Image Definition and 1000 Threads

  1. N

    Mirror placed horizontally between two half convex lenses

    So I was able to find out quite easily the image distance after the first refraction and the corresponding magnification. Employing Cartesian convention ##1/v - 1/u = 1/f## Substituting the values gives us: ##v_1 = +60cm ## ## m_1 = -3 ## Thus the height of the image below the principal axis...
  2. Zayan

    Ray optics: velocity of image reflected off a moving mirror

    Using equation, Vm=(Vo+Vi)/2; 2= (4+Vi)/2 =>Vi=0. I.e, image velocity is zero. I can't understand how it is possible that the image is at rest wrt ground. If the object moves with more velocity than the mirror, wouldn't it collide with the mirror at some point? And plus the object is moving 2m/s...
  3. hraghav

    Find the location and length of the final image

    So I found the location of the image of the object produced by the mirror to be -58.2628 cmi^ and the length of the image of the object produced by the mirror to be -9.40012 cm. (these are correct values). To find the location of the final image of the object as produced by the lens I used 1/f...
  4. S

    Unable to crack this image enhancement code -- Matlab is throwing errors

    img= imread('Image.bmp'); img= rgb2gray(img); imshow(img); pt = ginput(4); % the function ginput is used to get the input from mouse x1 = pt(1,1); y1 = pt(1,2); x2 = pt(2,1); y2 = pt(2,2); x = [x1 x2]; y = [y1 y2]; line(x,y); x3 = pt(3,1); y3 = pt(3,2); x4 = pt(4,1); y4 = pt(4,2); x = [x2 x3]; y...
  5. L

    Is This Electric Field Representation Accurate?

    I have attached an image of what *I think* the electric field looks like. Would this be correct? I am convinced about everything here, apart from the ones on the far right. All the other ones loop from the +ve charge to the -ve charge, but where do the grey lines on the right loop to (the ones...
  6. Dr Wu

    Microchip Imaging: What Magnification is Needed for Electron Microscopy?

    Assuming the use of an electron microscope, what magnification would be needed to image a computer microchip at the micrometer level? Thanks in advance.
  7. T

    I Help identifying this Tumbling object in a night sky photo from Namibia

    I have received this image from someone in Namibia recently at the Kiripotib Astrofarm. Has anyone an idea what could cause such a strange trajectory?
  8. T

    I How can tomographic image resolution be obtained using wifi sensing and imaging?

    hello i would like to ask how to obtain tomographic image resolutions from wifi sensing and imaging using signals processing. thanks very much.
  9. pinball1970

    B AI Enhanced image of M87 black hole

    https://iopscience.iop.org/article/10.3847/2041-8213/acc32d From the abstract, "We present a new reconstruction of the Event Horizon Telescope (EHT) image of the M87 black hole from the 2017 data set. We use PRIMO, a novel dictionary-learning-based algorithm that uses high-fidelity simulations...
  10. L

    B Does light ever go from the eye to the image?

    You can see from the picture that the teacher has circled the arrows which shows light coming from image to the eye, and drew it in the opposite direction saying the light goes from the eye to the image. The marking scheme of this paper only says the correct direction does not specify which is...
  11. sHatDowN

    Vector-Force image and resolve force

    The components of the force of 800 lb F along the non-perpendicular axes Get a, b. Also determine the image F on the axes a, b could some one help me how to resolve forces non-perpendicular.And also what is the meaning of image F one the a,b axes
  12. Salmone

    I How does an eye reconstruct an image?

