IBIS Fractures ? Is that a thing ?

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Kumsa
Kumsa Contributing Member • Posts: 623
IBIS Fractures ? Is that a thing ?

In the latest LensRentals teardown by Roger Cicala , he makes an off-handed comment that "we’ve started becoming aware of fractures in IBIS units."

Wow. That is really something I hadn't considered, and clearly would be important for (1) evaluating the expected use of equipment, and (2) for buying used. For example, in one of Roger's podcasts on used equipment, the topic turns to used lenses, and now I'll think twice before laying down a lot of money for an IS stabilized, auto-focus fast lens.

Any experience on IBIS fractures (I'm assuming on the sensor) ?

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sybersitizen Forum Pro • Posts: 18,048
Re: IBIS Fractures ? Is that a thing ?

Kumsa wrote:

In the latest LensRentals teardown by Roger Cicala , he makes an off-handed comment that "we’ve started becoming aware of fractures in IBIS units."

Any experience on IBIS fractures (I'm assuming on the sensor) ?

He started the whole thing himself a couple of months ago.

That stirred up an ants' nest here at the time, and the new post will probably do it again.

onlyfreeman
onlyfreeman Senior Member • Posts: 2,309
Re: IBIS Fractures ? Is that a thing ?
1

I think it's just a Sony thing and probably quite rare too.

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Jestertheclown
Jestertheclown Senior Member • Posts: 2,847
Re: IBIS Fractures ? Is that a thing ?
1

Kumsa wrote:

In the latest LensRentals teardown by Roger Cicala , he makes an off-handed comment that "we’ve started becoming aware of fractures in IBIS units."

Wow. That is really something I hadn't considered, and clearly would be important for (1) evaluating the expected use of equipment, and (2) for buying used. For example, in one of Roger's podcasts on used equipment, the topic turns to used lenses, and now I'll think twice before laying down a lot of money for an IS stabilized, auto-focus fast lens.

Any experience on IBIS fractures (I'm assuming on the sensor) ?

Have a look at this.

I questioned this a couple of months back, at which time, I was about to buy a Sony A7RIII.

As you can see, I got plenty of response, mostly, unsurprisingly, unpleasant but if you're in the market for a camera that just might be affected, it's probably worth reading.

Incidentally, shortly after I abandoned that thread, I bought a Nikon Z7 and haven't looked back.

"It's good to be . . . . . . . . . Me!"

Antisthenes Regular Member • Posts: 364
Not really an issue for most users, IMHO
1

I love Roger Cicala's articles, but I often have to roll my eyes when he ponders some design aspect of a lens or camera. I definitely wouldn't hold that against him, because Roger's background is in medical science, and the fact that he's got no specialist knowledge in physics, optics, mechanical or electrical engineering or software design is quite understandable.

As a recent example, I skimmed through the teardown of a saltwater-damaged Fuji GFX100, and couldn't help notice a couple of amusing conjectures:

(a) that the electrical connection to the first glass plate might be there to create some electrical charge on said glass plate

(b) that the springs attached to the IBIS mechanism might allow for some "vertical" movement, as this is a 5-axis IBIS system

Conjecture (a) makes one realize that Roger isn't familiar with, or hasn't internalized the fact that many interchangeable-lens digital cameras have dust shakers in front of the imaging sensor. The electrical conductor simply powers the thin piezoelectric ceramic vibrating strip attached to the first layer of glass.

Conjecture (b) makes one realize that Roger might be thinking that IBIS needs to tilt the sensor, which is absolutely false. Every camera shake motion compensated of a 5-axis IBIS is, ultimately, mapped to translation movements of the sensor, not to a tilt. Tilting the sensor relative to the lens' optical axis would cause a tilting of the plane of focus — as per Scheimpflug's principle — and possibly cause large areas of the picture to go out of focus.

To prevent the occurrence of any tilt, the sensor is supported by three tiny ceramic balls, kept sandwiched between the sensor plate and the base plate by multiple tensioning springs.

