I never understood the use of blade until u showed it by moving beyond the focal point. Recently I was taught schlieren in my engineering class, but this is where I truly learnt it.
Thanks! Yea, I refer to his book now and again. I figure most people probably don't have access to his book (since it's a little pricey), and it's also nice to see what happens in real-time.
Great video, I didnt find this calibration tips anywhere else. Ive 1 question also: for what reason I see the candle flame doubled, in my schlieren set up?
Thanks! You probably have your light source and the reflected beam spot focus too far apart. Try moving the reflected beam spot closer to the light source (as close as you can), and the double image should disappear.
This video is amazing.and really helpful. I am trying to get some results at home with a cellphone and a really cheap mirror and is kind of working. Actually, I got some images of a flame and it flow using genital light and the cellphone camera. They are nothing like the one you showed, but I was amazed that some results can be obtained without both the LED and the knife
ua-cam.com/video/gDhPddrkF_Y/v-deo.html I make this video setting the camera in the focus on the mirror, and was also able to see the effect with my bare eyes
Thanks! Yea, you can sometimes get pretty good results even with cheaper mirrors. I saw the video you posted, and it looked like the mirror is similar to my "bathroom/makeup mirror" that I used at the end of my DIY schlieren video. It's not going to give you great results, but you can definitely see something.
I faced some problem while doing this. 1. I could not find proper focus point. From the method of phone's flash and crispy focus image, I got the point, but when I placed the blade there it is blocking the view and looks like in front of focus. Even when I put the blade on almost the camera lens it still looks like in front of focus. 2. I saw two parallel images of the candle flame on the camera and that is also without the blade, some kind of schlieren effect was there. I don't know what is causing it but I guess it happens due to wrong position of camera. Please help if anyone has faced such problem and solved it.
The focal point actually is a small circle, so it depends how much of it is obstructed by the edge. If you obstruct it entirely there will be no light at all.
You might not be placing the knife edge at the correct location. In my video, you can see that the knife edge will start to totally black out the mirror if it's in front of or behind the focus. When it's located at the correct location, it will start to dim the entire mirror uniformly. Of course, if the razor is placed such that it blocks all the light from the mirror, then you won't see anything on your camera.
I am also trying this experiment. But there is one problem. In your "How To: Build Your Own Schlieren Setup" video, the bright image captured by the camera was not a mirror size. But this time, exactly the same bright image and mirror size. I want to know how to capture a camera exactly same bright circle image as a mirror.
Two things are different between this video and my other video. First is that I was able to use a bigger mirror. Second is that I got a lens with higher zoom. In the first video, the max zoom I had was 55 mm, and with my new lens, I could go up to 200 mm. Both of those points means I was able to get a bigger image of the mirror in my videos. If you don't have a bigger mirror, and you don't have a higher zoom lens, one way you can get a bigger image (although maybe not as nice as going directly into the camera) is to place a sheet of paper farther back behind where you would normally place your camera, and you can see the image on the paper. Then you just point your camera at the piece of paper to get whatever size you want. Normally for something like this, you would use a ground-glass plate.
@@JoshTheEngineer Thank you Josh, but i have a question. I use a 30cm mirror and a 200mm zoom lens. You are creating a schlieren image that is as big as the mirror. But even with camera zoom, I get a schlieren image that is smaller than the mirror size. What am I supposed to change to produce the mirror size schlieren image?
hello, I what to ask you a question. Thanks . Will schlieren work if we are trying to watch the shock wave in the circular pipe. the pipe is glass and 12cm in diameter and 1cm in chickness. actually, I want to now Circular structure will make schileren impossible?
For 40 seconds, 3:00 - 3:40 the moment you blow the fkame, there is NO flame seen actually even tho you said so. So this part is unclear physics. Otherwise it's perfect demonstrating the impressive 'magic'. 2:07- the focal point theorectically is a point in space that occupies no physical space, thus is like the so-called counterintuitive singularity in the big bang theory :)
I never understood the use of blade until u showed it by moving beyond the focal point. Recently I was taught schlieren in my engineering class, but this is where I truly learnt it.
Thank you nice video..I was searching Schlieren imaging arrangements am above 56 still student , thank you teacher...
Thanks a lot for these vids Josh. I made my own Schlieren setup today!
You're welcome! And that's great!
Great video . i alway wonder why we need lazer blade now i get it .thanks alot .
You're welcome!
top video, you must see this if you want to test schlieten effect !
Thanks!
Thanks man! Great, informative video. I have a 12in Parabolic mirror in the mail on the way, and this video was very helpful.
Hi Josh. You should refer the book on schlieren by G S Settles. He covers this extensively. Great vid!
