Sony A1 A1 bird eye AF - does it add anything?

Ziggy

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I studied some vids that covered bird eye AF (BEAF). Details below. I've generalised from what they show and in time this may be superseded by new information.

First, what would I want from it or what problem should it solve?

The key one is getting focus on the head with a bird that's fairly large in the frame and flying at you or flying side on, so that it's the eye and not the wing that gets the lock.

None of these vids test that.

A second one: ordinary Small Spot AF is unreliable on small perched birds with the A9, A7R III and A7R IV. BEAF appears to do better but it's not instant.

There are 3 examples of birds in flight in the vids and in one it worked - a panning shot of a gull in good light.

With cormorants moving around on their feet in good light it worked. With a water fowl paddling along with a dark eye in a dark face it failed.

The surprise is that it worked with over-the-shoulder shots: a static bird with a small eye visible on a head pointing away from the camera. I would rarely keep a shot of this kind of pose so it offers no benefit to me.

Where it's likely to work promptly is where there's clear view of the eye in good light or with a catchlight in the eye. If there's a closer branch or frond in the Zone AF area it gets there eventually.

You want Zone AF for composition but it's slow to distinguish the bird's head from a nearer branch or frond. Touch AF or focus and recompose work better.

BEAF works better when you get a limited AF area over the head, but then you lose the composition advantage of Zone AF, and ordinary AF can be made to work in this case anyway.

Alex Phan got some brief tracking moments, one of them an error, and maybe the others weren't trying but so far there's little evidence that BEAF tracks.

My conclusion with this amount of information is that the only surprise is over-the-shoulder shots. Whether BAEF deals with BIF at all well is unclear and more tests are needed to come to a conclusion.


Details


Christopher Dodds
Promising but with a perched bird, focus jumped from eye to shoulder

DPRreview in fairly dull light
Static bird: constantly jumps between eye and feathers. You have to start with the AF area on the eye.

Alex Phan
Has good light; birds at a distance mostly with contrasting eye and face it does well but you don't need eye AF for those anyway.
Cormorants moving on their feet: got eye lock and briefly tracking.
Panning sequence of gull IF, got it sometimes.
In the first still Osprey sequence which is relatively close - when AF is on the head it mostly locks on the black band on the face.
In the Osprey nest sequence with a still bird square-on it gets a lock but not tracking and that's lost when the bird takes off.
Perched Peregrine: did well to get a lock from the rear, and tracking once on the eye from the rear and once a shoulder.

Julia Trotti
Got an eye lock on a static Galah but lost it when the bird took off. On and off on a perched Kookaburra (eye in shadow).

fototrainer
No BIF.
Grooming duck from rear: got beak or shoulder but with a clear side-on view of the head, got a lock. 2nd such view it failed for a bit then locked. 3rd rear view it got the tail then the head.
Robin: focused in without boxes.
Grey bird behind branch, side-on: took some time. Then lost it. Then got it (with Spot?).
Gold, white and black bird in shadows (dark eye in dark face) but no obstruction: got it.
Side-on grey and orange Robin? got it. Lost to twig. Regained. Clear eye contrast in face.
Same bird 3/4 view pointed away , got it.
Bird looking forward and down: failed.
On the ground, forward looking: took a second but got there.
On ground side-on: fine.
On ground, forward 3/4s, took a sec and locked. Lost but regained when bird bobbed to eat.
Bird turned 3/4 away and small box shrank and locked on the sliver of eye visible.
Dusky Moorhen (?) moving side-on: kept centering and losing it.
Quality: locks were usually sharp

James Gan
Over the shoulder of a shivering bird got a lock.

Kingfisher
Looks good but an f8 DOF with this size bird on a stick will capture a head anyway.
 
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Brilliant summary Ern! Maybe Sony needs to release a bird compatibility chart! :) I'm not sure if anyone is actually reporting how many keepers they are getting when the BEAF appears to be locking on to the eye, this would be useful as I'm sure there will be some variation between what the camera is showing and where the actual focus point lands. For most of my BIF I'm rarely close enough to worry too much about depth of field and I don't recall dumping too many shots where only the wing tip as been in focus. It's still an interesting development and I'm sure it will help to sell a lot of cameras, but it's definitely not a game changer and the instances where this is useful will be limited.
 
Thanks Tim.

Yeah, I'm often in f8 or so for BIF and the DoF takes care of that problem. But I'm also convinced that ordinary AF on the A9 in Zone has some smarts that preference the head.
 
Yes, I definitely awaiting more results from wildlife photographers but was pleasantly impressed with Alex's video testing especially as he's using the 200-600mm. 0f course here in the UK good light is usually our main problem but I am optimistic that the BEAF (another new acronym to add to the dictionary?) will be a great benefit to us wildlife shooters with the likelihood of future improvements.
 
The only sequence of Alex's that couldn't be readily achieved with existing means is the Peregrine Falcon. It rates as a record shot in which a sharp eye doesn't matter.
Added: should also say that the BLBS (blurry little bird syndrome) is looking improved with the A1. See fototrainer's vid on this.
 
