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

[Ziggy]

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 I've generalised from what they show and in time this may be superseded by new information.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

Sony a1 review — Nature Photography Blog

I have spent a week immersing myself in the wonder of the new Sony Alpha 1 digital mirrorless camera from the perspective of a bird/wildlife/nature photographer. If you want the quick and easy answer from the end of the review: This is the best action, birds-in-flight, and all-around digital camer

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

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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.

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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).

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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

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

2.7K views · 99 reactions | “Sony A1” Peregrine Falcon Singapore 🇸🇬 #SonyBirdEyeTracking “spot on” on the peregrine falcon! It has sleepy eyes, almost closed, I can’t even see it.... | By James Gan | Facebook

“Sony A1” Peregrine Falcon Singapore 🇸🇬 #SonyBirdEyeTracking “spot on” on the peregrine falcon! It has sleepy eyes, almost closed, I can’t even see it....

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Kingfisher
Looks good but an f8 DOF with this size bird on a stick will capture a head anyway.

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[garuda]

In image #2 --- how did you get the sparrows to play hopscotch in front of the camera? Are they drama students?

I occasionally have same problem w 7R iv -- regardless of whether AF-lock set to "sticky" or not.

 

[Uncle Kevriano]

The above is why I advocate centre focus.

 

[Paul stuart]

Today I had a few spectacular BEAF fails. The camera locked onto a leaf/straw and would not let go of it.
View attachment 10176

Strange because in similar conditions it mostly works without issues.
View attachment 10181
View attachment 10177View attachment 10178View attachment 10179View attachment 10180

Question is do you want to be in control ,or are you happy with sony AI algorithms taking charge .

 

[Ziggy]

Bird eye AF?

Nope. Not even tracking. And this was at f4 and quite close.

• ILCE-7RM3
• FE 400mm F2.8 GM OSS + 1.4X Teleconverter
• 560.0 mm
• ƒ/4
• 1/1500 sec
• ISO 8000

 

[Ziggy]

Question is do you want to be in control ,or are you happy with sony AI algorithms taking charge .

It's a good question but it's not either/or. There's a pile of decisions made in software by the camera that we can't control and in some cases don't even know about. Eg. CDAF. In the photo above, I'm convinced the A7R III was making decisions between the eye/body and the wingtip.
It's a question of whether the algorithms can do better than we can (and are we expert or novice?), with what subjects in what circumstances.

 

[Doug Herr]

In my experience using the a1 for about three months now, the Bird Eye AF isn't 100% perfect but it's quite good. It will follow most hummingbirds' flight and stay locked onto the eye, struggling only with a dark eye against dark plumage in difficult light. Bird Eye AF often also finds the bird in dense brush and locks onto the eye even when the eye is partially obscured. I have a button set for wide area with bird eye AF and often all I need to do is press the button. The camera finds the bird, finds the eye and sticks to it even as the bird hops around in the brush or turns its head to momentarily hide the eye. Definitely not a gimmick.

 

[garuda]

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.

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In my experience using the a1 for about three months now, the Bird Eye AF isn't 100% perfect but it's quite good...... Definitely not a gimmick.

I probably shouldn’t be trying to interpret the meaning of another’s opinion. But for me his meaning was likely that Sony invents these more precise functions (BEAF) to entice customers to buy a more advanced camera based on an otherwise small feature like BEAF (when compared to more major improvements). When in fact, having the head in focus encompasses the eye in focus also.

If this BEAF feature vastly improves the speed and accuracy of target acquisition, then perhaps it may appeal to a significant number of alpha shooters and cam prospectors. Personally, I like DoF wider instead of having only the eye in perfect focus while the focus falls off increasing as pixels diverge from the extremely thin focal point/plane, especially at or near the f/1.4-1.8 setting.

I took the poster’s comments (gimmick) to mean just another advanced “selling” feature to nudge customers a bit more, when the GAS bug bites them. I think we all know BEAF can work when conditions are favorable AND when cam settings are conducive to the conditions at hand. But to me, any device or feature that works the majority of the time (51-100%) is a gimmick. When you slide the “ON” lever clockwise, power is supplied to camera 100% of the time, that’s a factual feature, not a gimmick.