Let's also note that the "Halbach" magnet disposition above the IBIS electromagnetic coils can create only lateral Laplace forces — i.e. forces that are perpendicular to the plane of the solenoid. Therefore, the sensor plate can only "slide" in a parallel fashion relative to the base plate, the direction of that movement being regulated by the IBIS controller simply by changing the polarity of the current circulating in the coils.

In another teardown — of Nikon's latest 120-300mm lens — I seem to remember Roger conjectured that some unmarked, smallish and fairly thick rectangular component on the PCB of a function button (high-end telephoto lenses often have programmable buttons around the lens barrel) might be a memory device. The component doesn't look at all like an electronic chip — some people might need to be reminded that a memory device is an electronic chip, after all. I'm a bit amused that the width and layout of the electrical traces leading to that mysterious component, and the Nikon lens' functionalities, didn't immediately suggest to Roger that the component was a buzzer designed to produce the confirmation beeps the lens emits when the buttons are operated.

Basically, an inability to properly integrate into his thinking the facts that

  • a memory device has no place in such an area
  • a chip wouldn't look like that at all
  • the lens requires some way to emit beep sounds

making him unable to reach plausible engineering hypotheses (buzzer, instead of memory chip)

But, I repeat, I love Roger's articles, as they are quite unique on the Internet, nice to read and very informative, despite the occasional eye rolling and pinches of salt (not necessarily supplied by seawater) they might require.

Anyway, for the IBIS fracturing on Sony's cameras, I seem to remember Roger being surprised that a "cracked" frame didn't result in visible impact on a camera's imaging performance.

Roger seems to overlook the fact that the reference surface of an interchangeable-lens camera, for optical alignment purposes, is the lens mount. Everything — the flangeback distance, the tilt, the centering — derives from the "zero" point defined by the mounting flange on the camera body.

On mirrorless cameras, designers would thus ensure that a sensor — be it packaged in an IBIS block or not — is mounted as precisely as possible relative to the lens mount, using e.g. accurately shimming. The mount+sensor form a precisely adjusted, single block, "floating", in some sense, inside the camera's body — the outer shell.

That concept of "floating" inside the body might be difficult to mentally picture.
This visual example might give an idea of how a mechanical block requiring precise optical alignment is solidly attached to the reference mount surface, and "floats" inside the camera body:

What I suspect Roger saw were cracks on the less critical, spacing attachments between the body shell and the "floating" mount+sensor assembly. Therefore, it's not surprising at all that even if the body shell becomes slightly ajar relative to the mount+sensor assembly, the critical optical parameters (distance/tilt/alignment) between the reference mount surface and the sensor — and therefore, the image quality / focusing performance etc. — aren't much affected.

What could cause such fracturing between the body and the mount+sensor block ?

Some Sony A7 models might have been rented by people who have Nikon or Canon SLRs, and who wanted to test how a FF mirrorless camera would perform with their SLR lenses using a mount adapter.

A risk there, for Nikon users, is that their muscle memory — developed over years of using Nikon cameras — might induce them to try to rotate their well-known Nikon lens in the familiar direction (which happens to be wrong from a Sony body perspective) when trying to unmount the lens.

As the lens wouldn't budge, such users might just try to apply additional force, still in the wrong rotational direction. The resulting torque and large torsional stress might rotate / bend the Sony A7's body shell relative to its mount+sensor block, and the spacers between the body shell and the mount+sensor block might thus get fractured.

The above is, of course, pure speculation of my part, only based on my observation of some long-time Nikon camera users, but I have no otherwise reasonable explanation about the origin of mechanical stresses sufficient to crack the (not that critical) supporting / spacer attachments between a body shell and a mount+sensor block.

