[nobody]

What is it?

[UncleVanya]

Sensors read out one line at a time generally. The electronic shutter speeds stated are not entirely accurate when you look at the total time for reading out the entire sensor. The Q series for example takes about 1/13 seconds no matter how fast the electronic shutter is set. The scanning occurs top to bottom or vice versa typically and the position of the objects can move during the exposure. This can give the illusion of curving lines etc by virtue of the position shifting. A good example is pictures made from a moving car of telephone poles, the will appear to lean.

[nobody]

So, if camera is equipped with mechanical shutter will this phenomenon appears? I guess no, am I right?

[UncleVanya]

So, if camera is equipped with mechanical shutter will this phenomenon appears? I guess no, am I right?

If the mechanical shutter was pure open and closed yes. But none other than leaf shutters are. A traveling slit is used to increase effective shutter speeds. However it is less of an issue. Electronic shutter, rolling shutter and flash: what you need to know: Digital Photography Review

[nobody]

Thanks for explanation UncleVanya. Much appreciated.

[stevebrot]

So, if camera is equipped with mechanical shutter will this phenomenon appears? I guess no, am I right?

If the mechanical shutter was pure open and closed yes. But none other than leaf shutters are. A traveling slit is used to increase effective shutter speeds. However it is less of an issue. Electronic shutter, rolling shutter and flash: what you need to know: Digital Photography Review

Even leaf shutters are vulnerable to time-based image distortion in that the action is not quite global. It depends on the shutter design (blade speed and nature of blade travel) as well as the direction and speed of the motion. The term "rolling shutter" (should probably be called "shutter roll") is fairly new and generally is applied to motion artifact for digital capture, particularly video.

On your (the OP's) K-3 the main concern is for video capture and the rolling shutter effects are easily seen when they happen. For still image capture, the focal plane shutter may still result in some distortion with moving objects and while panning, but is usually subtle enough to not be particularly noticeable. The most common example might be the wheels of moving vehicles or a ball in motion where an oval rather than round face-on appearance is the norm for non-flash photos.


Steve

[nobody]

Thanks guys. Now I know.

[reh321]

Even leaf shutters are vulnerable to time-based image distortion in that the action is not quite global. It depends on the shutter design (blade speed and nature of blade travel) as well as the direction and speed of the motion. The term "rolling shutter" (should probably be called "shutter roll") is fairly new and generally is applied to motion artifact for digital capture, particularly video.

"Q" family lenses have leaf shutters, and the only time "rolling shutter" becomes an issue is when only the "electronic shutter" is used, for example when using a non-Pentax adapter {with no leaf shutter"} or disabling the leaf shutter built into the lens.

[stevebrot]

"Q" family lenses have leaf shutters, and the only time "rolling shutter" becomes an issue is when only the "electronic shutter" is used, for example when using a non-Pentax adapter {with no leaf shutter"} or disabling the leaf shutter built into the lens.

For most subjects that would be true and without knowing how the shutter moves for the Q (some are remarkably simple guillotine affairs), it is difficult to propose a scenario. It is probably enough to say that for the most common types, any element tracking the blade(s) movement across the frame during exposure will be distorted, assuming it is recorded at all.


Steve

[reh321]

For most subjects that would be true and without knowing how the shutter moves for the Q (some are remarkably simple guillotine affairs), it is difficult to propose a scenario. It is probably enough to say that for the most common types, any element tracking the blade(s) movement across the frame during exposure will be distorted, assuming it is recorded at all.

Steve

Rolling Shutter in the "Q" comes from using only the electronic shutter - which reads the sensor row-by-row from top to bottom - without aid of the mechanical leaf shutter. Below is an example I took several years ago for a discussion elsewhere - using my Q-7 + 01 lens with leaf shutter turned off.

[stevebrot]

Rolling Shutter in the "Q" comes from using only the electronic shutter - which reads the sensor row-by-row from top to bottom - without aid of the mechanical leaf shutter. Below is an example I took several years ago for a discussion elsewhere - using my Q-7 + 01 lens with leaf shutter turned off.

Mechanical shutter anomalies are as old as photography and traceable to physical laws, but if the Q has conquered them, what can I say except that the accomplishment (global mechanical shutter) is extraordinary.


Steve

[reh321]

Mechanical shutter anomalies are as old as photography and traceable to physical laws, but if the Q has conquered them, what can I say except that the accomplishment (global mechanical shutter) is extraordinary.


Steve

If you get enough subject speed, mechanical shutters can still give problems. As UncleVanya explained in #2 above, most modern "rolling shutter" issues occur with reading the sensor when not aided by a mechanical shutter. Sony is making progress towards a true "global shutter"; however their latest camera have an "electronic shutter" that reads a group of rows at a time, and that leads to banding problems when taking pictures under LED lighting.

[stevebrot]

If you get enough subject speed, mechanical shutters can still give problems.

Indeed, that is the classic case and nothing has changed. The term "rolling shutter" is fairly recent and refers capture anomaly caused primarily by how digital sensors are managed with regard to so-called electronic shutters, but the principle is the same.

I am not sure, but I believe that many leaf shutters have issues with rotary fan blades as do focal plane shutters. I could test, but my leaf shutter lenses at present are all for the view camera. OTOH, I do have an unfinished roll of 120 in one of my film holders


Steve

[UncleVanya]

I have yet to find any reference to any shutter effects from Leaf Shutters that resemble rolling shutter. This video claims that the opening and closing works like a tiny aperture and the entire frame is always getting exposed the entire time the shutter is open even when just a tiny hole.

You Tube

You Tube