Best explanation to my question so far. The crucial part here is clear, the sensor exposed to light whole at once and cut off very fast by mechanical shutter, the much slower readout speed can read the "frozen" state of signal on the sensor after. Many explanations found so far missed the important points explained in this video is that the signal is held on sensor for processor to read but readout speed is slow.
Thank you for the explanation David. But I still don't understand one thing: when in mechanical shutter mode the sensor acquires data as a global shutter? If it is not this way, the problem of the readout time should remain, as the curtains move fast, but the sensor cannot achieve such speed and thus we would have an photo with a black band (like the one when you shoot with a flash not in High Sync Speed mode). To explain better: if we imagine the two curtains moving almost parallel (with a fast shutter speed), if the sensor is still exposing one line per one line, if they move faster than the readout speed we would obtain a black part of the image. Otherwise, if the curtains move fast but the sensor behaves like a global shutter sensor, than the image is acquired completely. Thank you if you clarify this topic :)
The light hits the sensor all at once. Light is light. But then the data is "read" and cleared off the sensor and sent to the processor one line at a time.
Stefano, it is not the same. When mechanical shutter is used, the photosites are exposed for long duration of time, what makes "shutterspeed" short is the narrow gap of fast moving curtains across the surface of the sensor. The most of the time the photosites are read, they see just blackness - the curtain in front of them. However, when curtains are not there, you need to have different approach to set very short exposure times. For example, if you set "shutterspeed" to 1/8000, in mechanical mode this duration of exposing each photosite is achieved by curtains' gap, but in electronic mode it is achieved by cutting readout from each photosite electronically. The readout is started and immediatelly after 1/8000 cut off. So yeah, the data flow from each photosite vastly differs wheather camera is in mechanical or electronic mode.
@@PiDsPagePrototypes finally someone clear, thank you: "the light is read off one line at a time AFTER the mechanical shutter is closed". This was the passage I did not understand! So first the light "impress" the sensor, the information is held, and after the shutter is closed the information is read one line per one line, so the readout time is not a problem! THANK PiDsMedia!
@@plemas Think of the pixels on the sensor as buckets that accumulate fotons (particles of light) untill the exposure is over, and they keep them untill the pixel is 'read,' (secuentially on a CMOS sensor), moment in which they release the accumulated fotons in the form of an electric current (measured as voltage). The amount of voltage (from 0 to 1) represents how much photons hit the pixel (from 0 to 100% of capacity) during exposure. In this sense you can say that the sensor has a sort of 'memory' implemented on each pixel.
I like and use ES about 70% of the time for general photography on my Fuji cameras. Switch to mechanical when I am doing flash photography or sports/wildlife and that works well for my needs.
Still shooting mechanical shutter DSLRs here. Thanks for the explanation, and here's a "yes please" vote for an explanation of electronic first-curtain shutters.
Well put David. I currently use 2 Nikon D700 bodies with a variety of Nikkor lenses. I have not made the jump to mirrorless yet due to lack of money and I am not a fan of electronic viewfinders. I am aware of the fact that all digital still cameras use technology from video cameras and have for some time now. I am happy with the image quality of the D700 and in time when money allows get something newer. Thanks and have a good new week! 😎👍🇨🇦
follow-up questions after watching (assuming sensors readout speed is 1/180 of a second) 1. How does readout speed vs electronic shutter speed compare? 2. Is readout speed the same as time to capture the image on the sensor or does readout speed mean something different like time to pass the whole image off to the buffer? 3. How does a DSLR capture the whole image if the shutter closes (says 1/4000 of a second) before the image has been captured on the sensor? Wouldn't the bottom of the image just be black? 4. On a mirrorless camera, if the readout speed is approx 1/180 of a second, does that mean shooting at anything above 1/180 of a second is useless (we are only getting 1/180 even if we shoot at 1/2000)?
1) When using electronic shutter, the duration of time from reading first photosites' row, up to the last row is "sensor readout time", that equals very approx. 1/15s for older or 1/200 for newer sensors. The duration of time for each single photosite is read is the "shutterspeed", or exposure time and is not linked to sensor readout time in any way. 2) I hope that this is answered in 1) 3) The exposure time for each single photosite, with mechanical shutter, is not equal to the set shutterspeed, but it has to be larger than the duration of the whole pass of the curtains' gap over the sensor (~1/200 = that actually equals flash sync speed), or longer (equal to shutterspeed or more if it is lower than that value). 4) No, because photosites' read are cut after exposure time elapses; that doesn't mean that sensor finished reading all lines. I hope this makes sense?
I only use electronic shutter if I need it to be completely silent (like at a golf match - though this is probably when you want to avoid rolling shutter. Unfortunate, that.)