Thanks! Yea, I refer to his book now and again. I figure most people probably don't have access to his book (since it's a little pricey), and it's also nice to see what happens in real-time.
Thanks buddy, for pointing out such a great reference. It was really helpful for me.
Thanks a lot for the precisions you seem to be the only one to give :)
The other video was nice too, but this part was missing in it ;)
Thanks, I appreciate it! Yea, I realized I was missing this information in my original video, so I made this to help supplement that one!
This is really helpful for me ,thanks
Glad I could help!
Gracias.
Great video, I didnt find this calibration tips anywhere else.
Ive 1 question also: for what reason I see the candle flame doubled, in my schlieren set up?
Thanks! You probably have your light source and the reflected beam spot focus too far apart. Try moving the reflected beam spot closer to the light source (as close as you can), and the double image should disappear.
This video is amazing.and really helpful. I am trying to get some results at home with a cellphone and a really cheap mirror and is kind of working. Actually, I got some images of a flame and it flow using genital light and the cellphone camera. They are nothing like the one you showed, but I was amazed that some results can be obtained without both the LED and the knife
ua-cam.com/video/gDhPddrkF_Y/v-deo.html
I make this video setting the camera in the focus on the mirror, and was also able to see the effect with my bare eyes
Thanks! Yea, you can sometimes get pretty good results even with cheaper mirrors. I saw the video you posted, and it looked like the mirror is similar to my "bathroom/makeup mirror" that I used at the end of my DIY schlieren video. It's not going to give you great results, but you can definitely see something.
AWESOME!!
Thanks!
I faced some problem while doing this.
1. I could not find proper focus point. From the method of phone's flash and crispy focus image, I got the point, but when I placed the blade there it is blocking the view and looks like in front of focus. Even when I put the blade on almost the camera lens it still looks like in front of focus.
2. I saw two parallel images of the candle flame on the camera and that is also without the blade, some kind of schlieren effect was there. I don't know what is causing it but I guess it happens due to wrong position of camera.
Please help if anyone has faced such problem and solved it.
Does anyone know the principle behind it? It doesn't make sense to me that the blade does not blackout all the light when it is on the focus point.
The focal point actually is a small circle, so it depends how much of it is obstructed by the edge. If you obstruct it entirely there will be no light at all.
Hi, in my setup I see the knife in my videos ,so I can't see the background if I put the edge in, but in your you can see the background, why?
You might not be placing the knife edge at the correct location. In my video, you can see that the knife edge will start to totally black out the mirror if it's in front of or behind the focus. When it's located at the correct location, it will start to dim the entire mirror uniformly. Of course, if the razor is placed such that it blocks all the light from the mirror, then you won't see anything on your camera.
I am also trying this experiment. But there is one problem. In your "How To: Build Your Own Schlieren Setup" video, the bright image captured by the camera was not a mirror size. But this time, exactly the same bright image and mirror size. I want to know how to capture a camera exactly same bright circle image as a mirror.
Two things are different between this video and my other video. First is that I was able to use a bigger mirror. Second is that I got a lens with higher zoom. In the first video, the max zoom I had was 55 mm, and with my new lens, I could go up to 200 mm. Both of those points means I was able to get a bigger image of the mirror in my videos. If you don't have a bigger mirror, and you don't have a higher zoom lens, one way you can get a bigger image (although maybe not as nice as going directly into the camera) is to place a sheet of paper farther back behind where you would normally place your camera, and you can see the image on the paper. Then you just point your camera at the piece of paper to get whatever size you want. Normally for something like this, you would use a ground-glass plate.
@@JoshTheEngineer Thank you Josh, but i have a question.
I use a 30cm mirror and a 200mm zoom lens. You are creating a schlieren image that is as big as the mirror. But even with camera zoom, I get a schlieren image that is smaller than the mirror size. What am I supposed to change to produce the mirror size schlieren image?
My teacher never explained the reason behind the knife edge.
hello, I what to ask you a question. Thanks . Will schlieren work if we are trying to watch the shock wave in the circular pipe. the pipe is glass and 12cm in diameter and 1cm in chickness. actually, I want to now Circular structure will make schileren impossible?
For 40 seconds, 3:00 - 3:40 the moment you blow the fkame, there is NO flame seen actually even tho you said so. So this part is unclear physics. Otherwise it's perfect demonstrating the impressive 'magic'.
2:07- the focal point theorectically is a point in space that occupies no physical space, thus is like the so-called counterintuitive singularity in the big bang theory :)
Auras are real
u sound like idubbz wtf?
I don't know who that is.
This guy needs a course in public speaking.