: What is a micro-USM, ring USM, AFD?.
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 than ring USM slower, however, and AFD/MM compared to pretty fast. Low energy consumption. In extreme temperatures. AFD/MM: 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 to consider whether it is in the State, AF, manual focus it allows you to do a bit of fine-tuning or completely change the position of the focal plane. Obviously, this function only in a "single autofocus AF mode" makes sense.
Q: Does Canon have compatibility issues between components? . .
A: in the EOS system does not have 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 "restrictions" is a 300/4L IS increasing distance from the lens and mirror 2x (600/8).
With time, older EOS body IS feature turned off. However, the 600 / 8 combination is no significance, because of its poor quality optics, so it is only a theoretical problem? . .
Q: does the third vendor product compatibility problem?.
A: the old Sigma and Tokina lenses (93 years or older) in the newer EOS body (EOS 5/A2 (E), EOS 50/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 shot away.
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 — temporarily — can be resolved, but there is no guarantee that won't happen, because Canon never provide any relevant body — the lens information communication. For example, the recent discovery of a third-party manufacturer lens and the new Nikon F5 has a problem. If this can happen, so for the next generation of the EOS body the same thing can happen. So buy a third-party product must think twice before.
Q: Canon Teleconverter how? . .
A: there are now two additional Canon from the mirror.
Extender EF 1. .4 X II (minus 1 block aperture). .
Extender EF 2. .0x II (minus 2 retaining aperture).
They are the best on the market Teleconverter, Canon 135mm, but can only be used for more than a fixed focus lens L, and the Canon 70-200/2. .8 L and 100-400/4. .5-5. .6 L IS. .
In the third manufacturers is quite a nice cheap alternatives:.
Sigma AF 1. .4 X APO EX. .
2. .0x shima AF APO EX..
Kenko AF Pro 300 1. .4 X. .
Kenko AF Pro 300 2。.0x。.
The only match the Sigma Sigma EX Teleconverter 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. .
While increasing from Kenko mirrors you can match any lens, since it has not raised before the Group of lenses. But the Kenko.
Pro series is more than 200mm telephoto lens optimized for use in the standard zoom head is meaningless. Some third-party vendors with Teleconverter lens do not follow the rules above (compatibility issues?). .
Don't expect to use the additional margin mirror 2x what miracle, regardless of whether you use a Canon EF2. Kenko AF PRO .0x or 2x. Only in some very high quality lens, such as 300/2. .8 (IS) or.
400 / 2. .8 II (IS) can try to get good performance. .
Q: Canon L lens and increasing distance lenses, performance?.
A: It's hard to measure the performance using the Teleconverter lens after, because it is too dependent on the design of this lens, of course, also depends on the quality Teleconverter. 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 will give two reduction lens (with a very good lens becomes a normal double lens). Most of the design of the lens, use two double margin requirements mirror is usually too high, so in the 75-300.
USM like the below-average use the Teleconverter lens is usually meaningless, but the Canon Teleconverter is not 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 300 (Kenko AF.
Pro) are very good choice, is basically the same level as the original Canon lens. So, if you want to save the economy on both could be considered. Should pay attention to the compatibility of the future is still a problem. .
Q: more distances and small aperture lens?.
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.
There is also a feasible approach to make the small aperture lens and Teleconverter with Canon's autofocus can. Canon Teleconverter three additional contacts, use a thin plastic film to block them. This may be such as 500 / 4. .5 +1. .4 XTC. .
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. .
Do the test, the result is still far less than acceptable level (at least for the slide and poster, this is the case).
Q: Canon L lenses have anything special? . .
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.
Q: CaF2, SUD & UD What is the difference between? . .
A: chromatic aberration for telescope head is a widespread 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 UD, but still lags behind that of CaF2, up to now only in 400/5. .6L.
Shot. According to the magazine's test, sure that even the ordinary UD glass is also the third vendor APO lens than good. .
Q: Canon of SSC (Super dispersion coating) coated lens quality?.
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 be better, the magazine's test shows. Once users report that Pentax lens (with SMC coating).
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. Such as 17-35L lens than its predecessor, the ability to like a lot of glare, glare may be the role of aperture. .
The above discussion it seems a bit far-fetched, since there is no strict test data.
Q: What is the cheapest way to do with an ordinary lens macro photography? . .
A: there are many ways you can get higher magnification. Close-up filter, and then circle close-up is simple and cheap solutions. The following table lists some useful combinations:.
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. .
Vivitar AF 100/3. .5macro lens.
Q: The third is the EOS lens manufacturers in the field of good alternatives to it? . .
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 an alternative to the Canon brand. However, in addition to quality, the. .
There is 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 situation had occurred.
Many times! The reason is neither third-party vendors to buy the lens mount of the patent, and no lens and body of the communication protocol, they are. .