Very interesting video. I've just purchased a Canon M50 Mkii to use for vlogging and will be purchasing an R7 nearer to Christmas good to get an understanding of this rolling shutter. Question: How does a mirrorless camera acquire focus compared to a traditional DSLR. I've noticed with my older 7D how the focus feels different to even the much smaller M50 mkii i have. Also why is micro adjustment redundant when using a mirrorless system?
It seems that the problem with the electronic shutter occurs when the read out speed of the sensor is not fast enough to properly separate the 'exposure' event from the 'read out' event. The mechanical shutter consist of a physical curtain that exposes the entire sensor at practically the same moment in time, so those pixels that haven't been read are prevented from being stimulated by light during the subsequent reading process,. The key is that the mechanical shutter allows a separation between the moment of exposure and the moment of reading. In electronic shutter mode those two events are conflated together generating rolling shutter or banding artifacts in some circumstances. But it is important to mention that in both modes, the pixels are exposed the same amount of total time indicated by the shutter speed (e.g. 1/1000 sec). The key difference then is that in mechanical shutter mode the exposure occurs at roughly the same moment in time for the entire sensor (thanks to the fast physical curtain), and in electronic shutter mode it occurs at significantly distinct moments in time (if the sensor read out speed is slow, for example 1/10 sec or 100 milliseconds), generating rolling shutter and banding effects in some circumstances.
How does the shutter speed work with electronic shutter, if you shoot at 1/4000 and say 1/500 how does an electronic shutter differentiate the two , with mechanical the second curtain will start to close sooner with faster shutter speeds but how does this work with an electronic shutter.
The duration of time the single pixel is read, and the duration of time the scan over the whole area is done are two independent values. The data flow from each photosite is cut off after exposure time finish. It can be extremely short time. The scan time over all photosites cannot be that short to avoid capturing different part of the image at significantly different point in time (yet).
I shoot dance, events and weddings so use my A9 mostly on silent shutter. But I have to use the A74 on mechanical a lot of the time even when there is background noise to drown out the shutter click as under many artificial lights I get banding and light flicker
Can you address optimum light position in outdoor portraiture with the sun or sunset backlighting the subject. I have seen lots of images were the subject is sandwiched between the sun and front lit and it looks so fake. How do you position the light so it appears the sun is wrapping around the subject.
Canon R5, most of the time, electronic first curtain. Why? I can't remember why I landed on it, but have been happy with it. I usually shoot wildlife, some sports (triathlons). Sometimes go full electronic for fast birds in flight, but definitely notice the rolling shutting in those since they are panning shots.
Great explanation!!! I am sure you have experienced this, but I photographed a small concert in TN where they used LED spotlights. When the dimed to spot a little, I had banding on my images when using the electronic shutter on my Canon EOSR. After some research on the lights, I found out that the LED lights are actually pulsed and to make them appear dim, the pulse width of the "on" time to the LED is shortened -- this caused banding (I think) on my images. Not sure if this is all correct, but it was nice to shoot with a silent shutter! Is there any way to get around this while useing the electronic shutter?
mecanical shutter is about 1/200 1/250s, so similar to Z9 or A1 only leaf shuttter is really faster than a Z9 or a A1 electronic shutter (it works differently acting more or less as a diaphragm)
David...It sounds like you are confusing electronic exposure time with readout time. For example, for a 1/10,000 sec exposure, let's have the pixels start receiving photons at time 0 and turn off the pixels at time 0.0001 sec. Then at your leisure you can readout the pixel voltages line by line. It doesn't matter if the readout time is 0.01 sec or an hour. The picture will not have distortion.
good point, but it seems that on a CMOS sensor you can't make all pixels simultaneously start receiving photons at, say, time 0 and being turned all off at time 0.0001 sec. They seem to be turned off when they are 'read' which on a CMOS sensor happens sequentially not simultaneously. The advantage of a mechanical shutter in scenarios with fast moving objects (or fast camera movements) is that a physical mechanical curtain with short exposure time guaranties that those pixels that haven't been read yet stop receiving incoming light, hence minimizing eventual rolling shutter artifacts.
so basically when using mechanical shutter the sensor works as a global shutter receiving light in all their pixels at once as the curtain passes, then it starts reading the collected data at the readout speed. Right??? If not, I dont understand how a fast shutter like 1/4000 would be able to expose a line at the bottom of the sensor that didnt even started collecting data.
I don't understand how the mechanical shutter closing reduces rolling shutter. The read out speed of the censor is still the same and that's what's causing the rolling shutter effect?