57even Forum Pro • Posts: 14,783
Re: Not really an issue for most users, IMHO
4

Antisthenes wrote:

The above is, of course, pure speculation of my part, only based on my observation of some long-time Nikon camera users, but I have no otherwise reasonable explanation about the origin of mechanical stresses sufficient to crack the (not that critical) supporting / spacer attachments between a body shell and a mount+sensor block.

You could always look it up...

https://petapixel.com/2020/06/12/lensrentals-flange-test-reveals-ibis-fractures-in-some-sony-cameras/

My experience of Sony cameras, though indirectly via some friends who traded Canon and Nikon DSLRs for Sony A series cameras, is that they are not as robust. Weak lens mounts was one example. This seems to be another.

Any vibrating system, especially one with any mass to it, is susceptible to stress fractures if not properly engineered.

I have had one camera replaced because an IBIS unit was faulty on purchase. When enabled, every image had noticeable motion blur and the sensor became increasingly misaligned with the camera.

When repaired, the camera only smeared images at 1/30, 1/60 and 1/120 of a second.

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Antisthenes Regular Member • Posts: 364
Re: Not really an issue for most users, IMHO
1

57even wrote:

Antisthenes wrote:

The above is, of course, pure speculation of my part, only based on my observation of some long-time Nikon camera users, but I have no otherwise reasonable explanation about the origin of mechanical stresses sufficient to crack the (not that critical) supporting / spacer attachments between a body shell and a mount+sensor block.

You could always look it up...

https://petapixel.com/2020/06/12/lensrentals-flange-test-reveals-ibis-fractures-in-some-sony-cameras/

My experience of Sony cameras, though indirectly via some friends who traded Canon and Nikon DSLRs for Sony A series cameras, is that they are not as robust. Weak lens mounts was one example. This seems to be another.

Any vibrating system, especially one with any mass to it, is susceptible to stress fractures if not properly engineered.

I have had one camera replaced because an IBIS unit was faulty on purchase. When enabled, every image had noticeable motion blur and the sensor became increasingly misaligned with the camera.

When repaired, the camera only smeared images at 1/30, 1/60 and 1/120 of a second.

In case it's not clear, I have actually read the article you linked to.

In case it's not actually clear, I also trust my level of actual experience and understanding of physics and engineering issues more than, say, LensRentals'.

57even Forum Pro • Posts: 14,783
Re: Not really an issue for most users, IMHO
6

Antisthenes wrote:

57even wrote:

Antisthenes wrote:

The above is, of course, pure speculation of my part, only based on my observation of some long-time Nikon camera users, but I have no otherwise reasonable explanation about the origin of mechanical stresses sufficient to crack the (not that critical) supporting / spacer attachments between a body shell and a mount+sensor block.

You could always look it up...

https://petapixel.com/2020/06/12/lensrentals-flange-test-reveals-ibis-fractures-in-some-sony-cameras/

My experience of Sony cameras, though indirectly via some friends who traded Canon and Nikon DSLRs for Sony A series cameras, is that they are not as robust. Weak lens mounts was one example. This seems to be another.

Any vibrating system, especially one with any mass to it, is susceptible to stress fractures if not properly engineered.

I have had one camera replaced because an IBIS unit was faulty on purchase. When enabled, every image had noticeable motion blur and the sensor became increasingly misaligned with the camera.

When repaired, the camera only smeared images at 1/30, 1/60 and 1/120 of a second.

In case it's not clear, I have actually read the article you linked to.

In case it's not actually clear, I also trust my level of actual experience and understanding of physics and engineering issues more than, say, LensRentals'.

And your 'understanding' of engineering and physics leads to conclude that it's all down to ham-fisted Nikon users? Very scientific of you.

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Antisthenes Regular Member • Posts: 364
Re: Not really an issue for most users, IMHO
1

57even wrote:

Antisthenes wrote:

57even wrote:

Antisthenes wrote:

The above is, of course, pure speculation of my part, only based on my observation of some long-time Nikon camera users, but I have no otherwise reasonable explanation about the origin of mechanical stresses sufficient to crack the (not that critical) supporting / spacer attachments between a body shell and a mount+sensor block.

