Hello Could you explain what output parameters mean, such as Angle, Length, Theta C, Uncertainty, Theta Left, Theta Right, Theta E, Radius, Circle StDev, Ellipse StDev, e, Points and Volume what they mean. Thanks
I just downloaded this program today (the day after you published the tutorial!) and was trying to figure out how it worked. Thanks for the straight forward, easy to follow video.
I am glad that was helpful for you. Make sure that the orientation of your photos is correct, the software assumes your droplets are upside down and will give you a reading that is off by 180° if they are oriented like mine.
Hi thanks a lot for your videos it was helpful, but actually i am confused with the results. the true value of theta should be 180° minus the value shown in the results window right? thanks a lot in advance, hope you wound see it. best regards
Thanks for the video. This is my first time of using image J for contact angle measurement. Please which of the thetas' are the advancing and receding contact angle? Thank you. I look forward to hearing your feedback as regards my question.
Thank you for your comment. The ImageJ plugin is only used for static drop analysis and cannot do advancing or receding angles. ThetaC provides the circle based contact angle which works well for ideal drops. The other theta's provided are based on elliptic fits and can account for asymmetric drop formation, but are further removed from the simple Zisman analysis. I hope this helps.
Hey yoyoerx, Could you also explain other terms too? I mean "angle", theta left", "theta right". Any tutorial that may suggest for this particular plugin. Thanks
From what I could gather is that the theta left and right refers to the angle from both sides of the droplet as is the case with other similar contact angle software measurements.
The different results are based on the different fitting models used. Theta c is based on a circle drop (the ideal case), Theta e is based on a elliptical drop (non-ideal) and Theta Left and right are based on something else that i cannot explain here(least ideal).
@@yoyoerx how do you know what theta c , e etc. is based on, what are your sources? do you have a paper about this method? because i couldnt find any informations online.
@@croschko all of what I know is from the source code for the plug in. You can extract it from the jar file. It's partially commented in English and Italian. It has been many years since I last used it, so I don't recall all the specifics. I hope you are successful in figuring out what you are looking for.
Does it ever really matter if you don't know the actual diameter of the droplet in these calculations? I've used a similar ImageJ plugin, and there's an option for scaling (probably used in other calculations). However, provided the droplet isn't too large s.t. it deforms under it's own weight, the size is inconsequential to determining the contact angle, correct?
You are correct. Size does not matter unless it's so big it is "pancaking" out due to gravity. Smaller drops are better for that reason, but can suffer from more rapid evaporation and result in receding contact angle rather than static.
I am coming a little late to the party (its 2021) but I hope you can still answer my question - how do you use the data collected on contact angles to find the surface energy? Can Imagej help with this also? Thanks
Typically, contact angles for several liquids of different surface tensions are collected to form a Zisman Plot. Analysis of this plot compared to Young's Equation is used to determine the surface free energy. You cannot perform the analysis in imagej but you could use Excel or a calculator and graph paper. Hope this helps!
Hi yoyoerx, First of all, thank you for this nice video. But, comparing the Contact Angle plugin with the drop_analysis plugin, using the image sample from drop_analysis plugin, the results do not agree. Could you check and revert to us? Thanks!
Hello, Thank you for this video helping me to install the plugin. Nevertheless, I don't understand your results for theta C. The plugin gives you 101.5 but your angle, as far as I can see on your original image is lower than 90°. Could you please comment on this value ? Where is theta C located on your image ? Thanks a lot and enjoy climbing ;)
The fitting program is written assuming that the drop photo is upside down. Because it is not in my example, the data returned in the table is off by 180 or 90 degrees. Keep that in mind when fitting to the standard Young-Laplace Equation.
If you are opting manual points procedure, check for theta C (circle) or theta e (elliptical). Let me know if you find any tutorial/write-up for this algorithm. I am trying to get in touch with the author but his email is not working.
Firstly, thanks that was certainly helpful but perhaps you or someone else having used this plugin can shed some light on the statement on the plugin description page: "In our plug-in the image analysis works offline; it means that an image database is required. After a picture is loaded, the drop profile is detected. It is important to remind that the program was written supposing the drop is upside down. The reason is that our images are obtained by a camera connected to a microscope and the final picture is reversed up/down." I have tried using images other than the one given as sample (which is upside down) to see how accurate the measurement is and I do get a different value. when the image has a droplet right way down. I have also looked at other published papers where they have images with CA measurements listed and then tried comparing what I get with this plugin using their images and my readings are very different. Not sure what I am missing.
Hey, I know it's been two years, but I'm currently using this software and plugin. From my understanding, if you don't put your picture "upside down" the angles that you get are not the right angles, and you need to subtract 180 degrees from the results. Let me know if you think I'm right, Thanks :)
@@ilankachler hi buddy, i have the same request, ¿do you substract of your values of thetha left or thetha right 180°?, because if i use only the tool angle, and I compare my results with those of contact angle, they are very close.
