The difference between digital camera sensor artifacts and DEW lasers
I would like to share some information that will help people discern
what they are seeing as they analyze imagery while researching or
documenting DEW "events".
Digital sensors create various anomalies. Each artifact depends on the type of sensor (CCD or CMOS). Some will make line-like flares called a “smear” or “horizontal blooming”, there is also “vertical blooming”. Some systems were designed to put black dots in the center when overloaded as a means of protection.
Here is a short example. https://www.youtube.com/watch?v=ICSRTeyOSNU
Pink is the artifact.
Variations in this artifact also depend on aperture and shutter speed. The blooming effect is worse on cameras with electronic shutter than manual shutters.
Sensor artifacts are different from lens flares.
There are other artifacts to deal with digital cameras that make them rather dubious in terms of evidence documentation.
Film cameras did not do this, although they had their own set of issues…
Here are a few examples to consider.
Freeze frame from a video showing sensor artifact. Not laser beams.
Not saying that this wasn't hit by one earlier, but that's a serving of sensor artifact with some lens flare on the side.
These screenshots were taken from this clip. https://www.facebook.com/tyler.collinsblankenship/videos/2019651121449228/?comment_id=2019790054768668&reply_comment_id=2020473348033672&notif_id=1542808811654887&notif_t=video_reply&ref=notif
You should watch it for context.
It's short. I'll wait...
Smear artifact triggered by person taking image with flash on phone
See the person holding up phone before and AFTER the flash induced artifact.
The light overloads the senor when the flash goes off, creating an artifact. Not a laser beam strike.
Notice there is no reaction. If it were a laser strike, you would see and hear the cause/effect relationship. Like that person being incinerated for example...
:)
Here are more examples to drive the point.
For comparison, these are still images demonstrating what one may safely assume is a laser strike.
Notice the visible reactions, the smoke, fire, explosion etc. If it were video clips, you would hear the reactions as well.
One key difference you will notice is that when lasers are used you will see and hear a reaction. Although you may not always see the laser itself. They generally make little/no sound.
Some are visible, others are not. Particulates in the air can allow one to see otherwise invisible beams. There are many factors to consider.
There are MANY different types of lasers, including gas, chemical, excimer and solid state.
The MIRACL chemical lasers use fluoride.
Prozac is made from fluorine/fluoride as well. (Fun note.)
(Neither are used for cleaning teeth)…
There are some DEWs that are designed to mimic lightning bolts, these are laser guided to keep the beam from straying to far from it's target.
This clip really brings it all together...
A few fun clips for consideration.
My Homemade 40W LASER SHOTGUN!!!!!
https://youtu.be/iVrJUbeuG44
https://www.youtube.com/watch?v=iVrJUbeuG44
Laser beam: Lockheed Martin to design high-energy laser weapon system for US jets - TomoNews
https://youtu.be/JJRSyRvdlV8
Here's What A New Laser Weapon Did To A Truck Mile Away
https://youtu.be/xlEc6jM1k58
Watch Lockheed Martin's laser beam system burn drones out of the sky
https://youtu.be/XH6NIazR5pA
US Navy's new drone-killing laser
https://youtu.be/9ElNjgZCDpQ
Watch the US Navy's laser weapon in action
https://youtu.be/tyUh_xSjvXQ
RAW USA Military Tests Laser Weapon Hit Missile @ Speed Of Light Breaking News July 19 2017
https://youtu.be/CsPQcE0xKvo
News MRZR ATV Shoots Down Drones With High Energy Laser Weapon
https://youtu.be/2VPT6tkHTkc
DRONE KILLING LASER cannon live-fire! (U.S. Navy tests FUTURISTIC PHOTON WEAPON! LaWS in ACTION!)
https://youtu.be/NU0VNdzhhA8
Here is a collection of some DEW examples to compare. https://krakahead.blogspot.com/2017/10/theres-something-wild-about-these-new.html
Here is some more information and a few explanations from others on the subject of sensor artifacts.