You could always look it up...

https://petapixel.com/2020/06/12/lensrentals-flange-test-reveals-ibis-fractures-in-some-sony-cameras/

My experience of Sony cameras, though indirectly via some friends who traded Canon and Nikon DSLRs for Sony A series cameras, is that they are not as robust. Weak lens mounts was one example. This seems to be another.

Any vibrating system, especially one with any mass to it, is susceptible to stress fractures if not properly engineered.

I have had one camera replaced because an IBIS unit was faulty on purchase. When enabled, every image had noticeable motion blur and the sensor became increasingly misaligned with the camera.

When repaired, the camera only smeared images at 1/30, 1/60 and 1/120 of a second.

In case it's not clear, I have actually read the article you linked to.

In case it's not actually clear, I also trust my level of actual experience and understanding of physics and engineering issues more than, say, LensRentals'.

And your 'understanding' of engineering and physics leads to conclude that it's all down to ham-fisted Nikon users? Very scientific of you.

Reading comprehension is often also an issue with people who lack simple logical thinking abilities or the ability to engage in metacognition — the ability to think about their thinking, and whether they are able to realize at all that they don't even know that they don't know.

There's, well, a quite simple principle of physics that many people are ignorant of: it's the principle of "action and reaction".

People ignorant of physics, and of that principle of course won't understand where it applies.

A sensor board and its IBIS electrical coils weigh, at most, a few tens of grams.

An IBIS unit moves a sensor board over a range of a few millimeters at most. The mechanical force exerted by the IBIS unit to move a few tens of grams at most is thus quite small, in absolute terms. How small is it ? Well, small enough that a human, holding a lens that is rigidly attached to the lens+mount+sensor unit, won't be able to even perceive and detect the action+reaction force being generated while the IBIS is in operation.

On the other hand, would a human be able to detect the torsional force between a body shell and the mount+sensor unit that could cause the spacers between the body shell and the mount+sensor unit to fracture ? You bet a human could — that torsional force is, after all, one that can be actively developed by a human's musculature. The mechanical stress exerted on the spacing attachments between the body shell and the mount+sensor unit by human muscles trying to twist, say, a Nikon lens in the wrong direction while trying to unmount it will therefore be multiple orders of magnitude larger than the essentially imperceptible action+reaction force exerted by the IBIS on elements outside the rigid lens+mount+sensor ensemble inside which it's moving.

It's thus pure speculation of my part that twisting torque between the body shell and the lens mount caused by, say, human muscles might be involved, but it's not entirely illogical to consider, when trying to determine what might cause a linkage element to fracture, the origins and respective magnitudes of the forces that might be exerted on said elements.

Leonard Migliore
Leonard Migliore Forum Pro • Posts: 18,230
A word from the ham-fisted

57even wrote:

Antisthenes wrote:

57even wrote:

Antisthenes wrote:

The above is, of course, pure speculation of my part, only based on my observation of some long-time Nikon camera users, but I have no otherwise reasonable explanation about the origin of mechanical stresses sufficient to crack the (not that critical) supporting / spacer attachments between a body shell and a mount+sensor block.

You could always look it up...

https://petapixel.com/2020/06/12/lensrentals-flange-test-reveals-ibis-fractures-in-some-sony-cameras/

My experience of Sony cameras, though indirectly via some friends who traded Canon and Nikon DSLRs for Sony A series cameras, is that they are not as robust. Weak lens mounts was one example. This seems to be another.

Any vibrating system, especially one with any mass to it, is susceptible to stress fractures if not properly engineered.

I have had one camera replaced because an IBIS unit was faulty on purchase. When enabled, every image had noticeable motion blur and the sensor became increasingly misaligned with the camera.

When repaired, the camera only smeared images at 1/30, 1/60 and 1/120 of a second.

In case it's not clear, I have actually read the article you linked to.

