[BarryE]

Back in the good old days the front of the lens shutter was often the lens cap. Those old tintype and daguerreotype plates were slow.

... and it portrayed the subjects as morose, unhappy souls which was a little unfair as it wasn't possible to hold a smile for the many seconds it took to capture the image, and now we moan (I do too) about a slight and occasional vibration. In 100 years time, I wonder what our successors will be moaning about? Possibly a suitable subject for a separate Giveaway thread ;-)

[jbinpg]

I would like to see the referred experiments redone using a big beanbag for camera support. I suspect the results would be different.

[pschlute]

When the IBIS system pushes on the sensor in one direction, the counter-reaction forces push the camera body in the opposite direction. The IBIS system then measures that body motion, computes the correction, and creates a counter-counter motion. Under most conditions, this feedback loop stabilizes the oscillation. However, if the natural operating frequency of the SR system happens to be an odd multiple of the natural resonant frequency of the tripod-head-camera-lens system, then the oscillations grow until the sensor is bouncing back and forth and all hell will break loose.

This exactly describes my brain process when I try to stagger home from the pub drunk.

---------- Post added 10-27-19 at 12:45 AM ----------

I would like to see the referred experiments redone using a big beanbag for camera support. I suspect the results would be different.

Well , you are welcome to contribute

What I can tell you is that a K1 + a long footed lens that will cause shutter shock on a tripod, will not if that lens is held in a vice on a solid workbench. Neither will it, if the lens is secured to a granite kitchen worktop with a strong G clamp.

Hand holding a 250mm lens at 1/100 (with IBIS/SR) would be my prefered option to tripod at 1/100 if I could not use LV/ES. I suspect your beanbag would be better than the tripod too.

[Digitalis]

if the natural operating frequency of the SR system happens to be an odd multiple of the natural resonant frequency of the tripod-head-camera-lens system, then the oscillations grow until the sensor is bouncing back and forth and all hell will break loose.

It would be interesting to see if it is possible to deliberately set up the perfect circumstances for this to happen, it could help with mitigating strategies.

[ecostigny]

I've seen the behavior above with my telephoto zoom (the HD 55-300mm WR) on a tripod. When I tried some handheld shots with it, I got better results. Since my zoom lacks a tripod collar, its front end is free to oscillate. I suspect a beanbag might actually work better at minimizing its vibrations. To the workshop!

[biz-engineer]

However, if the natural operating frequency of the SR system happens to be an odd multiple of the natural resonant frequency of the tripod-head-camera-lens system, then the oscillations grow until the sensor is bouncing back and forth and all hell will break loose.

Shutter shock isn't a problem on tripod, because camera body rigidly fixed on tripod head is used when subject isn't moving, and in that case the slow electronic shutter is fine.
The weakness is when the camera is hand held with a shutter speed that should be around 1/50th s. to 1/150th s. too fast for ES but too slow for getting rid of shutter shock. IBIS can be used in those situations.

[photoptimist]

Shutter shock isn't a problem on tripod, because camera body rigidly fixed on tripod head is used when subject isn't moving, and in that case the slow electronic shutter is fine.
The weakness is when the camera is hand held with a shutter speed that should be around 1/50th s. to 1/150th s. too fast for ES but too slow for getting rid of shutter shock. IBIS can be used in those situations.

First, there's no such thing as a "rigid" tripod. All tripods and heads flex, some more than others. When worrying about deflections in the microns, things that seem absolutely solid turn out to act like a bunch of springs that turn into tuning forks.

Interestingly, many find there's less shutter shock with hand-held shots. The photographer's two hands, arms, and head add to the mass of the camera-lens system and the tissues act as dampers for resonant effects.

ES is limited to stationary objects and fairly restrictive lighting conditions. Most modern artificial light sources (LED, CFL, fluorescent, etc.) produce banding. ES is also not really compatible with strobes except at very slow sync speeds.

[biz-engineer]

First, there's no such thing as a "rigid" tripod. All tripods and heads flex, some more than others. When worrying about deflections in the microns, things that seem absolutely solid turn out to act like a bunch of springs that turn into tuning forks.Interestingly, many find there's less shutter shock with hand-held shots. The photographer's two hands, arms, and head add to the mass of the camera-lens system and the tissues act as dampers for resonant effects.ES is limited to stationary objects and fairly restrictive lighting conditions. Most modern artificial light sources (LED, CFL, fluorescent, etc.) produce banding. ES is also not really compatible with strobes except at very slow sync speeds.