    I would like to understand the relationship between the image formed on the retina and the image reconstructed by the human eye. Let's consider this images: The object B forms the real image OB' while the object A forms the real image OA' on the retina. Second image: here, the object forms a...
  13. anorlunda

    I JWST Image Reveals Processes Ejecting Material in Star Formation

    Thanks to the JWST, we have this stunning picture. The APOD description says What are the processes that eject material at this stage?
  14. M

    How could you see an image without photons? (imaging systems)

    What kind of imaging system could be used to see without photons? I ask because I was watching a video and the furthest we can see back is Redshift Z~1090 which is the CMB. We can’t see the universe before the first stars formed or the Big Bang itself. My first guess would be some kind of dark...
  15. A

    I Image appears outside of q -- Lens Maker's Equation confusion

    Summary: Does the image distance q in the lens-maker's equation mean where real images form or where any image at all forms? If the former, what separates the real image from all other reflections? Hi all, I attached a series of images taken with a camera for a concave mirror, the Pasco...
  16. M

    React - load new image - error - part 2

    It works with this code! If I want to write a text next to the image do I use <div> ? I mean : return <div><div><img src={logo} alt="Logo" width="40" /></div><div>Title</div></div>; 🤔
  17. M

    How to Correctly Load a New Logo in React?

    Hey! :smile: I need some help in react. I have a code for a web application and I want to change the logo. The logo I want to use is in the public folder, in this folder there is also a favicon with the old image. In the src folder there is a folder images with the old image. In the src folder...
  18. Aymangh994

    I Using simple lenses to image AFM Probes

    Hello, Using a CCD camera and simple lenses, the probe of the cantilever and its surroundings are to be imaged. Since the cantilever is 50 um wide and some of the surroundings are to be imaged, the optimal image magnification is from 4 to 8. I therefore used a convex lens with a focal length of...
  19. Bob Walance

    JavaScript Button click event image hiding is delayed

    My webpage project has a button labeled 'Harmonics' with a mouse-click event. I want an image to be hidden as soon as the button is clicked, however this doesn't happen. Here's a snippet of the html. It doesn't matter what order the two Javascript functions are called. The 'hidden' attribute...
  20. A

    Is this vector in the image of the matrix?

    Hello! I have this system here $$ \left[ \begin{matrix} -2 & 4 & \\\ 1 & -2 & {} \end{matrix} \right]x +\begin{pmatrix} 2 \\\ y \end{pmatrix}u $$ Now although the problem is for my control theory class,the background is completely math(as is 90% of control theory) Basically what I need to...
  21. L

    Image position and magnification for underwater spherical lens

    Using the data given and recalling that in this configuration ##R<0## I get: ##\frac{1.33}{0.5}+\frac{1.5}{q}=\frac{1.5-1.33}{-0.2}\Rightarrow q\approx -0.427 m=-42.7 cm## so the image is virtual and is ##42.7\ cm## to the left of vertex ##V##. The magnification is ##M=\frac{n_1 q}{n_2...
  22. B

    Understanding the Basics of FFT for Image Processing

    if you watch this Video : The Julia Programming Language at time marker 28:00, You will see that Grant takes an FFT of an Image. In order to do a FFT, you need to know the sampling rate, but what is the sampling rate of one image? And what if your image is not size 2^N ? Does the program just...
  23. N

    ART algorithm - Image Reconstruction

    My answer: The ART algorithm is a row-action algorithm. I tried to draw it, but I am not sure whether it will answer the question
  24. DhruvSorathiya

    I Could the Sun burn an image sensor of a star tracker in space?

    Hello, I have a question. If a star tracker in space faces the sun directly then could it be possible that the sun completely burns the image sensor? To be specific we are a student satellite team (Student satellite program IIT Bombay) developing a star tracker and we don't have an exact idea...
  25. rishurboi

    I Applications of Virtual objects

    I've heard virtual objects are used in cinema halls I'm not sure of what that means, can someone explain this to me please? And btw by virtual object i mean when diverging rays from real object passes through a convex lens, the rays will converging and if you'll place a plane mirror infront of...
  26. dom_quixote

    I Uncertainty in an experiment with an image viewed through a big slit

    This is a simple experiment that demonstrates how it is possible to draw conclusions similar to those of quantum physics, without having to "invade" the microscopic world. A student is led into a windowless room, which has only a slit in the ceiling. The light that passes through the slit is...
  27. cianfa72

    I Maps with the same image are actually different curves?