"Blooming is an effect where the charge developed on a pixel leaks into adjacent pixels and corrupts the scene. It typically occurs when there are very bright spots in the scene, and it diminishes the accuracy of the pixel data as information from one pixel is then present in adjacent pixels.
Smear can be generated directly or indirectly in the vertical shift registers (VCCD) of an interline transfer CCD (IL-CCD). The VCCD is a light-shielded area of the image sensor used to transfer the charge off of the sensor. Smear typically results from very bright spots in an image and is caused by either:"
https://www.adimec.com/ccd-versus-cmos-blooming-and-smear-performance/
"The blooming that you're seeing in your image isn't being caused when the data is shifted out. It's actual electrical charge leaking from one pixel to the next.
CCDs can exhibit shift register blooming as well. Shift register blooming is more along the lines of what you're describing, where the pixel value overflows the shift register and causes a short bloom in a single direction. But CCDs are typically designed such that the maximum pixel value is less than the register capacity, so overflows can only occur in circumstances most users won't ever encounter."
"Blooming is leakage of photo-receptor charge from one cell to the next due to extreme exposure. I'm not sure about this, but I think one of the things that causes it is local heating due to the high intensity light. In the extreme, it can leak across an entire row of receptor cells, even ones that aren't in close proximity to the light. Though I don't know for sure, that's what I would guess caused the horizontal line in the one photo.
You should read about blooming, but it is worse on cameras that use an electronic shutter in addition to the mechanical shutter (which is many, if not all digital cameras these days). That's because at high shutter speeds like 1/2000th, the mechanical shutter stays open longer than thae actual exposure (it stays open usually around 1/250-1/500th) and then the electronic shutter is used to implement the 1/2000th timing. For an image like this, the sensor is getting heated by the hotspot in your image for the entire 1/500th, not just for the 1/2000th. That's why it's important to use a smaller aperture which results in a slower shutter speed. For anything over 1/500th, the sensor is going to get heated by the light for the full 1/500th anyway because that's how long the mechanical shutter is open and is letting light hit the sensor. If you stop down to a smaller f-stop, then less light hits the sensor during the 1/500th that the mechanical shutter is open.
The recommendation I've heard is to pick an aperture that results in a shutter speed no faster than 1/500th and you will typically not get blooming.
A large aperture with a fast shutter speed is the worst condition for blooming as you are letting the most light in during the fixed time that the mechanical shutter is open."
"If too much light impinges on a given pixel in some CMOS image sensors, the potential well of that pixel can spill over and increase the reference level (this is called 'blooming' for CCD sensors). This in turn, causes an error in the sensor's output due to the subtraction of signal and reference. Since the subtraction results in a negative value, the output of the sensor is set to zero. Thus the 'black spots' appear in a field of bright pixels."
Reference https://www.physicsforums.com/threads/black-sun-effect-in-cmos-sensors.799334/
Examples and info
https://www.youtube.com/watch?v=MytCfECfqWc
https://www.youtube.com/watch?v=Dw9wBcVYQzA
https://www.youtube.com/watch?v=-DoTgQbALU0
https://www.youtube.com/watch?v=j8jaiJjgOrQ
https://www.youtube.com/watch?v=dvVerMvUOkc
https://www.youtube.com/watch?v=ICSRTeyOSNU
References.
http://www.gatan.com/ccd-vs-cmos
https://www.adimec.com/ccd-versus-cmos-blooming-and-smear-performance/
https://www.physicsforums.com/threads/black-sun-effect-in-cmos-sensors.799334/
https://www.dpreview.com/forums/thread/1088925
http://www.dslrbodies.com/cameras/camera-articles/sensors/how-sensors-work/
https://www.researchgate.net/post/What_causes_the_black_sun_to_appear_in_CMOS_image
https://www.researchgate.net/figure/The-generation-process-of-the-smear-dot-above-the-light-source-position-The-orange-sun_fig6_315944464
https://www.reddit.com/r/askscience/comments/1w1j81/vertical_smear_on_a_ccd_why_does_it_extend_in/
Digital sensors create various anomalies. Each artifact depends on the type of sensor (CCD or CMOS). Some will make line-like flares called a “smear” or “horizontal blooming”, there is also “vertical blooming”. Some systems were designed to put black dots in the center when overloaded as a means of protection.