By reverse engineering to do them by analyzing the fuselage and the signal lens to simulate this critical section. Clearly, this approach is not possible without problems. The earliest illnesses at EOS A2E 5/.
Body, the Sigma lens because of the frequent operation issued aperture strange sound. After the upgrade the camera firmware on all normal. And to the EOS 50/Elan II. .
After publishing, 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 when released. This time more over, most of the third lens manufacturers, and even the latest models (such as Sigma's EX lenses), the new machines are not working properly, the aperture will be a serious misuse, such as will appear mildly to can not auto focus problem. 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, the we can be accused of causing them trouble Canon, but on the other hand, all the Canon lens, including the old lens never can and new machines with very good.
We may have to face this compatibility issue, until the third party is willing to spend big money buying proprietary lens mount. .
Q: which lens is floating on the focusing mechanism?.
A: floating focus mechanism indicates that the performance would be relatively close focus better. Magazine tests often only measure the lens set at infinity focus, but the actual filming in the performance of distance is likely to become poor, especially for wide-angle lens and large aperture lens even more so. Listed below to the EOS mount lenses focus 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. .
Q: what the lens aperture with anti-glare (FCD)?.
A: In the case of high light than the glare is a key issue. There are three general ways to reduce the glare, ghosting:. .
1, anti reflex coating of the lens.
2, electrostatic flocking. .
3, anti reflection structure.
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 to a certain small, simply stated. .
Manufacturers have made efforts 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 USM macro. .
Canon EF 300/L USM 2. .8.
(*) = According to zoom position to move the FCD. .
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):.
Q: What is it? It done? How does it work? What is the limit? . .
A: simply put: camera vibration are the main cause of blurred photos. Especially for the telephoto lens and low-light conditions. Solution to this problem is often that a larger aperture of the lens (more expensive) or higher sensitivity of the film. Canon on the issue of a new solution is the stability of the image itself. Camera movements were two gyro sensor to detect angular velocity is vibration. This message is used to control moving a set of lenses, making its optical axis offset the correction movement. The result is a visible improvement in the limit of the handheld. For example, the 300mm lens with 1 / 60 seconds may also be successful, and not have to 1/250-1/300 seconds, roughly equivalent to 2 block aperture. And the results of the traditional hand-held shooting compared to the same sharp clarity. Use of IS and will not bring the quality of reduction (of course using the tripod will be more sharp)! Obviously this technology still has the scope of application, the two steps of aperture of the increase is only "simulated." .
Aperture f/5. .6 of lens aperture IS still f/5. .6 lens. You may like to use f/2. .8 lens received very shallow depth of field, which only you can use a large aperture.
You get the aperture is only a few files to your frame rate a little more slowly, for example, you can at 300 / 5. .6 With the 1 / 90 seconds, while the real 300 / 2. .8 Can 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. .
Q:IS and tripod with?.
A: there are some rumors that the tripod when using a tripod would be counterproductive to use IS function, IS will destroy the quality. This is clearly nonsense. You can see the instructions inside: "When the camera tripod at the time of the IS function, do not switch to 'I'. IS this may cause malfunction. The tripod when using the camera to turn off the IS" . Moreover, this shows only a few shots on the following valid:. .
EF 28-135/3。.5-5。.6 USM IS 。.
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) explained:.
"IS device used to correct the vibration. When the vibration level is less than the system detection ability when using the IS may have photos 'increase' unexpected fuzzy. Therefore, in this case you should close the IS function to IS lens group was locked in position. When the IS feature turned on De time, IS lens group because of Mo You are locked, then there may be electromagnetic coil Dai Dong. when not enough Yundong be IS Xitongjiance to the time of the lens movement may be a Dianzi the influence of feedback, this feedback like that we are all familiar with radio feedback circuit of the ringing noise.It's the result is that the camera on the tripod IS the lens group is moved. Unless IS is turned off, IS the lens group is locked. ”。.
Canon has just launched the next generation of the IS professional lenses. These lenses have a "tripod detection" function, meaning that the IS lens is no problem to use a tripod, and, IS mirror can correct camera movement caused by small vibration. Until now, the lens included with this function. .
EF 300/2。.8 USM L IS 。.
EF 400 / 2. .8 USM L IS. .
EF 500/4 USM L IS 。.
EF 600 / 4 USM L IS. .
Q: more about Canon EF 28-135/3.5.5-USM IS .6.
A: This is the only one IS a series of wide-angle focal length of the segment that contains the lens. From the optical quality that it and the popular EF24-85 / 3. .5-4. .5 And EF28-105 / 3. .5-4. .5 Par. Performance than those of non-IS lens is said to be the same, or even slightly better. But the ratio of 28-70/2. .8 L difference. .