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Ryan Mense adds a bit to what we know.
BEAF he says helps with small birds but he doesn't show a static one. He observes that it's 'hungry' for a bird's head and has some memory and those are a plus.
He doesn't test it with a BIF.
He found it didn't work in video.
He says that 30 fps only works with Release Priority, not AF priority. The A9 and A7R III accept soft shots in Release Priority. My A9 when set to 10 fps will drop to 3 fps with a BIF against a textured background.
If the A1 is similar, 30 fps will produce a shitload of culling work.

 
One of the tests of AF performance with birds is head-on shots of a BIF.

This is what an A9 can achieve, and it's not a one-off:

Red-rumped Parrot IF Janefield (89).jpg
  • ILCE-9
  • FE 100-400mm F4.5-5.6 GM OSS + 1.4X Teleconverter
  • 560.0 mm
  • ƒ/8
  • 1/2000 sec
  • ISO 5000


It's not as sharp as it could be since the camera was set for a static shot (1/1600s) when the bird took off.

And this one ...

Welcome Swallows WTP (22).jpg
  • NIKON D500
  • 500.0 mm
  • ƒ/8
  • 10/30000 sec
  • ISO 1100


which is taken with a Nikon D500 (and a Nikon consumer zoom) whose AF I find is better all-round than the A9's though it's harder to master.
 
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thanks. the youtube reviews are a nice distraction while i wait for mine to arrive on the 4th the 9th someday in march. i hope.
 
Alex Phan's promising test of a BIF

 
I shot nearly 2000 images today, all birds and all with Bird Eye AF, from a tiny phoebe to short-eared and snowy owl. I was very pleased with the AF and I'll say it hit the eye many more times than I would have expected, especially with small dark birds small in the frame. Of course this guy was easy as cake!:)
Snowy_0213.jpg
  • ILCE-1
  • FE 200-600mm F5.6-6.3 G OSS
  • 600.0 mm
  • ƒ/9
  • 1/400 sec
  • ISO 800
 
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It looks like it works well, but I personally think it's a gimmick on any camera really. There is no real need for it IMO. If you are focussing on the head, the eye is going to be in focus.
 
Using Imaging Edge I took some screen shots showing the focus point. I never got an eye with short eared owl perched or in flight. It also struggled with male hooded merganser. But otherwise ... here are some examples.
 

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"Animal subjects' eye distinction ranges from that of a sheepdog to that of a mountain goat, and current AF systems are not able to discern all eyes. To quickly present a large variety of subjects to the camera for initial testing, I used photos of the subjects.

The a1 was very adept at selecting whitetailed deer, raccoon, black bear, red fox, bighorn sheep, mountain goat, mountain lion, cottontail rabbit, gray squirrel, goldendoodles and golden retriever eyes. The eyes of elk, brown bear, moose, and horses (brown, black, palamino), black rat snakes, and pronghorn proved more challenging for the a1, with the camera only sometimes selecting them.

With birds selected as the subject, turkey, cormorant, snowy egret, great egret, royal tern, great blue heron, Canada goose, ovenbird, little green heron, magpie, canvasback, American widgeon, and blue jay eyes were routinely selected (many of these birds have black eyes or large black pupils). Bald eagle, wood duck, common loon, roseate spoonbill, and cardinal eyes were challenging to the a1's eye AF

With human subjects selected, the camera was quite adept at selecting the eyes and switching to faces when adequate depth of field would cover the eyes."


 
Using Imaging Edge I took some screen shots showing the focus point. I never got an eye with short eared owl perched or in flight. It also struggled with male hooded merganser. But otherwise ... here are some examples.
According to Mark Gawler, Imaging Edge isn’t necessarily accurate about where the AF was positioned when the shot was taken.
 
I shot a sequence of images of a black kite flying almost directly toward me. I was forced to stop when it flew over my head. I shot 33 images with the drive mode set to 20fps (lossless compressed RAW), but with the setting to Balanced Emphasis (still learning the set up of this beast). Anyway, all 33 images are sharply focussed, whether that is due to Zone AF or BEAF, I am unsure - I had both enabled.

I am happy with the A1 - I would never have managed that sequence with the A7R4, nor the A9 II (because I won’t use lossy compressed).

I shot about 3000 images that day. I think the A1 is going to help the sales of hard disks :D
 
You lose a bit of recoverable shadow detail with lossy compressed which is no drama in my book. That's not where the action is.
 
It looks like it works well, but I personally think it's a gimmick on any camera really. There is no real need for it IMO. If you are focussing on the head, the eye is going to be in focus.
Not all the head is in focus, the eye is.
A1_21402-Archive_m.jpg
  • ILCE-1
  • Sony FE 200–600mm F5.6–6.3 G OSS (SEL200600G)
  • 600.0 mm
  • ƒ/6.3
  • 1/500 sec
  • ISO 200
 
And you can't get this with AF Spot Small?
 
