j4nu
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 Re: Sony 85mm f/1.4 GM II Announced—Pre-Orders Now Open! | |
Steve Spencer wrote:
j4nu wrote:
Steve Spencer wrote:
j4nu wrote:
Steve Spencer wrote:
JD07 wrote:
I'm happy to be corrected, but I thought the eye AF issues with the A7IV were supposed to be corrected by a firmware update (possibly v1.1 I think) some time ago?
Steve Spencer wrote:
j4nu wrote:
Orsonneke wrote:
I have the 85 GM ii in use since last week in Belgium.I am astonish how exact the AF is compared to the sigma 85.The 85 GM ii is exact on the eye ball , ALSO on fast moving people.Corner sharpness is better too (perhaps not relevant for portrait) and much less barrel distortion compared to the sigma.I only tested the 85 GM ii on the a9iii.I would definitely buy the lens again.I sold the sigma
I hope this doesn't mean that you need A9III to get accurate eyeAF with the GM II  ...
Do you hear any AF noise like @Donbioh@@@@@@@@ does?
Keep in mind Don was using the A7 IV which is behind other current offerings from Sony in just the area he was having problems. Here is a quote from the DPreview discussion of this camera's AF:
"However, we did find that the a7 IV can tend to very slightly front-focus when using Face/Eye detection, leaving the eye-lashes perfectly in focus but the pupil very slightly soft. This isn't going to be an issue for everyday social photography, but if you're trying to shoot portraits with shallow depth-of-field, the a7 IV doesn't seem to be quite as dependably accurate as the previous generation of Sony cameras."
It seems quite possible that he isn't seeing a better hit rate for 85 GM II over the Sigma 85 DG DN because the camera he is using can't deliver that hit rate.
It may not take an A9 III to see that hit rate either. Here is a quote from the DPreview discussion of the A7r V's AF:
"The good news is that, for the most part, you don't need to think about or edit much of this at all. Choose AF-C and a small tracking AF point and the camera will track whatever you point it at pretty well. Specify that you want it to focus on Humans (just faces and eyes, perhaps) and it'll do extremely well. In our practice focus didn't always perfectly hit the subject's pupil but it's only the camera's high pixel count that allowed us to see any imprecision: we can't think of another camera or AF method that would have delivered better results."
Of course we will have to see, but there is good reason to hope, IMO, that the 85 GM II will have great AF with the latest cameras that are capable of providing the same precision that the lens is capable of providing.
I am sure it has been improved with firmware, but the A7 IV does not have the sensor scan speed of the A1 or A9 cameras and the extra calculations that provides, nor the advance AI module of the A7r V, so the 85 GM II might well work with those more advanced cameras even though it struggles with the A7 IV. That struggle could be the camera more than the lens.
Yes, you are right, but the Sigma focuses on the eye just fine in this case so it shouldn't be the matter of the camera here.
I'm sure that A7RV will recognize the face faster due to AI and A9III will track better due to faster sensor read out, but come on - A7IV should be perfectly capable of capturing kids doing their stuff...
I also expected GM II to be excellent when it comes to AF and I am surprised reading this report...
Also, these are 2 different things:
* eye(lash)AF in static scenes shooting from an angle, etc. - this is mostly the luck of the draw in my experience
* eyeAF in dynamic scenes (esp. close rapid movement towards the camera) - this is where both the camera and the AF motors in the lens play a big role (and where 85DN struggles)...
I also read Don's comments differently. I saw him saying the new 85 GM II wasn't better at capturing kid's eyes than the Sigma DG DN and both struggled. If anything the Sigma "might" have been better, but it "might" have been luck of the draw. That sounds to me exactly what I would expect if the AF performance was limited by the camera rather than the lens, and it fits with other reports that the new 85 GM II is clearly better than the Sigma DG DN with a top level camera like the A9 III.
I think we need to await more systematic tests and that is hard with AF, but over time I still expect that at least when you really push the AF system the new 85 GM II with its 4 super fast motors moving two different groups (as I understand it) is really going to provide outstanding AF. I say that as someone who isn't going to buy the lens and who recently picked up an 85 GM I. I will be very surprised if exceptional AF isn't one of the clear advantages of the GM II over both the first version and the Sigma DG DN. One things we know for sure, both the first version of the GM and the Sigma are going to be a lot more limited in frames per second than the new lens and that will matter for some, but obviously only those who have cameras that can take advantage of that ability for higher frames per second (i.e., it won't matter on an A7 IV or A7r V that can only do 10 fps). I think we will find a similar things for general AF performance as well. The better AF will be a much better benefit on newer cameras with more advanced AF performance.
Yes, I also had the same expectations regarding AF.
... but if you need A9III to make use of it in a non-extreme scenarios like kids running around the playground, I can't say it's what I expected...
But that is just the point: there is zero evidence you need an A9 III, just evidence that an A7 IV might not be enough. An A9 III seems to be enough, but I think it is likely that all the cameras that Guy mentioned here (https://www.fredmiranda.com/forum/topic/1871097/11#16643573) will be more than enough to get the benefits of the better AF from this new 85 GM II and I won't change my expectations until I see evidence that those cameras don't gain much by using the lens.
Well, my point is that A7IV should be enough for that scenario...
It's also possible it was a defective copy, due to that audible AF sound which I think no reviewer has mentioned...
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