Here is a short example. https://www.youtube.com/watch?v=ICSRTeyOSNU
Pink is the artifact.
Variations in this artifact also depend on aperture and shutter speed. The blooming effect is worse on cameras with electronic shutter than manual shutters.
Sensor artifacts are different from lens flares.
There are other artifacts to deal with digital cameras that make them rather dubious in terms of evidence documentation.
Film cameras did not do this, although they had their own set of issues…
Not saying that this wasn't hit by one earlier, but that's a serving of sensor artifact with some lens flare on the side.
These screenshots were taken from this clip. https://www.facebook.com/tyler.collinsblankenship/videos/2019651121449228/?comment_id=2019790054768668&reply_comment_id=2020473348033672&notif_id=1542808811654887&notif_t=video_reply&ref=notif
You should watch it for context.
It's short. I'll wait...
Smear artifact triggered by person taking image with flash on phone
See the person holding up phone before and AFTER the flash induced artifact.
The light overloads the senor when the flash goes off, creating an artifact. Not a laser beam strike.
Notice there is no reaction. If it were a laser strike, you would see and hear the cause/effect relationship. Like that person being incinerated for example...
:)
Here are more examples to drive the point.
For comparison, these are still images demonstrating what one may safely assume is a laser strike.
Notice the visible reactions, the smoke, fire, explosion etc. If it were video clips, you would hear the reactions as well.
One key difference you will notice is that when lasers are used you will see and hear a reaction. Although you may not always see the laser itself. They generally make little/no sound.
Some are visible, others are not. Particulates in the air can allow one to see otherwise invisible beams. There are many factors to consider.
There are MANY different types of lasers, including gas, chemical, excimer and solid state.
The MIRACL chemical lasers use fluoride.
Prozac is made from fluorine/fluoride as well. (Fun note.)
(Neither are used for cleaning teeth)…
There are some DEWs that are designed to mimic lightning bolts, these are laser guided to keep the beam from straying to far from it's target.
This clip really brings it all together...
A few fun clips for consideration.
My Homemade 40W LASER SHOTGUN!!!!!
https://youtu.be/iVrJUbeuG44
https://www.youtube.com/watch?v=iVrJUbeuG44
Laser beam: Lockheed Martin to design high-energy laser weapon system for US jets - TomoNews
https://youtu.be/JJRSyRvdlV8
Here's What A New Laser Weapon Did To A Truck Mile Away
https://youtu.be/xlEc6jM1k58
Watch Lockheed Martin's laser beam system burn drones out of the sky
https://youtu.be/XH6NIazR5pA
US Navy's new drone-killing laser
https://youtu.be/9ElNjgZCDpQ
Watch the US Navy's laser weapon in action
https://youtu.be/tyUh_xSjvXQ
RAW USA Military Tests Laser Weapon Hit Missile @ Speed Of Light Breaking News July 19 2017
https://youtu.be/CsPQcE0xKvo
News MRZR ATV Shoots Down Drones With High Energy Laser Weapon
https://youtu.be/2VPT6tkHTkc
DRONE KILLING LASER cannon live-fire! (U.S. Navy tests FUTURISTIC PHOTON WEAPON! LaWS in ACTION!)
https://youtu.be/NU0VNdzhhA8
Here is a collection of some DEW examples to compare. https://krakahead.blogspot.com/2017/10/theres-something-wild-about-these-new.html
Here is some more information and a few explanations from others on the subject of sensor artifacts.