[Merriam-Webster Dictionary--- gimmick: a trick or device used to attract business or attention; ie. a marketing gimmick.]
To sell cams beyond your competition, it’s likely prudent to have gimmicky flavors that appeal to the palate of the self-prescribed seeker of cutting-edge technology. And the question I ask myself is, does the extra money justified for these either factual or gimmicky features if they are of little real benefit to my shooting style.

 

[Uncle Kevriano]

So, the way I see it with the Eye AF, is that yes, it's looking for a specific shape to lock onto, but I think it may be slightly faster still if it were just looking for any part of your subject to lock onto. I do not question that it's impressive, and very clever, and definitely appeals to a great many, but I've been shooting for 40 ears and never had it in the past, and have always managed birds in flight without. I would even say that my old Minolta 700si was as good as anything now at acquiring focus on a flying bird. I didn't miss many!

 

[Ziggy]

What the A9 and A7Rs are not good at is locking onto a small static bird. Doug's experience appears to indicate that the A1 does better. That would be down to software and processing power.
That's available only to a few. My advice to beginning bird shooters is to get a Nikon D500 or maybe Canon 7D Mk II.
THE D500 is harder to learn than the A9 but the AF is more reliable and accurate. There's young cheap units aplenty 2nd hand.

 

[Uncle Kevriano]

What the A9 and A7Rs are not good at is locking onto a small static bird. Doug's experience appears to indicate that the A1 does better. That would be down to software and processing power.
That's available only to a few. My advice to beginning bird shooters is to get a Nikon D500 or maybe Canon 7D Mk II.
THE D500 is harder to learn than the A9 but the AF is more reliable and accurate. There's young cheap units aplenty 2nd hand.

The A7RIV is perfectly fine at locking on to small static birds etc. (Just look at my Butterfly post), so much is down to people using totally the wrong focus mode. Use anything other than single centre and the AF will look around for anything to focus on. I have tried them all, nothing works better than single centre, because you have total control of where it's aimed.

 

[Ziggy]

I've tracked this issue across multiple forums (Fred Miranda, DPreview, Feathers and Photos, FB) and extensively used the A9 and A7R III that clearly use similar algorithms. On-sensor PD gets confused regularly by small static birds.

The term 'confused' is used by the local Nikon/Sony/Canon service agent.

Note that I didn't say it can't function but that it's not reliable. Focus racks out but no AF point is recorded in EXIF.

Sony AF weaknesses - A9, A7R III

https://m.facebook.com/groups/sonya9/permalink/2606391359453112/

 

[Doug Herr]

I've tracked this issue across multiple forums (Fred Miranda, DPreview, Feathers and Photos, FB) and extensively used the A9 and A7R III that clearly use similar algorithms. On-sensor PD gets confused regularly by small static birds.

The term 'confused' is used by the local Nikon/Sony/Canon service agent.

Note that I didn't say it can't function but that it's not reliable. Focus racks out but no AF point is recorded in EXIF.

Sony AF weaknesses - A9, A7R III

https://m.facebook.com/groups/sonya9/permalink/2606391359453112/

Tracking the issue on internet forums and using the camera are two very different things. Likewise tracking the issue with the a9 and a7rIII and extrapolating to the a1 is quite foolish. This isn't anywhere near my experience with the a1. The a1 reliably finds the bird and locks onto the eye; it can be a small static distant bird, or a bird partially obscured in the brush, or perched on a very detailed high-contrast tree trunk, or the erratic flight of a hummingbird.

And no, DOF does not get the eye in focus if "the head" is in focus. DOF at close range for a small bird is negligible; only part of the head will be in focus. The a1 does struggle with a fast erratic tiny bird at close range in poor light with a dark eye and dark plumage (example below) but the struggle is relative: the vast majority of the time it locks onto the eye in less than a second in this scenario. The a1 with bird eye AF enabled has easily been the most productive camera I've ever used for bird photos.