Love your videos David! I always learn a ton. I’d love to experience this rolling shutter problem first hand, but I’m still waiting for Canon to deliver more R7’s to their retailers!!! If you are ever working in Phoenix and need an intern/assistant, I’d love the opportunity to learn from one of the best. Take care!
Automatic Rolling Shutters are available in Bangladesh. Also available in various sizes designs and colors, these shutters are highly treasured by our clients due to their features like high tensile strength, fine finish, fire resistance, robust construction, lightweight, and sturdiness. Premium quality raw materials and cutting-edge technology are used in the design of these automatic rolling shutters that ensure their durability. By using the latest technology, these doors are precisely tested by our experts on various quality parameters. Our engineers are ready to serve your desired product options anywhere in Bangladesh. We offer these Automatic Rolling Shutters at a very reasonable price to the clients.
I had to deep into google on this topic in the past as there is not many clear explanation on the internet. I was curious why people said there is no rolling shutter effect on mechanical shutters as mechanical shutters also exposed the film/sensor "line by line". It was until I saw somebody wrote the mechanical shutter moves so fast that the rolling shutter effect becomes insignificant.
The problem started with CMOS sensors. CCDs (charge-coupled devices) are alternatives to CMOS sensors, which are generally more sensitive and more expensive. CCD-based cameras often use global shutters, which take a snapshot representing a “relative” single instant in time and therefore do not suffer from the motion artifacts caused by rolling shutters, but CCD have problems like using too much power and expensive. Now, how do you avoid the rolling shutter effect? to avoid rolling shutter when recording fast motion or panning your camera, adjust your shutter speed to twice your frame rate. Standard cameras shoot at 30 frames per second (fps), so the slowest shutter speed you should use is about 1/60 of a second.
Best explanation to my question so far. The crucial part here is clear, the sensor exposed to light whole at once and cut off very fast by mechanical shutter, the much slower readout speed can read the "frozen" state of signal on the sensor after. Many explanations found so far missed the important points explained in this video is that the signal is held on sensor for processor to read but readout speed is slow.
Very, very interesting. I’m definitely interested in learning more about using the electronic first curtain (hint, hint). Time to experiment!
Send it to www.AskDavidBergman.com :)
Thank you for the explanation David. But I still don't understand one thing: when in mechanical shutter mode the sensor acquires data as a global shutter? If it is not this way, the problem of the readout time should remain, as the curtains move fast, but the sensor cannot achieve such speed and thus we would have an photo with a black band (like the one when you shoot with a flash not in High Sync Speed mode). To explain better: if we imagine the two curtains moving almost parallel (with a fast shutter speed), if the sensor is still exposing one line per one line, if they move faster than the readout speed we would obtain a black part of the image. Otherwise, if the curtains move fast but the sensor behaves like a global shutter sensor, than the image is acquired completely. Thank you if you clarify this topic :)
The light hits the sensor all at once. Light is light. But then the data is "read" and cleared off the sensor and sent to the processor one line at a time.
Stefano, it is not the same. When mechanical shutter is used, the photosites are exposed for long duration of time, what makes "shutterspeed" short is the narrow gap of fast moving curtains across the surface of the sensor. The most of the time the photosites are read, they see just blackness - the curtain in front of them. However, when curtains are not there, you need to have different approach to set very short exposure times. For example, if you set "shutterspeed" to 1/8000, in mechanical mode this duration of exposing each photosite is achieved by curtains' gap, but in electronic mode it is achieved by cutting readout from each photosite electronically. The readout is started and immediatelly after 1/8000 cut off. So yeah, the data flow from each photosite vastly differs wheather camera is in mechanical or electronic mode.
@@PiDsPagePrototypes finally someone clear, thank you: "the light is read off one line at a time AFTER the mechanical shutter is closed". This was the passage I did not understand! So first the light "impress" the sensor, the information is held, and after the shutter is closed the information is read one line per one line, so the readout time is not a problem! THANK PiDsMedia!
Does that mean the sensor has a memory. Otherwise how does the sensor read the light after the mechanical shutter has passed over the sensor???
@@plemas Think of the pixels on the sensor as buckets that accumulate fotons (particles of light) untill the exposure is over, and they keep them untill the pixel is 'read,' (secuentially on a CMOS sensor), moment in which they release the accumulated fotons in the form of an electric current (measured as voltage). The amount of voltage (from 0 to 1) represents how much photons hit the pixel (from 0 to 100% of capacity) during exposure. In this sense you can say that the sensor has a sort of 'memory' implemented on each pixel.
I like and use ES about 70% of the time for general photography on my Fuji cameras. Switch to mechanical when I am doing flash photography or sports/wildlife and that works well for my needs.