"Blooming is an effect where the charge developed on a pixel leaks into adjacent pixels and corrupts the scene. It typically occurs when there are very bright spots in the scene, and it diminishes the accuracy of the pixel data as information from one pixel is then present in adjacent pixels.
Smear can be generated directly or indirectly in the vertical shift registers (VCCD) of an interline transfer CCD (IL-CCD). The VCCD is a light-shielded area of the image sensor used to transfer the charge off of the sensor. Smear typically results from very bright spots in an image and is caused by either:"
https://www.adimec.com/ccd-versus-cmos-blooming-and-smear-performance/
"The blooming that you're seeing in your image isn't being caused when the data is shifted out. It's actual electrical charge leaking from one pixel to the next.
CCDs can exhibit shift register blooming as well. Shift register blooming is more along the lines of what you're describing, where the pixel value overflows the shift register and causes a short bloom in a single direction. But CCDs are typically designed such that the maximum pixel value is less than the register capacity, so overflows can only occur in circumstances most users won't ever encounter."
"Blooming is leakage of photo-receptor charge from one cell to the next due to extreme exposure. I'm not sure about this, but I think one of the things that causes it is local heating due to the high intensity light. In the extreme, it can leak across an entire row of receptor cells, even ones that aren't in close proximity to the light. Though I don't know for sure, that's what I would guess caused the horizontal line in the one photo.
You should read about blooming, but it is worse on cameras that use an electronic shutter in addition to the mechanical shutter (which is many, if not all digital cameras these days). That's because at high shutter speeds like 1/2000th, the mechanical shutter stays open longer than thae actual exposure (it stays open usually around 1/250-1/500th) and then the electronic shutter is used to implement the 1/2000th timing. For an image like this, the sensor is getting heated by the hotspot in your image for the entire 1/500th, not just for the 1/2000th. That's why it's important to use a smaller aperture which results in a slower shutter speed. For anything over 1/500th, the sensor is going to get heated by the light for the full 1/500th anyway because that's how long the mechanical shutter is open and is letting light hit the sensor. If you stop down to a smaller f-stop, then less light hits the sensor during the 1/500th that the mechanical shutter is open.
The recommendation I've heard is to pick an aperture that results in a shutter speed no faster than 1/500th and you will typically not get blooming.
A large aperture with a fast shutter speed is the worst condition for blooming as you are letting the most light in during the fixed time that the mechanical shutter is open."
"If too much light impinges on a given pixel in some CMOS image sensors, the potential well of that pixel can spill over and increase the reference level (this is called 'blooming' for CCD sensors). This in turn, causes an error in the sensor's output due to the subtraction of signal and reference. Since the subtraction results in a negative value, the output of the sensor is set to zero. Thus the 'black spots' appear in a field of bright pixels."
Reference https://www.physicsforums.com/threads/black-sun-effect-in-cmos-sensors.799334/
Examples and info
https://www.youtube.com/watch?v=MytCfECfqWc
https://www.youtube.com/watch?v=Dw9wBcVYQzA
https://www.youtube.com/watch?v=-DoTgQbALU0
https://www.youtube.com/watch?v=j8jaiJjgOrQ
https://www.youtube.com/watch?v=dvVerMvUOkc
https://www.youtube.com/watch?v=ICSRTeyOSNU
References.
http://www.gatan.com/ccd-vs-cmos
https://www.adimec.com/ccd-versus-cmos-blooming-and-smear-performance/
https://www.physicsforums.com/threads/black-sun-effect-in-cmos-sensors.799334/
https://www.dpreview.com/forums/thread/1088925
http://www.dslrbodies.com/cameras/camera-articles/sensors/how-sensors-work/
https://www.researchgate.net/post/What_causes_the_black_sun_to_appear_in_CMOS_image
https://www.researchgate.net/figure/The-generation-process-of-the-smear-dot-above-the-light-source-position-The-orange-sun_fig6_315944464
https://www.reddit.com/r/askscience/comments/1w1j81/vertical_smear_on_a_ccd_why_does_it_extend_in/
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