• ILCE-1
• Sony FE 600mm F4 GM OSS (SEL600F40GM)
• 600.0 mm
• ƒ/5.6
• 1/1000 sec
• ISO 2000

 

[Doug Herr]

So, the way I see it with the Eye AF, is that yes, it's looking for a specific shape to lock onto, but I think it may be slightly faster still if it were just looking for any part of your subject to lock onto. I do not question that it's impressive, and very clever, and definitely appeals to a great many, but I've been shooting for 40 ears and never had it in the past, and have always managed birds in flight without. I would even say that my old Minolta 700si was as good as anything now at acquiring focus on a flying bird. I didn't miss many!

The bird Eye AF first finds the bird, then finds the bird's eye. I've been photographing birds for 50 years and the a1 with bird eye AF enabled is by far the most productive camera I've ever used.

 

[Ziggy]

Tracking the issue on internet forums and using the camera are two very different things.

I was doing both - the first in order to make sense of a weakness I found on first and continued use of the A9 and then the A7R III. I found plenty of others had had the same experience, including with the A7R IV.

Likewise tracking the issue with the a9 and a7rIII and extrapolating to the a1 is quite foolish.

If you took the care to read the posts, you'll see I was responding to Kevriano's generalisation about the A7R IV. One swallow does not a spring make; one success doesn't equal reliable performance. I can get a string of successes followed by a string of failures.
That's the problem with the bodies I was referring to. They're not reliable in this use case so they can't be recommended for those taking record shots. They're fine for BIF if still not quite as accurate as the best module PD.

 

[garuda]

.... A7Rs are not good at is locking onto a small static bird....

My consistent experience w 7Riv is: simply place target at center and hold down AF-ON button. Totally locks-on quickly, especially w 135GM. Then I can (and do) move the FoV to where I want the target to appear (1/3s) in the frame. For my settings, it works consistently whether mode is Wide or SmCtr. I have difficulties understanding arguments contrary to this (at least for Riv's -- don't know a9s).

.... Doug's experience appears to indicate that the A1 does better....

Obviously it has been shown that the a1 is better in many areas (at least somewhat in several, much better in others). But to claim a1 does the AF Lock-on better than R7iv --- I hope they mean in terms of speed of acquisition only. Because to me, it either works or it doesn't, in terms of locking on. When my AF-ON locks-on (in milli-secs) it won't let go, so long as locked-target stays in FoV regardless of mode, and I shoot a lot of Wide. On acquisition speed, the a1 may have an edge. But for Lock-on specifically, 7Riv is like the proverbial steel-trap, at least in my experience.... consistently. And it doesn't matter whether it's a small stationary bird or a low-flying Pterodactyl.

 

[Ziggy]

And no, DOF does not get the eye in focus if "the head" is in focus. DOF at close range for a small bird is negligible; only part of the head will be in focus.

It may, it may not, it depends on the circumstances.

All of photography depends on the zone of acceptable sharpness (aka DOF). There is only one plane that will be in focus but there's an area in front and behind it that the eye (and the sensor) can't register blur in.

I wasn't talking about close range. You've added this as a condition. The AF failures people experience are in mid ground or further.

 

[garuda]

And no, DOF does not get the eye in focus if "the head" is in focus. DOF at close range for a small bird is negligible; only part of the head will be in focus.

I shot this today at 600mm, at 8 feet from Wren house (to test your theory stated above). And I used a low DoF to make my point (6.3 vs 11). It seems to me that both the head and eye are in focus to about the same degree. Maybe not perfect since I'm using a cheaper camera. And the bird it stationary at close range. Same shot, I cropped closer and closer for subsequent images.

I focused on head, not eye -- yet both seem the same focus. In fact, the entire bird seems in fairly good focus. You be the judge. And I invite harsh criticism if my images are not supporting my earlier statements.