(This is 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 you can get the "end" 28mm 1. .5 retaining minimum aperture, (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, this is probably the only lens Canon best mirror fits travel lens.
Q: more on the Canon EF 75-300/4-5. .6 USM IS. .
A: this lens optical performance and it turned out that only 75-300mm similar to 300mm-very soft, 75mm to 200mm.
Is not bad. It is very attractive because he can use the 75mm segment 1 / 15 seconds can also illuminate a clear image. 1 / 60. .
Second paragraph 300mm. 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 compared slow. Overall, this is a pretty good lens, if your main image smaller imprint.
Q: more on the Canon EF 300 / 4 L USM IS. .
A: the consumer-level compared to the 75-300IS.
Only the lens is totally different! Quality and mechanical quality are worthy of the "L" class lenses. Tests show that it a little better than poor old 300/4L. Only IS lenses may be a bit more prone to glare, because of the relatively large number of lenses (13 to 8). In addition to the standard IS models, it also provides a new. .
"Shake" mode, the adjustment of 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, you can tie in with Canon IS function of the distance from lens to use, this is the previous frame EOS50 does not necessarily mean that the old machine (including EOS5, 1N) you can only fit 1. .4x.
TC IS function to achieve. .
Q: some more on the Canon EF 100-400/4.5-5. .6 L IS USM.
A: only the lens of the early products of the users have been reflected in the performance of the 400mm end it did not reach a perfect level. Subsequently, however, these early products BUG has been amended, a formal test that it's really a good 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 MTF curve of a book 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. .
11.800/.2 monster, probably no one wanted to. Like 300/4L.
IS the same, only the lens provides two IS modes - a normal mode, you can correct the image fuzzy in both directions, the other is the "pan" mode, only the correction of vertical vibration. IS function as normal, can "get" 2 block aperture, 400mm side so you can use 1 / 125 sec (or less) hand-held 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.
Q: Review of the existing IS lens. .
Comments:.
IS-mode 1 = normal mode, shooting stationary objects. .
IS-mode 2 = flat wave mode, shooting a horizontal movement of objects.
Test = camera tripod can use the IS function tripod. .
Some frequently asked questions: comparison of the lens.
Q: Canon EF 24-85/3. .5-4. .5 USM vs Canon EF 28-105/3. .5-4. .5 USM and Canon EF 28-135/3. .5-5. .6 USM. .
IS。.
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. poor price .8L on or off. Generally, the wide-angle-geometric distortion relatively serious, remote imaging a little soft, there is a shortcut for USM motor, and full-time manual functions. Filter dimensions are completely different (58mm.
(28-105), 67mm (24-85), 72mm (28-135)). 28-105 and 28-135. .
IS for inclined to portrait photography of people, and 24-85 for inclined to photography people better. 28-135 IS obvious.
Would be more practical, because it has the IS function, as explained above before. .
Other options:.
In the Canon's products, there is an old EF 28-70/3. .5-4. .5 MK II. .
Once considered a similar lens in one of the best. Since 1992 has been cut off, so now it is difficult to find. However, with this lens, use spaced polarizing Prism will be very painful because the former group of lenses in zoom and autofocus will rotate and mirror drum income. No USM motor, but the optical quality is 24-28-105mm 85mm and are much better.
If you would like more money, then the Tokina AF 28-70/2. .6-2. .8 AT-X Pro II. .
Should 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, said from the optical weight is also very attractive, but and Tokina than the slightly Chailiaoyidian. (Please note that third-party vendor product compatibility issues). .
Q: Canon EF 50/1. .4 USM and Canon EF 50/1. .8 MK I and MK II.
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. .
MK I and II optical structure is the same, just the color balance perspective there is little difference between MK II is an old version of the neutral and warm. However, the mechanical structure with two lens there is a huge difference! old MK.
I shot a metal mount and sturdy construction, the new MK II is very loose. Have the MK II has been the center of the lens (not balanced the sharpness of the) report. .
50/1. .4 this one is clearly faster than 50/1. .8 MK.
Many have strong structure II. In addition it is equipped with micro-USM motor, and provide full-time manual (FTM) function. Generally, this lens is the best option, but contrast a bit on the expensive (about 50 / 1. .8 Four times the price). It is better to go from second-hand market, the old 50 / 1. .8. .
MK I, but this is a very difficult thing.
Q: Canon EF 75-300/4-5. .6 USM (IS) and Canon EF 100-300/4. .5-5. .6 USM. .
A: for the two lens comparison problems probably EOS newsgroups and mailing lists of most frequently asked questions. Although optical structure is different, the two are very similar to the performance of the lens:.
Wide-angle end is very good. .
200mm may also line.
Telephoto end is very soft (300mm). .
