IBIS Fractures ? Is that a thing ?

Started 3 months ago | Discussions thread
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.

Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark MMy threads
Color scheme? Blue / Yellow