Tamron AF 19-35mm f/3.5-4.5 là ống kính zoom góc rộng thích hợp chụp phong cảnh và du lịch với khoảng cách lấy nét gần nhất là 0.5m và góc nhìn 97-63. Ống kính nhỏ gọn và nhẹ, dễ dàng di chuyển và bảo quản với trọng lượng chỉ khoảng 300g và chiều dài 67.7mm. AF 19-35mm mang lại chất lượng hình ảnh cao và ổn định xuyên suốt phạm vi zoom, được tráng phủ nhiều lớp BBAR (Broad Band Anti-Reflection) của Tamron đảm bảo cho đường truyền ánh sáng ổn định và màu sắc hài hòa tuyệt vời với ảnh sắc nét. Méo hình được giảm tối thiểu kể cả ở khẩu mở lớn nhất, hiệu suất tương phản được tối ưu trên toàn phạm vi tiêu cự. Đi kèm ống kính là một hood cánh hoa, hỗ trợ chắn ánh sáng thừa lọt vào ống kính, hữu dụng khi chụp ngoài trời. Show
We are here with a lens review again. The lens we’re reviewing today is the Cosina-Vivitar AF 19-35mm f3.5-4.5 MC wide-angle lens. In fact, we should add the Voigtlander, Promaster, Phoenix and Promaster brands to the title of Vivitar and Cosina. And there is Soligor 19-35mm. 19-35mm f3.5-4.5 Lens Manufacturers Cosina has been an old company that has produced lenses for its own name and for other manufacturers for a long time. The companies that produce AF 19-35mm f3.5-4.5 MC lenses are Cosina, Vivitar, Voigtlander, Promaster, Phoenix, Promaster and Tamron. Although they are considered optically the same, small differences can be noticed in their mechanical structure. Of course, I did not have a chance to review them; I have experienced Nikon-compatible Vivitar 19-35mm and Canon-compatible Cosina 19-35mm. The rest of our article will be about these two lenses. We should also add Tokina and Quantaray in the 19-35mm lens group. It is rumored that Hoya produced their glasses, not Cosina. There are several different aspects from others. For example, diaphragm leaves are 6 leaves in Hoya productions and 8 leaves in Cosina productions. While the weight of Cosina is around 320 gr, it is around 385 gr in Hoya production. In this article, I have discussed the wide angle 19-35mm f3.5-4.5 MC lens produced by Cosina. This is the cheapest alternative to wide angle lenses, reaching true wide angle value in full-frame cameras. The cameras with Crop sensors will not differ from the 18-55mm kit lens. Therefore, it reaches its most useful state with full frame machines. We do not recommend using it on crop compatible cameras. Technical specifications of Cosina 1935mm f3.5-4.5 or Vivitar 1935mm f3.5-4.5Lens Name Cosina 19-35mm f3.5-4.5 or Vivitar 19-35mm f3.5-4.5 Building materials Plastic Weight 320g Length 7 cm Optical Element 13 elements in 11 groups Minimum focus distance 50 cm Number of diaphragm leaves 8 Anti-shake non Max- min aperture 3.5-4.5 to 22-29 (cosina 20-25) Filter diameter 77mm Made in Japanese Is It Enough For 19mm Wide Angle?19-35mm is it enough for users who are used to lenses like 16-35mm? In fact, “How important can a focal length of just 3 mm be?” You can also think of it. Obviously, this is not the case when wide angle. A wide angle of several mm focal length can change our viewing angle a lot. Therefore, the angle difference between 19 mm and 16 mm should not be underestimated. However, there is no need to exaggerate. Nor does it increase the angle of view twice as much. It is expanding a little. The adequacy of this amount will vary according to the user. For example, it was not enough for a friend who got used to 16 mm 19 mm. But for someone like me using a lot of alternative lenses, 19mm offers a perfectly adequate viewing angle. Cosina-Vivitar AF 19-35mm f3.5-4.5 MC Physical Structure-AppearanceThe Cosina or Vivitar 19-35mm lens is made of plastic and is highly portable. Around 320 g in weight. It is very practical to carry with this aspect. It is about half the weight of 16-35mm lenses that are normally used. The plastic structure has a positive effect on transportation, but it can become very suitable for scratching-crushing in terms of durability. Because the Vivitar in my hand was scratched due to a simple rub and paint fading occurred. Although it does not interfere with use, it does not look aesthetically cosmetic anymore. Besides its weight, it is very suitable for carrying and using length. 7 cm long. It is about 4 mm longer during focusing. The bayonet part is metal. It doesn’t feel like it will break like plastics. Speaking of focus, the focus speed is pretty good. I liked the near-far focus transitions. I can not say that it is very quiet since there is no ultrasonic motor; but not like a diesel engine. It makes some focus noise. Even though its performance decreases in low light, it still does. Nikon and Canon Compatibility DifferenceThe ones produced for Nikon differ from those produced for Canon. My Vivitar is for Nikon and Cosina is for Canon. There is a diaphragm ring in Vivitar, but not in Cosina. But just the opposite; While Cosina has af-mf button, it is not in Vivitar. In Cosina, we can control the diaphragm electronically from the sacdevce machine. In Vivitar, you have to control the automatic-manual focus transition from the camera. I wish there were both the AFFF button and the diaphragm ring for both brands. Controls would be easier. One more note: the ones for Nikon are like 5-pin, D-version lenses. If you are going to use it in full-frame cameras, it is no problem. However, since entry-level Nikon cameras do not have a AF engine, you cannot use auto focus. Disadvantages of Cosina-Viviar AF 19-35mm f3.5-4.5 MCThe front elements rotate during focusing. One of the dislikes of this lens. Using a polarizing filter