And you can't get this with AF Spot Small?
Can but only if the bird is not moving (rare)
A1_21482-Archive.jpg
  • ILCE-1
  • Sony FE 200–600mm F5.6–6.3 G OSS (SEL200600G)
  • 600.0 mm
  • ƒ/6.3
  • 1/2000 sec
  • ISO 500


Only someone named Clark Kent would be able to pull the next shot using AF spot small
A1_21579-Archive.jpg
  • ILCE-1
  • Sony FE 200–600mm F5.6–6.3 G OSS (SEL200600G)
  • 385.0 mm
  • ƒ/6.3
  • 1/1250 sec
  • ISO 500
 
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Not all the head is in focus, the eye is.
View attachment 9909
Yes, and while that's ok, to show that it works on the eye, I can do that with centre focus, but I'd use a bigger DOF to keep all of the head in focus, especially on a static shot. Human eye on the RIV works on birds and animals with larger eyes like this.
 
This was taken with the old tech of a Nikon D500 and pinpoint focus at f5.6 and 750mm focal length equivalent. So the DOF is around 10mm. It was moving too.

Rufous Whistler and prey f (16)-1.jpg
  • NIKON D500
  • 500.0 mm
  • ƒ/5.6
  • 10/6400 sec
  • ISO 560
 
What % crop is this?
This is around 75% of the full frame, I was lying down flat on the ground for more than the past 0h30, Sun in my back, so the birds got accustommed to my presence and this one moved quite close. I don't recall if I was in APS-C mode or not (to get the 900mm reach). I usually export my non-client JPGs at 3240px short side wich amounts ~15mpx archive file (for 3:2 racio crops), so I don't care if I only have a 21mpx RAW file to start with.
 
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Well, it's not adding much that I can see. It may make it easier but six grand AUD pays for a lot of practice.
 
Dan Carr's test of bird eye AF:

good for small bird portraits, complete fail on swans, nothing on BIF.

So, I'm still seeing little that it adds.

 
From Dan Carr at Shutter Muse:
 
It looks like it works well, but I personally think it's a gimmick on any camera really. There is no real need for it IMO. If you are focusing on the head, the eye is going to be in focus.
Not all the head is in focus, the eye is.
True Afonso… but this bird is standing still allowing the BEAF plenty of time to work its algorithm calculation. And in BIF movement and lots of non-contrast background flying by, I go with Kev’s comment. I suspect BEAF is a very complex calculation in split-seconds time frame. Sometimes hits, other times it misses. Stationary birds likely much easier like in Afonso’s pic. I open DoF as Kev suggests.
.
 

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Please avoid repeat posts by reading the thread before posting
Afonso, obviously your comment was well intended to reduce clutter or redundancy on the forum, but I deem this minor violation by Sandy as frivolous, and not needing attention.

Perhaps you didn’t notice that Sandy is a brand-new member and likely not yet very versed in forum drill. I’ve been on forum seemingly like pre-Civil War and I’m still learning the drill. I think we should especially cut newcomers more slack in their efforts to fit-in and learn procedures.

In my view, Sandy was merely trying to offer some info ref the a1’s BEAF feature. And maybe she overlooked the list of entries earlier in thread. But I think it a little harsh to flag a newcomer with less than 3 posts to their name. And sometimes it’s not carelessness, but rather some people don’t have the time to read through lengthy threads.

Hopefully, we try our best to be delicate with our advice or criticism, and remember that we’re here to offer help and promote membership and good will amongst our membership. Your admonishment could have been better handled through a PM to save any possible embarrassment to new members; or old members even.

And yes, perhaps I should have sent this by PM. But I think it’s a good reminder to all us (me included) to be careful in our commentaries, especially to newcomers. After all, Tim gets a $1,000 from Sony for every new member signing up on this forum…. Well… maybe not. :rolleyes:
 
Today I had a few spectacular BEAF fails. The camera locked onto a leaf/straw and would not let go of it.
A1_26265-Web.jpg
  • ILCE-1
  • Sony FE 200–600mm F5.6–6.3 G OSS (SEL200600G)
  • 600.0 mm
  • ƒ/6.3
  • 1/1600 sec
  • ISO 1000


Strange because in similar conditions it mostly works without issues.
A1_26074-Archive_m.jpg
  • ILCE-1
  • Sony FE 200–600mm F5.6–6.3 G OSS (SEL200600G)
  • 600.0 mm
  • ƒ/6.3
  • 1/1600 sec
  • ISO 500

A1_25923-Web.jpg
  • ILCE-1
  • Sony FE 200–600mm F5.6–6.3 G OSS (SEL200600G)
  • 600.0 mm
  • ƒ/6.3
  • 1/1600 sec
  • ISO 320
A1_26393-Web.jpg
  • ILCE-1
  • Sony FE 200–600mm F5.6–6.3 G OSS (SEL200600G)
  • 600.0 mm
  • ƒ/6.3
  • 1/1600 sec
  • ISO 640
A1_26686-Web.jpg
  • ILCE-1
  • Sony FE 200–600mm F5.6–6.3 G OSS (SEL200600G)
  • 600.0 mm
  • ƒ/6.3
  • 1/1600 sec
  • ISO 160
A1_26735-Web.jpg
  • ILCE-1
  • Sony FE 200–600mm F5.6–6.3 G OSS (SEL200600G)
  • 600.0 mm
  • ƒ/6.3
  • 1/1600 sec
  • ISO 160
 
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