Still shooting mechanical shutter DSLRs here. Thanks for the explanation, and here's a "yes please" vote for an explanation of electronic first-curtain shutters.
Well put David. I currently use 2 Nikon D700 bodies with a variety of Nikkor lenses. I have not made the jump to mirrorless yet due to lack of money and I am not a fan of electronic viewfinders. I am aware of the fact that all digital still cameras use technology from video cameras and have for some time now. I am happy with the image quality of the D700 and in time when money allows get something newer. Thanks and have a good new week! 😎👍🇨🇦
follow-up questions after watching (assuming sensors readout speed is 1/180 of a second)
1. How does readout speed vs electronic shutter speed compare?
2. Is readout speed the same as time to capture the image on the sensor or does readout speed mean something different like time to pass the whole image off to the buffer?
3. How does a DSLR capture the whole image if the shutter closes (says 1/4000 of a second) before the image has been captured on the sensor? Wouldn't the bottom of the image just be black?
4. On a mirrorless camera, if the readout speed is approx 1/180 of a second, does that mean shooting at anything above 1/180 of a second is useless (we are only getting 1/180 even if we shoot at 1/2000)?
1) When using electronic shutter, the duration of time from reading first photosites' row, up to the last row is "sensor readout time", that equals very approx. 1/15s for older or 1/200 for newer sensors. The duration of time for each single photosite is read is the "shutterspeed", or exposure time and is not linked to sensor readout time in any way.
2) I hope that this is answered in 1)
3) The exposure time for each single photosite, with mechanical shutter, is not equal to the set shutterspeed, but it has to be larger than the duration of the whole pass of the curtains' gap over the sensor (~1/200 = that actually equals flash sync speed), or longer (equal to shutterspeed or more if it is lower than that value).
4) No, because photosites' read are cut after exposure time elapses; that doesn't mean that sensor finished reading all lines.
I hope this makes sense?
A clear and informed explanation, as always. Thanks.
I only use electronic shutter if I need it to be completely silent (like at a golf match - though this is probably when you want to avoid rolling shutter. Unfortunate, that.)
Has dslr mechanical shutter any pros over mirrorless mechanical shutter?
Very interesting video. I've just purchased a Canon M50 Mkii to use for vlogging and will be purchasing an R7 nearer to Christmas good to get an understanding of this rolling shutter.
Question: How does a mirrorless camera acquire focus compared to a traditional DSLR. I've noticed with my older 7D how the focus feels different to even the much smaller M50 mkii i have. Also why is micro adjustment redundant when using a mirrorless system?
Send your question in at www.AskDavidBergman.com
It seems that the problem with the electronic shutter occurs when the read out speed of the sensor is not fast enough to properly separate the 'exposure' event from the 'read out' event. The mechanical shutter consist of a physical curtain that exposes the entire sensor at practically the same moment in time, so those pixels that haven't been read are prevented from being stimulated by light during the subsequent reading process,. The key is that the mechanical shutter allows a separation between the moment of exposure and the moment of reading. In electronic shutter mode those two events are conflated together generating rolling shutter or banding artifacts in some circumstances. But it is important to mention that in both modes, the pixels are exposed the same amount of total time indicated by the shutter speed (e.g. 1/1000 sec). The key difference then is that in mechanical shutter mode the exposure occurs at roughly the same moment in time for the entire sensor (thanks to the fast physical curtain), and in electronic shutter mode it occurs at significantly distinct moments in time (if the sensor read out speed is slow, for example 1/10 sec or 100 milliseconds), generating rolling shutter and banding effects in some circumstances.
How does the shutter speed work with electronic shutter, if you shoot at 1/4000 and say 1/500 how does an electronic shutter differentiate the two , with mechanical the second curtain will start to close sooner with faster shutter speeds but how does this work with an electronic shutter.
Send the Q to www.AskDavidBergman.com
The duration of time the single pixel is read, and the duration of time the scan over the whole area is done are two independent values. The data flow from each photosite is cut off after exposure time finish. It can be extremely short time. The scan time over all photosites cannot be that short to avoid capturing different part of the image at significantly different point in time (yet).
I shoot dance, events and weddings so use my A9 mostly on silent shutter. But I have to use the A74 on mechanical a lot of the time even when there is background noise to drown out the shutter click as under many artificial lights I get banding and light flicker
Can you address optimum light position in outdoor portraiture with the sun or sunset backlighting the subject. I have seen lots of images were the subject is sandwiched between the sun and front lit and it looks so fake. How do you position the light so it appears the sun is wrapping around the subject.