Theta C is contact angle based on a circle fit and theta E is based on an elliptical fit. In a perfect world, the drops should be circular, but gravity and other effects will distort the shapes to ellipses. The preference is to use theta C unless you have a non-ideal drop (and, even then the data is suspect to some degree, based on the eccentricity).
@@yoyoerx do you have to substract either theta c or theta e from 180 degrees to get the contact agle? Or are they already the contact angle? Also, I've done some trials with imagej myself and theta c and theta e value are significantly different, like for example theta c I got 135 and theta c I got 51, do you have anh explanation of how that could happen? I'm sorry If I asked too many questions, your answer is very appreciated, thank you
If your drops are right-side-up, you need to subtract the results by 180° to get the proper contact angle result for typical Young analysis (the software was developed for drop photos that are up-side-down). If your thetas are that different, your drop could be highly elliptical (too big of a drop) or the fitting is not great. In general, the thetas should be fairly close.
I have long since left the position where I was doing this work, so I cannot completely walk you all through the setup. But, essentially it was a 40x microscope laid on its side with a bright LED and diffuser directly behind the drop to back light it. I hope this gets you going in the right direction.
Hi.. It was a very helpful video. I would like to ask you the radius it is showing in the result window is the base radius or the radius of the fitted circle?
Just realised that your desktop photo is the headwall of the lotus flower tower in the cirque! Wild, are you a climber? Did you climb that route? cheers.
Hello
Could you explain what output parameters mean, such as Angle, Length, Theta C, Uncertainty, Theta Left, Theta Right, Theta E, Radius, Circle StDev, Ellipse StDev, e, Points and Volume what they mean. Thanks
Hey great video. I wanted to know the difference between "Angle", "Theta E" and "Theta C"
Thanks for sharing🙏🏻
What kind of camera do i need to capture an appropriate image?
I just downloaded this program today (the day after you published the tutorial!) and was trying to figure out how it worked. Thanks for the straight forward, easy to follow video.
I am glad that was helpful for you. Make sure that the orientation of your photos is correct, the software assumes your droplets are upside down and will give you a reading that is off by 180° if they are oriented like mine.
You mention making surface energy calculations after calculating all your angles. You have a plug in or tutorial on doing that?
Hi thanks a lot for your videos it was helpful, but actually i am confused with the results. the true value of theta should be 180° minus the value shown in the results window right? thanks a lot in advance, hope you wound see it. best regards
I got confused about the same thing...
something wrong I did the same and the contact angle is 178 but the reality i know for fact my angle is not even more than 70 ?
Thank you so much for your step by step instructions. This was most helpful. Thanks.
Hi!! This video was so useful for me. Clear instructions. Well-done!! Thank you so much......
should I use circle fit or eclipse fit when both theta returns >130 (or a contact angle smaller than 50)
Could you please do a video on taking that photo
Thanks for the video. This is my first time of using image J for contact angle measurement. Please which of the thetas' are the advancing and receding contact angle? Thank you. I look forward to hearing your feedback as regards my question.
Thank you for your comment. The ImageJ plugin is only used for static drop analysis and cannot do advancing or receding angles. ThetaC provides the circle based contact angle which works well for ideal drops. The other theta's provided are based on elliptic fits and can account for asymmetric drop formation, but are further removed from the simple Zisman analysis. I hope this helps.
why is my tangent lines always intersect i dont know wha to do
Hey yoyoerx,
Could you also explain other terms too? I mean "angle", theta left", "theta right". Any tutorial that may suggest for this particular plugin. Thanks
have you figured out what these terms mean?
From what I could gather is that the theta left and right refers to the angle from both sides of the droplet as is the case with other similar contact angle software measurements.
Hi, it seems the CA showed in the pic is less than 90 deg, but the results are larger than 90 deg, may i know why? thx!
i think in the description of the plugin it says, that the picture of the drop has to be upside down, thats why the CA is not right in this video.
@@ikillaaaful thanks!
Hi. Thanks a lot for the video. I would like to know more about the sheet resuts. Do you know how to find out?
Hello is there an explanation, what Theta c, Theta left, Theta right, Theta E is?
The different results are based on the different fitting models used. Theta c is based on a circle drop (the ideal case), Theta e is based on a elliptical drop (non-ideal) and Theta Left and right are based on something else that i cannot explain here(least ideal).
@@yoyoerx how do you know what theta c , e etc. is based on, what are your sources? do you have a paper about this method? because i couldnt find any informations online.
@@croschko all of what I know is from the source code for the plug in. You can extract it from the jar file. It's partially commented in English and Italian. It has been many years since I last used it, so I don't recall all the specifics. I hope you are successful in figuring out what you are looking for.
@@yoyoerx okay thanks, i will have a Look at the source Code
CAN YOU SHOW IT WITH AN ARROW WHICH ONE IS THETA C on the image?
Can it analyse an image taken from mobile.
