Since you do not measure this lens, then as an eldest person, I will teach you some life experiences.
There is no doubt that this lens was produced by a famous Japanese optical company - Tamron. Without hearing that the wind is raining, this Pentax HD DFA 24-70mm f/2.8 ED SDM WR is a variant of the Tamron SP 24-70mm f/2.8 Di VC USD (A007). PENTAX's transformation of the optical part was just a matter of replacing the lens with its own HD film that had been whipped up and removing the original optical anti-shake function of Dragon (because Pentax had anti-shake), but it was just released. The price of over ten thousand can buy two and a half of the original Dragon.
However, actually changing the coating and removing the anti-shake does not make the optical quality much better:
The MTF curves of the two shots are from their respective websites. I dragged them into the CDR to do the auxiliary lines and scale up. It can be seen that whether the 24mm or 70mm end, the center resolution of the PENTAX version is indeed stronger and less noticeable, the edge resolution at the 24mm end is also slightly better, which may be due to the greater light transmittance. High HD coating; and to the 70mm end, Pentax version's edge sharpness is not as good as the original Dragon, which makes me puzzled. Although the sharpness of the lens can't be used to evaluate whether a shot is good or bad, most people always want to spend the same amount of money to buy more sharp, not to mention that they must pay more money. After all, when it is late, sharp The clear picture can be easily repaired softly, but it is difficult to repair the details on the soft picture.
So since I bought the Pentax K1, because of the prejudice against this lens has not been started, usually shoot only with the Sigma S35A and their own FA43 these two lenses. It was okay to begin with, but as the subject matter that needs to be photographed became more and more abundant, it gradually became clear that the lack of this lens was really out of place. Its focal length was undoubtedly the most mediocre but it was also the best. So went to Ma Yun's father's house to search for second-hand, 6,300 yuan price, 99 new fineness let me buy it without hesitation.
The fit with K1 is like this:
The coating is still familiar light green, and there is a clear difference from the original tawny yellow brown coating:
It is not very heavy to get a hand, obviously feel no sense of the Dragon original version at any time to fall; focus ring and zoom ring on the convex and the Dragon's original line is different, causing the Pentax version of the focus and zoom feel better some illusion. After plugging into the machine, due to the previously used Sigma S35A and FA43, the first impression of using this lens is that the original Pentax can focus so quickly, the second feeling is that the original Pentax can also be used to shoot sports people or things, visible I was so agony by the mechanical properties of those two lenses:
Let's take a look at the picture quality that the center and edges of the 24mm, 35mm, 50mm, and 70mm focal lengths can give you. Of course, in order to be as rigorous as possible in this rigorous environment, put the camera on my goddess of silk, M-beam exposure reflector delay 2s, and use the peak focus to check the corner and the center is not in the same focal plane on:
The format of the shooting is PEF (Pentax's own raw), open the non-adjusted data directly with PENTAX's own retouching software to enlarge 100% directly. Screenshot:
24mm center
24mm right
24mm upper right corner
35mm center
35mm right
35mm upper right corner
50mm center
50mm right
50mm upper right corner
70mm center
70mm right
70mm upper right corner
I don’t know if you can't see it in the small picture. In the case of full aperture, the center of each focal segment has reached a very good level of quality, and there is no problem with the number of hairs; the quality of the edges can almost reach the available level. In fact, shrinking the aperture to f4 can get a very good edge quality; the quality of the corner can be said to be useless, but in general no one will take things on the corner, even if the scenery is also mostly At least f8-f16 was received, but in actual use, this lens was able to achieve peak image quality almost under the aperture of f6.3-f11. This result is certain, after all, the original quality of this lens Tamron is quite awkward (Teng Long: Canon's 2470L2 than you do not know where I go, I laughed with him!).
When I used it to shoot some films, I realized the convenience of the zoom, which made me very excited. And I claim to be a fixed-focus fierce I actually recognized the quality of this zoom head, thought that the 6300 really spent, and came to a conclusion and a question: 2470 is very cute, why do you want to black it? After all, black should follow the basic law:
1, the front of the lens is not anti-fouling coating, oil, water, fingerprints are very easy to stick to the top, if you are often too lazy to go out and lazy do not want to always wipe the lens, may wish to give it with a high-end anti-fouling coating with a UV mirror;
2, zoom ring is very tight, really tight ah, tight like little Lolita (hey hello, why is not Xiao Zheng too!) of the larvae, the zoom ring position is not very scientific, this allows the hood to buckle after It is very hard to zoom in;
3, the ugly shape of the lens, but this is a problem before Dragon;
4, there is no MF switch button, the use of inconvenient to give people feel not grade;
5, the position of the focus ring is a bit unscientific, it is easy to accidentally touch after focusing to cause defocus, only through the use of a period of time to adapt to the new grip position to solve this problem.
There is something that isn't good but I think it's not a good place in my personal mind. If you look closely at the farthest star in the bottom-left of the paper, you can find a series of ghosts. Although the aperture used to shoot that map is f11 is not a ghost, but out of so many ghosts really make me a bit surprised, after all, had a very high expectations for the HD coating, the results I think HD coating and Tamron 1530 on Who is better for that new coating? Really, it's a matter of opinion. It can only show that the era of Pentax's coated myths is over, and we absolutely cannot boast that it is the first in Japan. However, ignoring my broken world view to score, this coating performance can indeed give 9 points.
Finally, the following summary: The focal length of this lens covers most of the focal lengths you need for daily shooting, and can provide you with pretty good quality and fast and stable focusing performance at any time of the day, ignoring the ugly shape, only less convenient The controls and the dirty front lenses can make you feel uncomfortable. If the new lens can be won around 6500, you ask me to invest in porcelain porcelain, I am a porcelain, that can really be considered passing through not to miss 6500 you can not afford to lose 6500 you can not be fooled.
The main wiring material in the network integrated wiring system is the Network Cable, including twisted-pair cable, optical fiber, optical fiber and so on.In order to protect the wiring line, ensure the neat and beautiful wiring place, but also to facilitate the later operation and maintenance, the integrated wiring system will also use some accessories, such as distribution frame, information socket, jumper, cabinet and frame, wire slot, pipe and bridge frame, finishing tools, etc.
For Example Patch Pannel:
patch pannel is used for end-user line or trunk line. Its function is to provide interface for the connection of optical cable, cable and other equipment. It is the most important component in the management subsystem, and also the hub to realize the cross connection of vertical and horizontal trunk subsystems.
Depending on the location, the distribution frame is divided into main distribution frame and intermediate distribution frame, in which the main distribution frame is used for the distribution of buildings or buildings, and the middle distribution frame is used for the distribution of floors.According to the different transmission medium, distribution frame is divided into twisted-pair distribution frame and optical fiber terminal box.
Network Accessories,Electrical Faceplate,Patch Panel,Wall Mount Patch Panel
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