I’ve long since sent back the Sony LA-EA5 adapter and the Sony A7R IV A camera to Lensrentals.com and I have begun to review all the photos I took for sharpness and other criteria but the information I gleaned from this test are not dependent on the very detailed examination of individual files.
The questions I was trying to answer were:
- Does the LA-EA5 provide modern autofocus capability to the Minolta and Sony A-mount lenses that do not have motors built in?
- Will these motorless lenses prove capable of capitalizing on the enhanced autofocus functionality in real world situations?
- How does the A7R IV A camera compare to the A7 III with respect to tracking autofocus?
So, what did I find?
- The LA-EA5 does allow for some of the modern autofocus modes to function with these a-mount lenses. You can run tracking autofocus and you can use eye autofocus and most of the modes that you can use with normal e-mount lenses. One very disappointing exception is that the magnification setting that I like to use so much while making macro shots is disabled while in autofocus. It is only available in manual focus. And with this one exception the usefulness of the Minolta 200mm f\4 Macro lens is greatly reduced for me. I very often like to magnify the head of an insect to get perfect focus on the eye. Well, forget that. So, you can see that this first answer has been far less than a complete success. The lenses will allow me to take advantage of much better autofocus than currently available with the LA-EA4 but a key function is unavailable.
- So, for the autofocus functions that these lenses are provided with how do they perform in real world conditions? Well, once again, it’s a mixed bag. For relatively static subjects like a hummingbird hovering around a flower bush the autofocus worked quite well. With the flexible spot it actually stuck with the bird as it moved around the viewfinder. It succeeded in maintaining sharp focus on the bird. With dynamic subjects like bird in flight or, in my case, dog in run, it was a complete failure. Even if the tracking autofocus kept up with the subject, the lens couldn’t focus and capture the subject successfully. My keeper rate was zero. This was not a completely unexpected situation. I’m actually quite satisfied with the additional capability that the flexible spot and tracking modes provide for much less dynamic subjects. But I can understand why this will be a disappointment to folks who were hoping to use the old lenses for sports or wildlife. Of course, I’m sure that for those who possess much better technique in those photographic specialties than I possess there may be some methods of extracting better results than my abysmal record but I wouldn’t want to raise hopes too high about these types of applications.
- With respect to the comparison of tracking capabilities between the Sony A7 III camera and the Sony A7R IV A, it’s the difference between night and day. Of course, that because the A7 III doesn’t really have tracking. It has the flexible spot autofocus setting which does allow for the camera to try and follow the subject inside the viewfinder but as noted it’s quite limited to slow moving objects. The A7R IV A actually does track objects. From what I understand it’s quite rudimentary compared to cameras like the Sony A9 and Sony A1. From what I’ve heard these cameras have keeper rates that approach 100% for birds in flight and other very challenging applications. But the A7R IV A is still orders of magnitude better than my A7 III. But the disadvantage of the A7R IV A is the much larger file size. The 24-megapixel files of the A7 III are plenty big enough for most of my uses. The 60-megapixel sensor in the A7R IV A is a bit much for my tastes. Of course, your mileage may vary, especially if you specialize in landscape and sport.
So there you have it. I am actually looking forward to having the LA-EA5 available to me on the next Sony camera I own which I hope will be the A7 IV. Of course if Sony decides not to allow the A7 IV to autofocus motorless A-mount lenses with the LA-EA5 I will give up photography and take up Chinese calligraphy instead. But that’s just me.