In case it's not actually clear, I also trust my level of actual experience and understanding of physics and engineering issues more than, say, LensRentals'.

And your 'understanding' of engineering and physics leads to conclude that it's all down to ham-fisted Nikon users? Very scientific of you.

Well, we're pretty brutal folks. We can wreck anything that's not a Nikon.

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Leonard Migliore

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zxaar Veteran Member • Posts: 4,458
Re: Not really an issue for most users, IMHO

Antisthenes wrote:

I love Roger Cicala's articles, but I often have to roll my eyes when he ponders some design aspect of a lens or camera. I definitely wouldn't hold that against him, because Roger's background is in medical science, and the fact that he's got no specialist knowledge in physics, optics, mechanical or electrical engineering or software design is quite understandable..

yes very much.

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57even Forum Pro • Posts: 14,783
Re: Not really an issue for most users, IMHO
3

Antisthenes wrote:

57even wrote:

Antisthenes wrote:

57even wrote:

Antisthenes wrote:

The above is, of course, pure speculation of my part, only based on my observation of some long-time Nikon camera users, but I have no otherwise reasonable explanation about the origin of mechanical stresses sufficient to crack the (not that critical) supporting / spacer attachments between a body shell and a mount+sensor block.

You could always look it up...

https://petapixel.com/2020/06/12/lensrentals-flange-test-reveals-ibis-fractures-in-some-sony-cameras/

My experience of Sony cameras, though indirectly via some friends who traded Canon and Nikon DSLRs for Sony A series cameras, is that they are not as robust. Weak lens mounts was one example. This seems to be another.

Any vibrating system, especially one with any mass to it, is susceptible to stress fractures if not properly engineered.

I have had one camera replaced because an IBIS unit was faulty on purchase. When enabled, every image had noticeable motion blur and the sensor became increasingly misaligned with the camera.

When repaired, the camera only smeared images at 1/30, 1/60 and 1/120 of a second.

In case it's not clear, I have actually read the article you linked to.

In case it's not actually clear, I also trust my level of actual experience and understanding of physics and engineering issues more than, say, LensRentals'.

And your 'understanding' of engineering and physics leads to conclude that it's all down to ham-fisted Nikon users? Very scientific of you.

<<Patronising rant deleted for brevity>>

It's thus pure speculation of my part that twisting torque between the body shell and the lens mount caused by, say, human muscles might be involved, but it's not entirely illogical to consider, when trying to determine what might cause a linkage element to fracture, the origins and respective magnitudes of the forces that might be exerted on said elements.

For one thing, anyone twisting a lens hard enough to distort the body would almost certainly damage the lens mount and cause other issues, but that was not stated as a co-factor. In fact, fewer had mount issues than IBIS fractures.

Secondly, if you'd bothered to read further...

https://www.lensrentals.com/blog/2020/06/the-great-flange-to-sensor-distance-article-part-ii-photo-cameras/

You'd see that the fractured component was a plastic plate to which the sensor is mounted, which I would interpret to mean that it's part of the floating assembly, not the one mounted to the body. Hard to tell from these, but its clearly shown here...

https://www.youtube.com/watch?time_continue=8&v=-Ncye37e6xM&feature=emb_logo

In which case, it is part of the floating assembly and should be immune to torque stress on the rest of the body. And I'd like to see your muscles bend the cast metal parts of the IBIS assembly that it's mounted to.

I have no idea what the root cause is, but cracks in a plastic mounting may be due to misaligned holes, over-tightened screws, poor materials quality, or any number of things, which could lead to stress fractures developing.

And as for the forces involved, normally it would seem unlikely, but the plastic used appears quite brittle from the fracture line, so if a fault line was created during the assembly, it's not inconceivable that it would widen with movement and lead to failure. It's also possible it came from the factory like that.

The fact that a screw had actually sheared in one example does rather suggest an assembly error.