    Hi, I've a doubt about the definition of curve. A smooth curve in ##\mathbb R^2## is defined by the application ##\gamma : I \rightarrow \mathbb R^2##. Consider two maps ##\gamma## and ##\gamma'## that happen to have the same image (or trace) in ##\mathbb R^2##. At a given point on the...
  28. samy4408

    I What does "upright" mean in geometric optics?

    if someone want to explain to me what is an upright image ? , and what are the other adjectives to define an image in geometric optics and their meaning , Thanks .
  29. A

    New Olympic games Logo Designs -- Can Machine Learning help?

    Olympic games logo We have the beautiful logo designed for Olympic games. Five rings of different colours each representing the Continent. Significance of friendship between all continents. Countries representing the Olympic games from various continents. Questions 1 The Origin of this Olympic...
  30. Physics_learner

    Kinematics - can't find the initial velocity according to the image

    I tried to write the data I understood from the image: y0=160m yf=0 x0=0 x1=192m I tried to express the total change in time using the position over time equation on the Y direction: y(t)=y0+v0y*(t2-t1)-0.5a(t2-t1)^2 but then I stuck with 2 variables and didn't know what to do any help?
  31. ergospherical

    Which Program Can Help Analyze Distances Between Features in Images?

    I have taken some photos (with my phone) of some optical phenomena in the lab. I'd quite like to analyse the distances between some features of the image. In school I remember using a piece of software which allowed you to choose an origin point / setup coordinate axes, select a scale (i.e. 1 cm...
  32. B

    Image processing with Sobel Edge detection

    I am coding Sobel Edges detection in C#. I have a method that converts my image to grayscale. it adds the R G and B values and divides by 3. and replaces the R G and B value out with that same number. That seems to be working fine. Then I added a gaussian blur to it by using this...
  33. A

    Image comparison software (similarity and differences)

    Images comparison What are the best softwares available for comparing two images having similarity and differences? Two photos each of Margaret and Enid. 1 Margaret's first photo with her second photo comparison. 2 Enid's first photo with her second photo comparision. 3 Margaret's first...
  34. M

    Machine learning with image tracking of a line

    Hi PF! At the bottom of a transparent cup full of water is a hole where water drains. The cup is sloshed, so the gas-water interface is not flat. Are there any techniques you're aware of that implement machine learning to track the interface? My current technique not using ML is: 1) splice...
  35. pellis

    I How should we interpret the Möbius-strip image of spinors?

    On first coming across the Möbius-strip image of spinors, it seemed natural to interpret it as referring to the 3D space of everyday experience, especially as e.g. the Dirac belt and the Penrose book demonstrations appear to occur ‘naturally’ in the world of our phenomenal experience. Doubts...
  36. L

    Position of the image of an object placed in water

    I tried using the formula for the refraction of a spherical lens ##\frac{n_1}{p}+\frac{n_2}{q}=\frac{n_2-n_1}{R}## consider each slab as a spherical lens with curvature ##R=\infty## and by doing that I get ##\frac{1.33}{10}+\frac{1.5}{q}=0\Leftrightarrow q\approx -11.3 cm##. Since the piece of...
  37. DMAJones

    Can I get some help please? (single image display)

    first of all- Hello! I was wondering if anyone can help me, I am looking to get a miniature display (2.8" TFT display, annoyingly touch screen but oh well) all I want to do is display a single image for a small project of mine but I'm not sure how to approach this, do i use a RaspberryPi or...
  38. S

    Can twin cats have mirror image fur colors?