Hey great video! May I ask how you took those pictures up close of those droplets? I am trying to photograph them myself, but of no avail.
microscope
Does it ever really matter if you don't know the actual diameter of the droplet in these calculations? I've used a similar ImageJ plugin, and there's an option for scaling (probably used in other calculations). However, provided the droplet isn't too large s.t. it deforms under it's own weight, the size is inconsequential to determining the contact angle, correct?
You are correct. Size does not matter unless it's so big it is "pancaking" out due to gravity. Smaller drops are better for that reason, but can suffer from more rapid evaporation and result in receding contact angle rather than static.
@@yoyoerx after all these years, you replied. You’re a G!
Great video !
Also, does someone know the quantity the "Uncertainty" column relates to ?
I am coming a little late to the party (its 2021) but I hope you can still answer my question - how do you use the data collected on contact angles to find the surface energy? Can Imagej help with this also? Thanks
Typically, contact angles for several liquids of different surface tensions are collected to form a Zisman Plot. Analysis of this plot compared to Young's Equation is used to determine the surface free energy. You cannot perform the analysis in imagej but you could use Excel or a calculator and graph paper. Hope this helps!
@@yoyoerx thanks yes it helps.
Hi yoyoerx,
First of all, thank you for this nice video.
But, comparing the Contact Angle plugin with the drop_analysis plugin, using the image sample from drop_analysis plugin, the results do not agree. Could you check and revert to us?
Thanks!
Hello, Thank you for this video helping me to install the plugin. Nevertheless, I don't understand your results for theta C. The plugin gives you 101.5 but your angle, as far as I can see on your original image is lower than 90°. Could you please comment on this value ? Where is theta C located on your image ? Thanks a lot and enjoy climbing ;)
The fitting program is written assuming that the drop photo is upside down. Because it is not in my example, the data returned in the table is off by 180 or 90 degrees. Keep that in mind when fitting to the standard Young-Laplace Equation.
Great Video, can i ask if what is the Contact angle among all values shown on result box? Thanks
If you are opting manual points procedure, check for theta C (circle) or theta e (elliptical). Let me know if you find any tutorial/write-up for this algorithm. I am trying to get in touch with the author but his email is not working.
Firstly, thanks that was certainly helpful but perhaps you or someone else having used this plugin can shed some light on the statement on the plugin description page:
"In our plug-in the image analysis works offline; it means that an image database is required. After a picture is loaded, the drop profile is detected. It is important to remind that the program was written supposing the drop is upside down. The reason is that our images are obtained by a camera connected to a microscope and the final picture is reversed up/down."
I have tried using images other than the one given as sample (which is upside down) to see how accurate the measurement is and I do get a different value. when the image has a droplet right way down. I have also looked at other published papers where they have images with CA measurements listed and then tried comparing what I get with this plugin using their images and my readings are very different. Not sure what I am missing.
Hey, I know it's been two years, but I'm currently using this software and plugin. From my understanding, if you don't put your picture "upside down" the angles that you get are not the right angles, and you need to subtract 180 degrees from the results.
Let me know if you think I'm right, Thanks :)
@@ilankachler hi buddy, i have the same request, ¿do you substract of your values of thetha left or thetha right 180°?, because if i use only the tool angle, and I compare my results with those of contact angle, they are very close.
What's the difference between theta c and theta e in terms of use? Which one do you choose and why?
Theta C is contact angle based on a circle fit and theta E is based on an elliptical fit. In a perfect world, the drops should be circular, but gravity and other effects will distort the shapes to ellipses. The preference is to use theta C unless you have a non-ideal drop (and, even then the data is suspect to some degree, based on the eccentricity).
@@yoyoerx do you have to substract either theta c or theta e from 180 degrees to get the contact agle? Or are they already the contact angle? Also, I've done some trials with imagej myself and theta c and theta e value are significantly different, like for example theta c I got 135 and theta c I got 51, do you have anh explanation of how that could happen?
I'm sorry If I asked too many questions, your answer is very appreciated, thank you
If your drops are right-side-up, you need to subtract the results by 180° to get the proper contact angle result for typical Young analysis (the software was developed for drop photos that are up-side-down).
If your thetas are that different, your drop could be highly elliptical (too big of a drop) or the fitting is not great. In general, the thetas should be fairly close.
@@yoyoerx thank you so much for your answers, your tutorial also helps me to install and understand the contact angle feature 😁
hey this is a great video. I was wondering may be if you could demosntrate how have you taken the image and give details about thepicture
I have long since left the position where I was doing this work, so I cannot completely walk you all through the setup. But, essentially it was a 40x microscope laid on its side with a bright LED and diffuser directly behind the drop to back light it. I hope this gets you going in the right direction.
Hi.. It was a very helpful video. I would like to ask you the radius it is showing in the result window is the base radius or the radius of the fitted circle?
In the manual points procedure, It is showing the radius of the fitted circle.
Just realised that your desktop photo is the headwall of the lotus flower tower in the cirque! Wild, are you a climber? Did you climb that route? cheers.
Perfect for the install, thank you.
Thank you so much for the great video. It is quite easy!!!!
thanks
Wow thanks a lot