Has the AF gotten faster further more?

This post was originally published on FUJIFILM X Blog

The X-T2 is officially announced finally. The spec is disclosed, and the camera is displayed at selected locations worldwide. Some of you may have already tried it. And as it turns out, one of the main interests among the users is the enhanced AF performance such as the new AF-C Custom settings. We have been hearing the on-going discussion that "the AF feels faster" and that "subject in motion can be tracked rather easily"
So has the AF gotten really faster? The answer unfortunately is "No". The AF fastest is still 0.06 sec.
But even then, many of users still would say that "the autofocus of X-T2 still feels faster".

In the article, we mentioned that in order to achieve the fastest AF speed, phase detection AF needs to be enabled. The fact is that the new X-T2 makes use of the phase detection AF more than any other previous models.

The improvement can been seen on the low contrast subject and high frequency subject. They were improved with when the X-Pro2 was released. But with the release of X-T2, it has dramatically improved even more, particularly for focusing on hair and feathers of the wildlife animals.

In case of mirrorless cameras, when the phase detection AF continues isn't working, the camera quickly switches to contrast AF to find the focal point. Then, the camera will be able to focus on the subject for most of the time, but the tradeoff with this is that it will take a longer period of time to focus.
With the research we conducted internally, the result showed that the phase detection worked for 1/3 of the time, and the camera had to switch to contrast AF for the remaining 2/3 of the experiment.

This is not because the device is incapable. Rather the developers believed there are rooms for improvement in algorithm. But the working on the algorithm is a time consuming process.

First, various patterns of charts are created for those subject that didn't focus well. Then, the adjustments are made in the sequence and parameters little by little to have better analysis. When we have better understanding of the pattern, then the actual tests are conducted in the field. The results always differ when you actually try it in the field, simply because the environment is never the same for even once.

The development of AF algorithm is a repetition of the process. But to pull out the maximum performance out of the device is what the users want, and that is what developers want to achieve.

So what happened at the end? Their efforts resulted in doubling the performance. Previously, phase detection AF was utilized only 1/3 of the time, but with the improved algorithm, phase detection AF is now utilized for over 2/3 of the time.

There are still the remaining 1/3 of case where the phase detection finds troublesome to focus, but the developers are working hard to make the improvement. So let's hope that one day it will be 100%.

Mechanically speaking, the algorithm is implemented on the X-Processor Pro. It will be processed on chip, so it can act very quick.
So now the question is "Is it only for X-T2?"

You do not need to worry. It is processed on chip, but via rewritable "DSP" circuit. It means that it can be updated via firmware update.

The X-Pro2, which has the same X-Processor Pro, will also benefit from the improved algorithm. We are at the final stage of testing and tuning, and the new firmware will be ready in October as Ver.2.00. Let's wait for a little bit more.