This looks very good, but for the vast majority of 75/100-300mm zoom lens is the same for both. If the quality from the machine, two different lens. 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:.
In the Canon (Canon or third vendor) only one performance of the lens quite good but can afford from the 100-300mm zoom lens, is probably the 100-300/5. .6 L (not an expensive 100-400L). You must clear the quality of the extra price to pay more, but you will find in the secondary market is still very cheap, (for more than a new one 100-300/4. .5-5. .6 USM you a little bit ). It does not USM motor, but also push and pull type zoom institutions, unfortunately, the focus lens when the former group will rotate.Lens mechanical quality than those consumer level cameras, but also not bad. Because a CaFo-and UD lens, image contrast and sharpness are quite good.
That third-party lens, often frustrating. Dragon 70-300/4-5. .6 LD seems to lower the market a choice. With Nikon's Nikkor 70-300/4-5. .6. .
ED has 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 interesting, but few users have a good evaluation..
(Please note that third-party manufacturers, product compatibility problems).
Old L head comparison:. .
Q: Canon EF 17-35/2. .8L USM and Canon EF 20-35/2. .8L.
A: comparison between the two lenses more intractable, as the new head from 17mm wide-angle end of the beginning, so the following recommendations are only limited to the 20-35mm focal length end of period. The overall performance of the two lenses are very good, but the old lens in the resolution may be a little a little advantage. Contrast the performance of the two lens focal length in all the high end are amazing, even if the same is true when the full aperture. In the comparable focal length side, the new lens in the hidden corners, deformation, especially glare would be better terms.USM may this ultra wide angle lens, and is not so important, but the 17-35mm lens with full time manual (FTM) in many cases are very convenient. This lens is a "disadvantage" 17mm-showed noticeable barrel distortion, offers a new, full open aperture corner resolution. At f/5. .6 dark Coke vanishes, the definition also improved a lot.
Other options:. .
Canon EF 20-35/3.4. .5 .5-USM-this is no mechanical quality of the lens and a comparison, but in addition to the optical quality aperture full open are quite good.
Tokina AF 20-35/2. .8 AT-X Pro -. .
This lens distortion is very small, even in 20mm side. When you full aperture Imaging softer, small aperture can improve the mechanical aspects of this lens like a tank.
Sigma AF 17-35/2. .8-4 EX -. .
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.
Tamron AF 20-40/2. .7-3. .5 SP - the whole is a good choice, in addition to aperture all the performance a little worse when. Deformation than the same time several shots to the big. .
Q: Canon EF 28-70/2. .8L USM and Canon EF 28-80/2. .8-4L USM.
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 the time when the zoom lens extension, of course, is the focal length of the lens segment of the problem there. 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.
Q: Canon EF 70-200/2. .8 L USM and Canon EF 80-200/2. .8 L and Canon EF 70-200/4L USM. .
A: from optical point of view the difference between these cameras are very small, in short: it's all very good. From a mechanical point of view, they have L head of high quality. However, they still have some mechanical differences:.
Therefore, starting from the needs of your own there are many factors to consider. 70-200/4L demand for lightweight, high-quality lens, people are very good - very good for outdoor photography. 67mm filter diameter and EF. .
24-85 exactly match, for outdoor photography is made for each other.
But it (relatively) small aperture makes it for people who want to use with Teleconverter less attractive. From this point EF70-200 / 2. .8 L very good, it is 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 you must rely on third-party manufacturer's product, the new out of Kenko AF.
300 1. .4 X pro seems to be the best option. Other options:. .
Shima 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. Light than in the case of large, there will be a very serious ghost and contrast losses, in addition to this, only the lens is a good choice. .
Tuli AF 80-200/2. .8 AT-X Pro —.
Tokina lens only produced as strong as the only tank, but the poor performance of optics, especially 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, used the EF. .
80-200/2. .8L is still a better choice.
Tamron AF 80-200/2. .8 SP - compared with the other options are not worth buying (for example: the front lens rotation, very high price). .
Q: Canon EF 200/2. .8L USM II and Canon EF 200/2. .8L (MK I).
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. .
Two lenses are not complimentary tripod jiehuan, but you can buy from a Canon company, they can use the 300/400/5 4L or. .6L jiehuan of tripod.
Here is how I look at the Canon Lens Work book's MTF chart:. .
MTF curve I radial and tangential curved respectively take three samples, each in the Center, and the distance between the Centre and 20mm 10mm.
Department. 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. .
Note: MTF-figure merely reflects the lens at infinity focus. Shooting for the actual time may vary.
Because the more recent focal length lens will show deterioration (usually is the case, unless it is a floating focus system) MTF-map and do not reflect the distortion, vignetting, color balance, but simply a manifestation of different sharpness and contrast under aperture method. .