Perhaps you should look up Cognitive Dissonance and ask yourself why you are trying so hard to deny that it's a problem with (some) cameras and not with ham-fisted users.

And as for your kind lecture on high school physics, I have seen vibration stress in similar systems. Engineers seldom build anything stronger than it needs to be, and sometimes don't account for assembly variation, but if the system reaches the full extent of it's travel for any reason, the acceleration component at the bump stop can be quite high.

F = ma, which of course you know.

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57even Forum Pro • Posts: 14,783
Re: A word from the ham-fisted

Leonard Migliore wrote:

57even wrote:

Antisthenes wrote:

57even wrote:

Antisthenes wrote:

The above is, of course, pure speculation of my part, only based on my observation of some long-time Nikon camera users, but I have no otherwise reasonable explanation about the origin of mechanical stresses sufficient to crack the (not that critical) supporting / spacer attachments between a body shell and a mount+sensor block.

You could always look it up...

https://petapixel.com/2020/06/12/lensrentals-flange-test-reveals-ibis-fractures-in-some-sony-cameras/

My experience of Sony cameras, though indirectly via some friends who traded Canon and Nikon DSLRs for Sony A series cameras, is that they are not as robust. Weak lens mounts was one example. This seems to be another.

Any vibrating system, especially one with any mass to it, is susceptible to stress fractures if not properly engineered.

I have had one camera replaced because an IBIS unit was faulty on purchase. When enabled, every image had noticeable motion blur and the sensor became increasingly misaligned with the camera.

When repaired, the camera only smeared images at 1/30, 1/60 and 1/120 of a second.

In case it's not clear, I have actually read the article you linked to.

In case it's not actually clear, I also trust my level of actual experience and understanding of physics and engineering issues more than, say, LensRentals'.

And your 'understanding' of engineering and physics leads to conclude that it's all down to ham-fisted Nikon users? Very scientific of you.

Well, we're pretty brutal folks. We can wreck anything that's not a Nikon.

I managed to wreck a Nikon, but it was only a D90...

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Jestertheclown
Jestertheclown Senior Member • Posts: 2,847
Re: Not really an issue for most users, IMHO
1

Antisthenes wrote:

I love Roger Cicala's articles, but I often have to roll my eyes when he ponders some design aspect of a lens or camera. I definitely wouldn't hold that against him, because Roger's background is in medical science, and the fact that he's got no specialist knowledge in physics, optics, mechanical or electrical engineering or software design is quite understandable.

I'm sure he won't be offended . . .

Of course, and disregarding your twaddle, there's always the alternative explanation for these breakages; Sony used inferior (read cheap) parts/designs/applications and they've simply failed.

Roger just happened to highlight the fact.

It would be good to hear what Sony have to say about this.

Unless I've missed it, they're remaining remarkably quiet.

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Antisthenes Regular Member • Posts: 364
Re: Not really an issue for most users, IMHO
1

57even wrote:

Antisthenes wrote:

It's thus pure speculation of my part that twisting torque between the body shell and the lens mount caused by, say, human muscles might be involved, but it's not entirely illogical to consider, when trying to determine what might cause a linkage element to fracture, the origins and respective magnitudes of the forces that might be exerted on said elements.

For one thing, anyone twisting a lens hard enough to distort the body would almost certainly damage the lens mount and cause other issues, but that was not stated as a co-factor. In fact, fewer had mount issues than IBIS fractures.

The magnitude of the body flex induced e.g. by excessively muscular torsional forces doesn't have to be huge.

Let's compare the pictures from

https://www.lensrentals.com/blog/2020/06/the-great-flange-to-sensor-distance-article-part-ii-photo-cameras/

and the pictures from a Sony A7R2 teardown by iFixit.com:

https://www.ifixit.com/Teardown/Sony+a7R+II+Teardown/45597

A comparison with the known size of the active area of a "full-frame" image sensor — about 24x36mm — shows that the fractured positioning pin (indicated by a yellow arrow) protruding from the mobile support frame, presumably made of magnesium alloy, must have a diameter of circa 1.1 millimeters.

