overall, this is a pretty good shot, if you mainly shoot smaller imprints. .
A: the consumer-level compared to the 75-300IS this lens is completely different! picture quality and mechanical quality deserves the "L" level camera. Testing has shown that it is not better than the old 300/4L poor. This IS the lens might be a little more prone to glare, because there are more lenses (13 to 8). In addition to the standard IS mode, it also offers a new "flat" mode, shake this mode IS only for calibration of vibration in the vertical direction. This is sport sports photography is very useful, you might encounter a scenario where you need to track the subject in the horizontal direction. In general, IS function can be used with the Canon Teleconverter, which before the body for EOS50 not necessarily the old body (including EOS5, 1N) can only cope with one. .4 X TC to achieve IS function. .
A: it's only early product shots, have reflected its performance at 400-not perfect. However, these early product BUG has been fixed, formal testing has shown that it is indeed an excellent zoom head. "Chasseur d'Images", here is a trusted source of information, they pointed out that this lens is that they tested the focal length of lens in one of the best. Test chart indicates that the entire focal length segments even if performance of the full aperture is also very good. Canon's Lens Work book of the MTF curve that it's outstanding performance, especially in the 400mm end. With 1. .4 Times Teleconverter also very good, although a 560 / 8 lens and not much use. It can also meet 2 times Teleconverter, making it a 800/11. .2 Monster, probably no one wants. The same as 300/4L IS, the lens only provides two IS modes - a normal mode, you can correct the image fuzzy in both directions, the other is the "pan" mode, only the vertical vibration correction .Just like ordinary IS functionality, you can "get" Aperture 2 block, so that you can use at 400-1/125 s (or fewer) handheld shooting. Shortcomings, this lens is a push-pull zoom. You can quickly change the focal length, but more than rotation zoom determines the location of the hard to find. The focal length can be locked to prevent the zoom slider. Mechanical characteristics, this lens is standard L lens standards.
Notes:. .
IS-mode 1 = normal mode, the object still shots.
IS-Mode 2 = square wave pattern, the level of shooting moving objects. .
Tripod camera can detect = in use IS on a tripod.
A: If you do not consider these differences in the lens focal length range, that number is almost the same as the performance of the lens. Their performance better than most of the third optical lens manufacturers is good, but better than EF 28-70/2. .8 L difference, of course, also can not compare the price. Overall, the wide-angle end of geometric distortion are more serious, Wang Yuanduan image a little soft, has fast USM motor, and full-time manual function. Filter size is completely different (58mm (28-105), 67mm (24-85), 72mm (28-135)).28-105 and 28-135 IS for inclined to portrait photography is more appropriate, whereas 24-85 for inclined to photography people better. 28-135 IS obviously more practical because it has a feature that IS already explained above.
Other options: In the Canon's products, there is an old EF 28-70/3. .5-4. .5 MK II is a similar shot once considered one of the best. Since 92 years have already discontinued, so it is hard to find. However, with this lens, using polarized light microscopy will be very painful, because the former group in the zoom and focus lens, when will turn, and will mirror barrel income inside. No USM motor, but the optical quality than the 24-85mm and 28-105mm are much better. .
If you want more money, then the tuli AF 28-70/2.2. .8AT-X .6-Pro II is expected to be a very good choice, very good optical quality and mechanical structures, and L level comparable to the lens. Shima AF 28-70/2. .8 EX from optical weight that is also very attractive, however and tuli than slightly worse. (Please note that third-party manufacturers, product compatibility problems).
A: These three lenses are very good optical performance, resolution and contrast reduction in the aperture to f / 5. .6 The following time is excellent, but when fully open aperture a bit soft, which is a common problem with large aperture lenses. 50 / 1. .8 MK I and MK II optical structure is the same, but from the color balance a little bit different point of view, MK II neutral pH and some of the old version of warmer. However, two shots from the mechanical structure of view there is a huge difference! Old MK I is a metal mount lens, and construction firm, and the new MK II is very loose.There used to be the center of the MK II lens (uneven sharpness). 50/1. .4 this one is clearly faster than 50/1. MK II structure also .8 to strong. In addition, it is also equipped with micro-USM motor, as well as a full time manual (FTM) feature. Generally speaking, the lens should be the best choice, but the contrast a bit on the expensive (about 50/1. four times the price of .8). Preferably from the secondary market to find the old 50/1. .8 MK I, but this is a very difficult thing.
A: comparison of this two lens question about EOS newsgroups and mailing lists of the most frequently asked questions. Although the optical structure is different from the performance of two lenses are very similar: it looks not very good, but it is for the vast majority of 75/100-300mm zoom lens is the same. From the mechanical quality, the two cameras is somewhat different. 100-300/4. .5-5. .6 USM has ring USM motor, full-time manual and non-rotating front lens group. The 75-300/4-5. .6 USM is slower micro motor wearer, former group will rotate. In General, 100-300 seems better, unless hand tight.
Canon is how to treat these two lenses:. .
Other options: Canon (Canon or third vendor) shots only a performance is quite good and affordable starting from 100-300 mm zoom lens, 100-300/5. .6L (not expensive 100-400L). Obviously you must provide this extra to pay more for quality and price, but you will find in the secondary market is still very expensive, (than a new 100-300/4.5-5. .6USM your little bit). It does not have a USM motor and push-pull zoom, unfortunately when focusing the lens rotates in front of the group. Mechanical quality of the lens will not lens than those of consumer good, but not bad. Because CaFo-and a UD lens, image contrast and sharpness are quite good. .
