What is the BACK FOCUS or FRONT FOCUS problem? How to Solve?
In this article, I will focus on the Back Focus or Front Focus problem and its solutions. After reading our article, you will stop complaining about the lens focusing incorrectly.
In today’s photography, autofocus lenses are almost indispensable. Too many pardon lenses are produced and sold. These lenses, which have such a large share in consumption, do not have a chronic problem either. The back focus -front focus problem is also one of the main problems of af lenses.
What is the back focus- front focus problem?
We can define this problem as focus (or back) instead of where it should focus briefly. It shows the selected point during focusing on the camera as if it was focused, but if taken careful after shooting, it is understood that the desired point is not focused. In such a situation, it means that the problem mentioned has happened to us. If it focuses forward from the desired, it is called the Front Focus problem, and if it is the desired back, it is called the Back Focus problem.
The important thing is not to have the problem; understanding the problem. It is not that easy to understand. Let’s explain what needs to be done to find out simply whether there is a problem in the amateur home environment: We bring the camera to single point focus and af-s mode. Fastening on a tripod will greatly facilitate our work. Generally, specially produced charts are used, but not necessarily. We can also use a full A4 sheet or your school ruler as a scale. Let’s put our scale on a flat surface and position the machine at a distance of about 45 degrees with a distance of about 1 meter. The whole setup is that simple. Now it is time to take the picture. The most important thing to take into consideration when taking the photograph is the point where we focus. For example, let’s clear the 5cm point on our scale. Then, when we look at the details more carefully in the computer environment, the area where the focus is 5cm is no problem. If the focus is a few mm in front, focus on the front; If there are several mm of back, there is a back focus problem.
I suggest you try the issue I mentioned above in at least 3-5 photos, not in one photo. From time to time, we may miss the focus or shoot the wrong spot during shooting. It would not be correct to make a decision by looking at the single photo.
Let’s come to the solution of the problem after the problem determination.
The solution of the back focus or front focus problem:
First solution: Some advanced cameras have focus settings. With this setting, you introduce the problem lens to the camera, and each time it uses the lens, the machine automatically corrects the focus problem itself. For example, for Sony mirrorless and DSLRs, this feature is called af micro tuning. When the lens is attached to the camera in the micro-adjustment part, correction can be made as 20 degree scales in + or – direction. This setting is listed as macroadjustments in nikon and af microadjustments in canon, and its usage is similar. Some brands can record several lenses, while others can only keep one lens in memory.
If you are going to make adjustments on the machine, you should try and do several times. So you have to study well whether the correct result gives +5 degrees or -15 degrees. Otherwise, we are not considered to have fully resolved the problem; we just reduce it.
The second solution is to reach a solution by showing technical services that can easily solve such problems. Generally, many technical services in big cities can solve such problems, but unfortunately there is not even technical service in small cities, so it is much more difficult to solve. The most guaranteed will be to contact a technical service and deliver it by cargo. The cost varies between 50 dollars or euros.
As we mentioned above, the back / front focus problem is not a big enough problem with hair. The solution is simple. I have a 20-year amnesty lens and when I discovered this problem, I recorded the lens on the camera and solved it with one set. I have been using it for a long time.
Good ligth….