Send it into www.AskDavidBergman.com
Canon R5, most of the time, electronic first curtain. Why? I can't remember why I landed on it, but have been happy with it. I usually shoot wildlife, some sports (triathlons). Sometimes go full electronic for fast birds in flight, but definitely notice the rolling shutting in those since they are panning shots.
Great explanation!!! I am sure you have experienced this, but I photographed a small concert in TN where they used LED spotlights. When the dimed to spot a little, I had banding on my images when using the electronic shutter on my Canon EOSR. After some research on the lights, I found out that the LED lights are actually pulsed and to make them appear dim, the pulse width of the "on" time to the LED is shortened -- this caused banding (I think) on my images. Not sure if this is all correct, but it was nice to shoot with a silent shutter! Is there any way to get around this while useing the electronic shutter?
Trank you, explained very good
mecanical shutter is about 1/200 1/250s, so similar to Z9 or A1
only leaf shuttter is really faster than a Z9 or a A1 electronic shutter (it works differently acting more or less as a diaphragm)
great info. I shoot mecanical shutter on my Canon R5
Well explained 👍
If an object moves fast enough, a mechanical shutter will also exhibit rolling shutter.
useful content.
David...It sounds like you are confusing electronic exposure time with readout time. For example, for a 1/10,000 sec exposure, let's have the pixels start receiving photons at time 0 and turn off the pixels at time 0.0001 sec. Then at your leisure you can readout the pixel voltages line by line. It doesn't matter if the readout time is 0.01 sec or an hour. The picture will not have distortion.
good point, but it seems that on a CMOS sensor you can't make all pixels simultaneously start receiving photons at, say, time 0 and being turned all off at time 0.0001 sec. They seem to be turned off when they are 'read' which on a CMOS sensor happens sequentially not simultaneously. The advantage of a mechanical shutter in scenarios with fast moving objects (or fast camera movements) is that a physical mechanical curtain with short exposure time guaranties that those pixels that haven't been read yet stop receiving incoming light, hence minimizing eventual rolling shutter artifacts.
So if I keep my camera on a tripod and not pan I shouldn’t have rolling shutter problems while filming basketball game?
You can use electronic shutter on some dslrs as well. When shooting through liveview.
Its not only a use on mirrorless cameras as mentioned.
so basically when using mechanical shutter the sensor works as a global shutter receiving light in all their pixels at once as the curtain passes, then it starts reading the collected data at the readout speed. Right??? If not, I dont understand how a fast shutter like 1/4000 would be able to expose a line at the bottom of the sensor that didnt even started collecting data.
I don't understand how the mechanical shutter closing reduces rolling shutter. The read out speed of the censor is still the same and that's what's causing the rolling shutter effect?
I love these videos!!!!
Love your videos David! I always learn a ton. I’d love to experience this rolling shutter problem first hand, but I’m still waiting for Canon to deliver more R7’s to their retailers!!! If you are ever working in Phoenix and need an intern/assistant, I’d love the opportunity to learn from one of the best. Take care!
Nice 😎
Automatic Rolling Shutters are available in Bangladesh. Also available in various sizes designs and colors, these shutters are highly treasured by our clients due to their features like high tensile strength, fine finish, fire resistance, robust construction, lightweight, and sturdiness. Premium quality raw materials and cutting-edge technology are used in the design of these automatic rolling shutters that ensure their durability. By using the latest technology, these doors are precisely tested by our experts on various quality parameters. Our engineers are ready to serve your desired product options anywhere in Bangladesh. We offer these Automatic Rolling Shutters at a very reasonable price to the clients.
I had to deep into google on this topic in the past as there is not many clear explanation on the internet. I was curious why people said there is no rolling shutter effect on mechanical shutters as mechanical shutters also exposed the film/sensor "line by line". It was until I saw somebody wrote the mechanical shutter moves so fast that the rolling shutter effect becomes insignificant.
The problem started with CMOS sensors. CCDs (charge-coupled devices) are alternatives to CMOS sensors, which are generally more sensitive and more expensive. CCD-based cameras often use global shutters, which take a snapshot representing a “relative” single instant in time and therefore do not suffer from the motion artifacts caused by rolling shutters, but CCD have problems like using too much power and expensive. Now, how do you avoid the rolling shutter effect? to avoid rolling shutter when recording fast motion or panning your camera, adjust your shutter speed to twice your frame rate. Standard cameras shoot at 30 frames per second (fps), so the slowest shutter speed you should use is about 1/60 of a second.
Very disappointing. Poorly done. This topic requires demonstration, pictures, diagrams or animation, not just sitting there talking about it.
He explained the concept quite clearly, but I agree that some illustration would be helpful.
Is this about photo or video?