Mention of third-party manufacturer's lenses, often frustrating. Tenglong 70-300/4-5. .6 LD like low-level market a choice. It is Nikon's Nikkor 70-300/4-5. .6 ED have the same optical design, "LD" lenses to improve the performance of the telephoto side, making it better than non-l Canon head better. "Shima AF 70-300/4.5-5. .6 APO macro super" (Oh, this is what the name AH) sounds quite interesting, but very few users there is a good evaluation.
(Please note that third-party vendor product compatibility issues). .
A: the following table summarizes the common Canon EF bayonet lens of 400mm views and test results.
Old L head comparison:. .
A: these two camera intercomparison process more difficult, as the new head of the wide angle end begin from 17mm the following recommendations are restricted to 20-35 zoom end. Two shots of the overall performance is very good, but the old lens resolution may be a little a little advantage. Two lens contrast performance in all focal lengths are amazing, even at full aperture. In the end you can compare the focal length, the new lens distortion in the corners, and, in particular, the glare will better. USM may be for such a super-wide-angle lens is not so important, but the 17-35mm lens has a full-time manual (FTM) is very convenient in many cases. The lens of a "flaw" is the 17mm end of the barrel showed obvious distortion, hidden corners, full aperture resolution also decreased when the corner. At f / 5. .6 Gone dark focus, clarity also improved a lot. Other options: Sigma AF 17-35/2. .8-4 EX — it's only the main disadvantage of the camera is its glare at the highlights of this lens only under very severe ghosting and contrast is most lens style shima. In addition to this, the lens is worth considering.
A: In the EOS mailing list only a few of the only old man's comments, so this conclusion a bit difficult. Some reports said the old man's hidden corners and relatively large deformation, the official publication of the Canon in that Dark Corners of the problem has been solved in the new lens. Two lenses have ring USM, but the old lens is a full-time manual (FTM) function. .
28-70/2. .8L from the point of view can indeed show and focusing lens, so it can be considered to be the Canon lens series of miracles. The only problem is when the zoom lens elongation, when of course, this is the focal length of the lens, there are problems. Other options: tuli AF 28-80/2. .8 AT-X Pro — this is a very strong opponent, with the exception of Aperture's full open slightly soft. Machinery is very good quality.
Sigma AF 28-70/2. .8 EX - On the whole graph Korea that the dog can very, quality in addition to machinery outside. In the case of high light than the glare is very serious. .
Tenglong AF 28-105/.8 SP 2. — the only lens changing jiaoduan at both ends of the deformation is very serious. In addition to this, it vendors and other third shot or Basic equivalent.
A: From the optical point of view the differences between these lenses is very small, in short: very good. From the mechanical point of view, they have the high quality of L head. But between them there are some mechanical differences:. .
Therefore, from your own needs a lot of factors to consider. 70-200/4L for light weight, high quality of the lens is suitable for outdoor photography. 67mm filter diameter and EF 24-85 exactly match, for outdoor photography is made for each other. But it's (relatively) small aperture makes it with increasing distance that you want to use mirror less attractive. From that point of saying EF70-200/2. .8L is very good, it is in line with the EF 1. .4x still has a very good performance, combined with the quality of the relative EF2x after falling. This context, the old EF 80-200/2. .8 To rely on third-party vendors, and new out of the Kenko AF 300 1. .4 X pro seems to be the best option. Other options: Sigma AF 70-200/2. .8 EX HSM - this seems to be a very strong competitor. All the magazine tests show that it has and the more similar the performance of Canon lenses. The biggest weakness of the lens glare performance.In the light of circumstances, there will be a serious loss of ghosting and contrast, apart from this, the lens is a good choice.
Tokina AF 80-200/2. .8 AT-X Pro - TOKINA lens only made as strong as the only tank, but the poor performance of optics, particularly the telephoto end (in fact, very poor in all focal lengths). In Europe, only the lens often very cheap, you need f / 2. .8 Large aperture zoom lens when it is a good economical choice. However, in this case, the second-hand EF 80-200/2. .8 L is still the better choice. .
Tenglong AF 80-200/2. .8 SP — compared with other options not worth buying (e.g. front lens rotation, a very high price).
A: This comparison is very simple! Optical and mechanical structure are actually the same, only difference is the hood like the old lens is built. MKII the hood must be external, more effectively, but more. Comes with two lenses do not have the tripod ring, but you can buy from Canon, they can use 300/4L or 400 / 5. .6 L tripod ring. .
Here is how I think Canon Lens Work in MTF charts:.
I am from the MTF curves of the radial and tangential curve, three samples were taken, respectively, in the center, and the 10mm and 20mm from the central office. In the aperture all the contrast, clarity and f / 8, when the contrast, resolution of the readings were on average, did not add any weight. Therefore, a focal length of each end of the last four readings. .
Contrast: definition:.
Note: MTF-chart reflects only the lens focal length at infinity performance. The actual time taken may be different, because more recent performance of the lens focal length will deteriorate (usually is the case, unless it is a floating focus system) MTF-map and do not reflect the distortion, vignetting, color balance, and only a sharp performance under different aperture and contrast methods. .
Canon Canon EOS Lens Work II. FAQ 2 .4.
Canon EOS FAQ 3. .0. .
Canon EOS mailing list archive of the discussion.
Some magazine tests. .
Personal experience.
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