The lateral displacement of that fractured pin and of the frame-holding screw next to it, seems to be a fraction of a diameter of said fractured pin — i.e. a fraction of 1.1mm. We're talking maybe a 0.5mm lateral displacement, which isn't huge, and seems within range of the amplitude of a possible body flex.

The fractured (magnesium?) pin has a diameter of ca. 1mm, and hasn't moved very much laterally

Secondly, if you'd bothered to read further...

https://www.lensrentals.com/blog/2020/06/the-great-flange-to-sensor-distance-article-part-ii-photo-cameras/

You'd see that the fractured component was a plastic plate to which the sensor is mounted, which I would interpret to mean that it's part of the floating assembly, not the one mounted to the body.

Someone forcibly trying to twist a lens in the wrong direction will probably apply both a torsional shear force, and a compressive force on the body, as a natural tendency is to try to press a lens into the body when trying to rotate it forcefully.

If the twisting and compressive forces are sufficient, then, maybe the camera body will flex a bit.

These pictures show how little mechanical clearance exists between the floating assembly and the shutter frame that is fixed to the body shell:

Very little mechanical clearance between the black "floating" frame and the greenish, fixed shutter frame

Very little mechanical clearance between the black "floating" frame and the greenish, fixed shutter frame. The screw head has a diameter of about 3mm, indicating the screw has backed out about 0.5mm

Since there's so little mechanical clearance between the floating assembly and the shutter frame, it's not impossible that twisting and pressure could be communicated to the floating assembly via the shutter frame if the body flexes enough.

Note that, from a torsional and lateral movement perspectives, the floating frame's freedom of movement will, ultimately, be restricted by the stops built into the strong L-shaped steel brackets holding the permanent magnets. After the floating frame reaches these stops, it might then be subject to the full twisting and pressure constraints communicated to it, say, via the fairly thick optical stack being locked into the fixed shutter opening gate. A twisting / flexing of the shutter opening gate might thus interact, mechanically, directly on the optical stack.

The optical stack protrudes significantly above the screw heads, and we already know that the mechanical clearance between said screw heads and the fixed shutter frame is quite limited. It's thus not impossible, IMHO, that the optical stack might get "locked" into the gate of the fixed shutter frame and get twisted with it.

The fractures of the black plastic floating frame near the holding screws, and the popped off retaining clip observed by LensRentals, are consistent, IMHO, with said frame having been subjected tocompression and / or twisting.

Fracture of the floating frame near mounting screw, and popped-off clop are consistent with significant pressure and twisting constraints being applied to said floating frame.

Personally, I have some doubts about the rigidity of the A7 series' body shell and its ability to resist an energetic, muscular torsion and pressure without any deformation.

Besides, observing the sensor being moved by the IBIS during a long exposure of, say, 10 seconds, the observation of the movement being thankfully made easier by the minute dust particles sitting on the sensor glass which I should probably clean, show that the movements are quite slow. I doubt that such movements would yield enough acceleration to subject the floating frame to such mechanical constraints as would cause fractures of the plastic frame or of magnesium pins, or have enough force to pop a retaining clip.

Kumsa
OP Kumsa Contributing Member • Posts: 623
Re: IBIS Fractures ? Is that a thing ?

As the OP, here's where the discussion has led me:

  • There doesn't appear a lot of personal anecdotes about IBIS fractures/failures.
  • While Cicala has identified fractures as a real-world concern, we are only a few years into mirrorless builds. It's likely that newer models will include improvements to obviate the occurrence of IBIS fractures (that is an assumption). I'm guessing that the next time we get a IBIS camera teardown, there will be some analysis specific to the IBIS frame, etc.
  • I prefer buying used equipment, when possible. I don't purchase equipment that's more than a couple of years in use. For a mirrorless camera, I'll probably want to shorten that duration.

Thanks all !

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