• ILCE-7RM4
• 600.0 mm
• ƒ/6.3
• 1/80 sec
• ISO 160

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• ILCE-7RM4
• 600.0 mm
• ƒ/6.3
• 1/80 sec
• ISO 160

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• ILCE-7RM4
• 600.0 mm
• ƒ/6.3
• 1/80 sec
• ISO 160

 

[Doug Herr]

I shot this today at 600mm, at 8 feet from Wren house (to test your theory stated above). And I used a low DoF to make my point (6.3 vs 11). It seems to me that both the head and eye are in focus to about the same degree. Maybe not perfect since I'm using a cheaper camera. And the bird it stationary at close range. Same shot, I cropped closer and closer for subsequent images.

I focused on head, not eye -- yet both seem the same focus. In fact, the entire bird seems in fairly good focus. You be the judge. And I invite harsh criticism if my images are not supporting my earlier statements.

View attachment 10523

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View attachment 10524
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View attachment 10525

It looks like it was processed a lot, i.e., over-processed. Also the cheek feathers, near side of the eye and the bill are not in focus. IMHO this photo does not demonstrate the full capabilities of your camera.

 

[Doug Herr]

It may, it may not, it depends on the circumstances.

All of photography depends on the zone of acceptable sharpness (aka DOF). There is only one plane that will be in focus but there's an area in front and behind it that the eye (and the sensor) can't register blur in.

I wasn't talking about close range. You've added this as a condition. The AF failures people experience are in mid ground or further.

I haven't see the AF failures at mid-ground or further. In fact I've been favorably impressed with the camera's selection of the bird at distance.

 

[Ziggy]

I haven't see the AF failures at mid-ground or further. In fact I've been favorably impressed with the camera's selection of the bird at distance.

You haven't bothered to look at the links I posted.
Head, sand.
Welcome to my ignore list.

 

[Doug Herr]

Welcome to my ignore list.

Thank you! Please do the same on other forums. I'll gladly reciprocate.

 

[garuda]

It looks like it was processed a lot, i.e., over-processed. Also the cheek feathers, near side of the eye and the bill are not in focus. IMHO this photo does not demonstrate the full capabilities of your camera.

Grab a beer, another long one you hate reading:

Actually, I agree with you on one item, that is, the photo does not demonstrate the full potential of the 7Riv. It was hot today with no nearby shade, and I spent a short amount of time trying to freeze this quick-moving rascal feeding her hatchlings. And I wasn’t interested in capturing the perfectly focused image. But rather catching the bird stationary at a 90-degree angle to lens hoping to get the eye and head on nearly the same focal plane in order to determine your claim: “DOF does not get the eye in focus if "the head" is in focus.” And that’s all.

Sweltering heat prevented me from patiently waiting for the perfect AF when at perpendicular to lens. And for comparison purposes only (not for aesthetics’ sake), I did remove some noise and bumped the sharpness a bit to reduce blur enough to do the comparison between sharpness of eye compared to sharpness of head. It falls under the forensic umbrella for more accurate analysis.

And after inviting criticism, I’m surprised you didn’t notice that the entire bird is out-of-focus, not just the cheek and bill. But that’s not the point of this comparison. It was confined to your claim in testing whether the eye is in focus when the head is in focus. My conclusion is that both the head and eye are nearly equally out-of-focus.

Whether image is extremely blurry or pin-point sharp is beside the point. It’s the focal quantity comparison betw eye and head (based on your claim). But I compliment you on your skill at “misdirection” or “issue avoidance” by shifting attention away from the real substance of the issue or claim.

It’s beating a dead horse to argue this any further. You may be correct in your claim, but it was foolish of me to present any challenge regarding a point I could really care less about. Whether rightly or wrongly, I still believe the AF algorithms can acquire the head faster than the eye, so I use the best DoF for nailing the head. And if it is any consolation, I feel like an idiot for arguing this issue since the 7Riv doesn’t have BEAF and I don’t own an a1. What was I thinking? The brain must get soft being out there in the blazing sun.

I thought I had rid myself of the legitimate title “village idiot"…. but maybe not.

 

[Ziggy]

I'm happy to engage with people with informed opinions. Not fanboys.