How about a lens with a particularly long focusing stroke?

The difference of focusing stroke length is also designed according to the specific purpose of the lens, and there is no absolute good or bad. In other words, what kind of lens is suitable for long focusing stroke and what kind of lens is suitable for short focusing stroke depends on the specific use and cannot be generalized.

A purely manual lens requires a long focusing stroke.

In the film age, some old mechanical lenses used pure manual focusing without auto-focusing motor or other devices. If you want to focus, you must twist the focus ring by hand. The focus stroke of this lens is generally not too short. Because a long focusing stroke contributes to the accuracy of manual focusing, you can't just turn the focusing ring and focus will pass. When you turn the focus ring slightly, there will be a huge deviation, which is obviously not conducive to use, so the manual lens at that time was undoubtedly designed with a long focus stroke. At present, some brands still focus lenses manually, especially the focal plane in the professional field. Who is the guy who focuses manually by pure machinery? These lenses have a long focusing stroke, and they are all very smooth and properly damped. The process of manual focusing is also a pleasure.

The macro lens has a long focusing stroke.

Macro lenses, even autofocus lenses, have a long focusing stroke. The reason for this design is that the macro lens is mainly used to shoot tiny objects, and the distance between the lens and the object is relatively close when shooting, which will inevitably lead to a shallow depth of field. To focus accurately, you need not only a tripod, but also fine manual focusing to meet the focusing requirements. Many macro lenses often turn off autofocus and switch to manual when in use. Because of the theme, the focusing stroke of any macro lens is very long.

Advantages and disadvantages of long and short focusing strokes

The two types of lenses mentioned above have a relatively long focus stroke design, while the focus stroke design of the more commonly used autofocus lens is relatively short. The purpose of this design is because this kind of lens usually uses autofocus to shoot, so it is obviously advantageous to respond to autofocus instructions quickly in a short time.

Therefore, it can also be summarized as a lens with long focusing stroke, which is beneficial to manual focusing operation and accurate focusing, and is more suitable for shooting special subjects; Short focusing stroke is beneficial to fast focusing, which is more suitable for auto-focusing mechanism and more widely used for ordinary subjects.

For a single-lens reflex camera, the focusing process of a manual focusing lens is as follows. When you slowly rotate it by hand, the image on the focus ring flask of the lens will become clear bit by bit until it is in the clearest and most accurate focus. But people will never be satisfied. The photographer's hand must continue to turn the adjusting ring, hoping to get a clearer image. Until the image changes, the photographer will start to rotate backwards, and the focus ring will restore the image clarity to the best point.

One disadvantage is that the focusing stroke is particularly long. Because the focusing stroke is particularly long, the change of image clarity is not obvious when the focusing ring of the lens is rotated. That is to say, the focus ring curve of this lens is not sharp enough. After precise focusing, the image on the viewfinder screen seems to remain unchanged after turning the focusing ring left and right, at least the human eye is not sensitive to it, but the actual focusing of the lens is already the best focusing at this time. Therefore, in the actual focusing process, the photographer can find that the focus is far away, and then when the focusing ring rotates back, it will cross the best focus again. When the image becomes obviously worse, it will feel repetitive, which will seriously affect the focusing time and focusing accuracy.

Auto-focus is controlled by a motor to move the lens back and forth. Although autofocus has high focusing sensitivity, if the focusing stroke of the lens focusing ring is too long, the motor and battery can't stand it.

Hello, I'm a professional photographer and a semi-professional photographer cloning pandas. I'm glad to help you answer this question.

In the process of photography, you may come into contact with many lenses. You will find that these lenses, even between the same brands, feel different, and some are quite different.

For example, the focus stroke, some lens focus stroke is very short, and some foot stroke is very long.

In fact, I think in most cases, it is the designer of the lens who deliberately does it. Because different shots have different emphases, we can't generalize.

Let me take a distinctive macro lens as an example!

I have an old-fashioned macro lens, which is Longteng's 90-macro 272E E E. This is the focus stroke of this lens, which is very distinctive. Because it is a macro head, its macro part has a long focusing stroke. When focusing manually, the focal length can be adjusted flexibly and accurately. But when you take it as an ordinary fixed-focus lens and use it to shoot middle and far-end scenes, its focus stroke becomes very short. From a few meters to infinity, there is only a short section, and a little carelessness will produce a great span. It can be seen that this lens is obviously focused, that is, at macro, in order to focus accurately, the focusing stroke is very long, and the adjustment can be very delicate and meticulous. Cosco shooting is not the real "business scope" of this shot, but it is barely enough.

It is precisely because the macro lens is not so accurate when shooting long-distance scenes. So, although many people have always claimed that macro lenses like 90 or 100 can shoot guest portraits, why do few people do so in reality? That's because when shooting a subject at a certain distance, the focal length can't match the real portrait lens like 85 or 105 (the imaging part is not discussed here).

In a word, I think the length of the lens focusing stroke is actually related to the original design purpose of the lens.

Of course, some friends have always liked autofocus, so this has little effect on him.

That's my answer. I hope I can give you a reference. Thank you!

Of all the lenses, fixed focus is better than zoom.