Diffraction Help: Is This Diffraction?

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The discussion revolves around identifying whether certain visual phenomena captured on video are due to diffraction. Participants suggest that the images appear to be blurry and out of focus rather than true diffraction patterns. The original poster describes observing light reflections from a bio liquid under a street lamp, noting the presence of intriguing structures that resemble diffraction patterns. Experts clarify that while diffraction contributes to image formation, the observed effects are likely due to poor focus and scattering rather than distinct diffraction. The conversation emphasizes the need for clearer descriptions and better-quality images to accurately assess the phenomenon.
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Is this diffraction??Help..sorry if I've posted in the wrong place.
 

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You'll increase your chances of getting a meaningful answer if you describe what these images are.
 
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ZHIHZ said:
Is this diffraction??Help..sorry if I've posted in the wrong place.

just looks like some very blurry -- out of focus, so probably not
 
davenn said:
just looks like some very blurry -- out of focus, so probably not
I have not taken the best pic from the video but please take a look at this short video and tell me what you think.
 
ZHIHZ said:
I have not taken the best pic from the video but please take a look at this short video and tell me what you think.


I still go with my earlier comments ... unfortunately, it's just a meaningless out of focus blur

Dave
 
davenn said:
I still go with my earlier comments ... unfortunately, it's just a meaningless out of focus blur

Dave
Ok.thank you for taking a look anyways.i will keep trying to capture what i can see with my eyes.looks like something to me but the only thing i can find online that looks anything like it are diffraction patterns.
 
ZHIHZ said:
Ok.thank you for taking a look anyways.i will keep trying to capture what i can see with my eyes.looks like something to me but the only thing i can find online that looks anything like it are diffraction patterns.
If you tell us what it is that you are looking at, it would help. When do you reckon you are 'seeing' a diffraction pattern?
I could point out that you cannot get a diffraction pattern with an individual photon and that you need an awful lot of photons to build up a diffraction. But all may be solved if you describe what you have been doing.
 
sophiecentaur said:
If you tell us what it is that you are looking at, it would help. When do you reckon you are 'seeing' a diffraction pattern?
I could point out that you cannot get a diffraction pattern with an individual photon and that you need an awful lot of photons to build up a diffraction. But all may be solved if you describe what you have been doing.
I will try to exsplane best i can later when I've put the kids in bed.i know you can't get diffraction from a notmal light source that's why I am asking you guys to help me figure out what it is.the light source is a normal street lamp and the video is of the light bouncing off a bio liquid.imagine the tiny shimmer you get from a diamond that tiny point of light reflecting.thats what I am trying to focus on.that tiny dot of reflected light at a certain Angeles allows me to see structurs that are like looking at the surface of an alien planet.ive looked all over the web to exsplane it but found nothing..i will upload the full video later to see if that help anyone tell me what it is.thanks
 
ZHIHZ said:
i know you can't get diffraction from a notmal light source that's why I am asking you guys to help me figure out what it is.the light source is a normal streed lamp
What kind of streetlamp? What color is it?
 
  • #10
berkeman said:
What kind of streetlamp? What color is it?
Its a white light..
 

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  • #11


Dont know if this video will help.its a little longer and shows different structures.
 
  • #12

Please watch this video.i have tryed to capture the reflected light from materials.this is reflected light from a water based liqid.the light is reflected from the surface and captured directly into the phones camera.The light is somehow creating structures that seem to eco like a reapeating pattern but each time getting dimmer.Please pause the video at 1.50-1.55 and see for yourself what i mean..close to the end there is a very interesting triangular shape that i can't exsplane.
 
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  • #13
No, the blurring you see is not diffraction. There's always some diffraction that contributes to the blur, but in this case, most of the blur seems to come from poor focus.
 
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  • #14
Khashishi said:
No, the blurring you see is not diffraction. There's always some diffraction that contributes to the blur, but in this case, most of the blur seems to come from poor focus.
If the diffraction was from poor focus of the camera then i would not be able to see it with my eyes would i?
 
  • #15
To be pedantic about this question, I could say that, as diffraction accounts for the formation of any image when you treat the light as waves, everything you see is 'diffraction'. The occasions when there is an identifiable fringe structure will be when there is a limited aperture or where there are multiple path lengths for the waves to get to a destination. The above images and videos are probably due to diffraction due to some small scattering structure in the light path. A great example of this is the diffraction pattern caused by the supports in a Newtonian telescope. You will notice that those spikes are not noticeably 'coloured'. The images in this link seem to be copyright protected so i couldn't post an image but they show what I mean, very well. They do not occur all over the picture - often just where the object is a lot brighter than the surroundings. They can occur without the original object actually turning up in the picture and that's what I think is happening in the above images. There must be a bright source well off axis.
Other examples are what you see when bright lights pass through a wet windscreen when the wipers have gone over a slightly greasy patch and the effect that 'effects filters' (star burst) on cameras will show. There is sometimes a bit of chromatic spread but nothing like as strong as the basic 'white' pattern.
P.S. The main peak in these particular patterns is in the same direction for all wavelengths and the width is small - hence the white appearance.
 
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  • #16
sophiecentaur said:
To be pedantic about this question, I could say that, as diffraction accounts for the formation of any image when you treat the light as waves, everything you see is 'diffraction'. The occasions when there is an identifiable fringe structure will be when there is a limited aperture or where there are multiple path lengths for the waves to get to a destination. The above images and videos are probably due to diffraction due to some small scattering structure in the light path. A great example of this is the diffraction pattern caused by the supports in a Newtonian telescope. You will notice that those spikes are not noticeably 'coloured'. The images in this link seem to be copyright protected so i couldn't post an image but they show what I mean, very well. They do not occur all over the picture - often just where the object is a lot brighter than the surroundings. They can occur without the original object actually turning up in the picture and that's what I think is happening in the above images. There must be a bright source well off axis.
Other examples are what you see when bright lights pass through a wet windscreen when the wipers have gone over a slightly greasy patch and the effect that 'effects filters' (star burst) on cameras will show. There is sometimes a bit of chromatic spread but nothing like as strong as the basic 'white' pattern.
P.S. The main peak in these particular patterns is in the same direction for all wavelengths and the width is small - hence the white appearance.
You are awesome.Thank you so much.i found this picture that is exactly the same as the rectangular patterns i am seeing.https://i.imgur.com/2NyUPtt.jpg
 
  • #17
ZHIHZ said:
the rectangular patterns i am seeing.https://i.imgur.com/2NyUPtt.jpg
Nice image. Of course, it is in monochrome but I suggest that you would actually a slightly 'coloured' outline in the original.
 
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