In any case, nothing of that is a solution to avoiding the range of shutter speed between 1/20th s. and 1/180th s. except doing it manually in M mode or TAv modes. For me the Sony 47RIV is a scam because no one will get 61Mp worth of resolution when shooting people in moderate lighting without flash. Marketing obviously completely omit to tell about that.

[stevebrot]

It would be interesting to see if it is possible to deliberately set up the perfect circumstances for this to happen, it could help with mitigating strategies.

Testing labs are able to do this as a routine matter, but an approximation might be made with a laser pointer (or similar) mounted to the accessory shoe and aimed to center of frame.


Steve

[y0chang]

Micro-four thirds had a shutter shock problem for a while, its not really format but the shock resonance that happens as camera bodies get lighter and lighter.

The solution Micro-four thirds did was a piezoelectric shutter that stopped not the mirror flap vibration but the actual shutter vibration.

[BigMackCam]

In any case, nothing of that is a solution to avoiding the range of shutter speed between 1/20th s. and 1/180th s. except doing it manually in M mode or TAv modes. For me the Sony 47RIV is a scam because no one will get 61Mp worth of resolution when shooting people in moderate lighting without flash. Marketing obviously completely omit to tell about that.

In reality, you're not going to observe shutter shock across the entire 1/20 - 1/180s range, nor with every lens. When it occurs, it'll be most apparent at one or two shutter speeds, on specific lenses and - if they're zooms - probably at specific focal length settings or ranges where the distribution of mass is "just so". Getting to know the combinations where it happens, and at what shutter speeds, with a specific camera and lens combo allows us to work around this quirk. Sometimes, changing your grip will work. Other times, adding or removing mass (battery grip, tripod plate, etc.) will be enough to circumvent the issue, or move where it occurs.

This reminds me somewhat of "dead spots" with guitars. You can take a beautifully crafted, $5,000 hand-made instrument, play it, and find that there's a dead spot - one note on a specific string and fret - where there's little resonance and sustain. It's a lot more common than you'd think, actually. There are a couple of options for the owner... play around it so that you use that note infrequently on its own, or try adding mass to the neck or body (you can buy clip-on or clamp-on devices for this very purpose - or sometimes, a spring capo is sufficient). Of course, that changes the resonance of the entire instrument, so it's not always an ideal solution. But, hey, nothing's perfect, right?

The Sony A7R MkIV is no more a scam than any other piece of equipment. All cameras have limitations. All cameras with moving shutters have the potential for this limitation in certain circumstances. As photographers, we work around the limitation as we would any other. Is it frustrating? Sure. Is it the end of the world? No...

[stevebrot]

The Sony A7R MkIV is no more a scam than any other piece of equipment.

...and certainly no more of a scam than the linked blog entries in the original post. Quite simply the blogger set up to fail and to fail easily in an uncontrolled way. The multitude of graphs are impressive as is a close-to-daily entry rate; both tell me they have a lot of time on their hands or never sleeps or is cutting corners. On the first linked entry there is a photo of the setup. Note that a door is being used for the slant chart and that it is cocked open. Even if closed, I hope no opens the outside door down the hall during an exposure. I would also note that he was using an adapted (F to E) Zeiss ZF 135/2.0 APO Sonnar with the tripod attached at the body. Yes, that is nearly a kilogram of mass (970 gm) attached through a Kipon adapter cantilevered onto a lightweight head attached to a travel tripod. This is clearly not representative of a real-world shooting situation. The amount of injected uncertainty is unreal, but note the lack of air bars on the graphs.

In short, I can't imagine anyone framing a buying decision based on this person's blog entries.


Steve

[stevebrot]

Quite simply the blogger set up to fail and to fail easily in an uncontrolled way.

I forgot to add that a cardinal rule of MTF testing is to never compare between different sensor resolutions.


Steve

[bdery]

Why no one invented a screw on leaf shutter?

Because that's not how the camera controls the aperture. You'd have to bypass the camera's exposure system.

Would it be possible to use the lens iris itself as shutter (by controlled by firmware)

It does not close fully.

Leaf shutters are nice, and offer interesting possibilities, but they are not necessarily without shock effect themselves.

[photoptimist]

Because that's not how the camera controls the aperture. You'd have to bypass the camera's exposure system.



It does not close fully.

Leaf shutters are nice, and offer interesting possibilities, but they are not necessarily without shock effect themselves.

It's also worth noting that leaf shutters are bulky, slow, and expensive. See Copal #3 Shutter (3-567) CO # 3-567 B&H Photo Video

Among currently manufactured leaf shutters for large format cameras, the one with the largest shutter opening (only 45mm so it's too small even for tiny 49mm filter ring lenses) is a beast that weighs over 3/4 pounds, costs $1200, and only goes to 1/125 second.