    Is it possible for monozygotic twin cats to have fur colors that are mirror images of each other? Or does such mirror imaging rule out that two cats are monozygotic twins? In searching for images of "twin cats" on the web, I find a few photos of pairs that have mirror image fur colors. For...
  39. Mikkel

    Deep Learning for Image Recognition in Astrophysics

    Summary:: I'm looking for some great books on deep learning related to image recognition that I can use in astrophysics. Hello, I'm about to start my master thesis, where I, in short, will be comparing snapshots of young binary stars from simulations to observations using deep learning -...
  40. H

    I Image for increase in gravitational potential energy in radial field

    A question to physicists: What sort of real world scenario / image would *best* depict the increase in gravitational potential energy in a radial field? Would a rocket traveling through the Earth's atmosphere suffice or are there better alternatives? This image would have to be relevant to the...
  41. M

    Mathematica Saving an image in a for loop with an updated name

    Hello all! I am trying to export image0, image1, image2, etc in a for loop. What I have is For[i = 0, i < 4, i++, "image" <> ToString[i] = Rasterize[plfunc3dANGside2[6, 2, 115, 0.1*i], Background -> None, ImageResolution -> 1000]; Export["/home/josh/ISS_drops/vibrations/" <> "image" <>...
  42. rinalai

    [HW question] Image size difference of two light emitting nanospheres

    I wonder if this question is about two-point resolution or magnification... Would someone here be so kind as to offer some guidance on this question? Thank you!
  43. Dario56

    I How Do Electromagnetic Lenses Magnify the Image?

    In optical microscope both objective and eyepiece are used to magnify the sample image. Magnification is determined by laws of geometrical optics (intersection of optical beams from the same point of the sample) In electron microscope, electromagnetic lenses are used to magnify the sample...
  44. DaalChawal

    MHB Taking Image of a curve about a given line

    How to find image of $f(x)= x + sinx$ about the given line $y = - x$ . Similarly can we take image of a function about a function? OR is it necessary about which we take image should be a point, line only?
  45. dRic2

    GNUplot -- how to improve image definition?

    Hi, I am used to plot data with the GNUplot software. This time I need to add an image to my plot. I did with the following line 'my_image.png' binary filetype=png center=(3.25,-9.1) dx=0.007 dy=0.0125 w rgbimage notitle but the final resolution of the picture is pretty bad compared to the...
  46. G

    A Image Method for B-Field Calculation on Iron Plate

    Hello, I am wondering if it is possible to calculate the B-field of a conductor above an iron plate just using the complex image method. To keep it simple let’s consider a 2D calculation, the metal plate is infinitely deep and wide and the conductor is infinitely long and thin. If the metal...
  47. A

    I Why do modern X ray images have better resolution compared to older ones?

    It just occurred to me while watching some old X ray images , what is the reason behind why modern X ray images have so much more detail than older ones especially really old ones from the beginning of the technology at the start of 20th century? I ask this because (unlike in a CT scanner which...
  48. Eclair_de_XII

    If the inverse image of the image of a set via some function is equal....

    ##A=(-1,1)## ##B=[0,1)## Define ##f:A\longrightarrow B## by ##f(x)=x^2## Set ##X=A##. ##f(X)=\{f(x):x\in X\}=\{x^2:x\in(-1,1)\}=B## ##f^{-1}(f(X))=\{x\in A:f(x)\in f(X)\}=\{x\in (-1,1):x^2\in B\}=X## Now choose a non-zero point ##y\in f(X)##. There are two pre-images of this point: ##x,-x\in...
  49. S

    I (See image) At what distance does the temperature of the Corona decline?

    My astronomy textbook includes this graph of the temperature of the Sun's Corona versus the distance above the photosphere. It appears to go up from 4,500 K to over 1 million K at 20,000 km above the photosphere. But at what point does it come back down? Or does it not? Does that mean the...
  50. M

    MATLAB Can I make my figure annotations even bolder?

    Hi PF! I'm trying to get the annotations for the plot save as bold. You can see the MATLAB window appears bold: but the latex output is normal: Is there a way to make annotations on figures even bolder than the standard bold setting?
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