becomes difficult. But the sharpening ring rotation angle is about 45 degrees. So just turn the lens about 45 degrees to switch between the nearest focus point and the farthest focus point. This is better than nothing but with wide-angle lenses, the landscape is taken heavily and the CPL filter is often used. When you use this lens, you should also adjust the filter every time you make a sharpness; For your information. Another disadvantage is that it does not have a fixed aperture value. While 19 mm gets the maximum f 3.5 aperture value, 35 mm gets the maximum f 4.5 value. Features This is a situation that can force manual mode users. You may need to change the shutter speed each time during focal length transitions. Of course, this is true for the clearest diaphragms I wrote. Otherwise, you can take pictures with the same aperture and shutter speed at all intervals when you receive f 5.6. In fact, when using wide-angle lenses, the depth of field is not desired to be shallow; that is, it is appropriate to keep the diaphragm high. Therefore, if there is no special case, the lens can stop at f 4.5 continuously. Cosina, Vivitar AF 19-35mm f3.5-4.5 MC Photo QualityLet’s come to the photo quality. As is known, wide angle lenses may not provide the sharpness it provides in the center at the sides and corners. Although the edge and middle photo quality are close to one in today’s expensive wide-angle lenses, this is not the case with our 19-35mm lens. In the wide span the center is fine but not good at the edges. If you hold the diaphragm like f 8 or even f 11, the edges will recover. The colors seemed to me with a slight contrast. I saw a little saturated in the photos. But it’s not a glaring contrast. Acceptable. Already the colors or contrast parameters are now easily adjustable on the computer. One should not worry too much. Bokeh is not felt much, frankly. I was hoping it could give beautiful bokeh thanks to its 8-blade diaphragm leaves, but it’s not very selectable. Your focus point should be very close so that bokeh can appear. Bokeh does not occur much, since close-up sharpness is not widely used in wide-angle lenses. Portraits that are likely to be taken in street photography when using 35mm in one place where bokeh may be needed at a wide angle. Other Features of Cosina, Vivitar series 1 19-35mm f3.5-4.5 MCOur lenses are MC coated. Thanks to this ‘multi coating’ coating, light glows slow down to some extent. I cannot say that it was very successful. But it is still acceptable. It is not possible for light to enter the frame when it is wide. With the MC coating of these lights, the dimmer diaphragm can cope with only one. No matter how successful he can be … One of the most important situations in wide-angle lenses is the inclination of vertical or horizontal axes. So distortion. Our lens performs outer pillow distortion, especially in full frame, especially when it is very closely focused. It is not possible to be detected at 19 mm; easily noticed. At 35 mm, it is minimized, but it can still be selected if you look carefully. However, as distances increase, this distortion can become invisible. Distortion is not detected neither horizontally nor vertically even at 19 mm at a distance of about 10 m. In crop machines, the closest distortion at 19mm is understood very little. 35 mm is very clean. There is no problem. After focusing 3-5 meters away, it gives a very clean, distortion-free image at every focal length. Our lens Cosina (or Vivitar) AF 19-35mm f3.5-4.5 MC is successful in chromatic aberration (CA). Although I observe a little bit of CA in the open aperture, it is almost zero in the shorter apertures. It is difficult to observe, even if CA occurs across wide-angle lenses. Since the viewing angle is very wide, glare is invisible. They do not stand out in the composition. Also the pre-filter diameter is 77mm. Beware of Backlight!After publishing my article, I wanted to add a situation that I encountered in several different shots. Light reflections coming from the crosses in disturbed weather and especially in white artificial light environments create disturbing explosions that foreigners call ghosts. It is very difficult to control when the angle is also wide. It pushed me very hard, both indoors and outdoors. I did not have the sun visor, which I saw a little unnecessary below, and I pretended to be a perfect monkey to prevent these reflections of light. I share the examples below. Finally, let me talk about lens hood. Its length is not even 2 cm. A huge sunshade. I don’t think it will do much. It also creates a huge obstacle to move. If you flip it over, it makes the lens almost 2 times thick and prevents it from entering the bag. The kind that will make you say ‘better not to be’. I don’t even remember using it at all. As a result:In the first quarter of 2020, Cosina can be found on Vivitar AF 1935mm f3.5-4.5 MC global websites, with a second hand between 80-100 dollars. The cleaner is around $ 150. I do not know if there is a zero market, but I was able to find a place or two that sold zero. They give twice the price of the 2nd Hand market. From wide angles without alternative, which can be bought at these prices. I have not come across another lens that is both full-frame compatible and capable of providing a wide angle of 19mm and is so cheap. Of course we should expect it to work wonders optically. There are also ghosts he created. But I must say that it is a lens that will save lives in difficult times. Ease of transport is also a plus. |
