Image Definition and 996 Threads

We all heard about the "photo of black hole". My question is: did this image show any hints of physics beyond general relativity? I read once (not sure where) that the apparent size of black hole shadow is very sensitive to corrections to general relativity. Add some minor correction and the...

Lobes Did anyone hear an explanation of the appearance of the lobes visible in the published image? I only caught part of the Q&A. (Visible most prominently at at eleven o'clock and four o'clock positions, and to lesser degree at three and nine) Do these type of observations generate "lense...

There is an original image test1.jpg. The problem is to show axes in the image and retain image quality. I am running the following code: img = imread('test1.jpg'); % define variables imgsize1 = size(img,1); % size on screen imgsize2 = size(img,2); xreal = 1; % meter yreal = 1; %...

First of all, Let me present some of the things I found from research. (considering convex lens) Interpretation 1 => Focal length is the distance from the center of the lens to the point where all rays converge. Interpretation2 => Focal length is the distance from the point of convergence to...

Homework Statement A charge q is kept at distance d from center of grounded conducting sphere of radius R. Find V everywhere outside. Homework Equations V = k*q/r Cosine Law. The Attempt at a Solution [/B] What do I do with the theta? And how would I analytically find out what Q and b...

Homework Statement Homework Equations The Attempt at a Solution I'm sure my solution is wrong because of Φ(z=0) ≠ 0 I searched the internet for a similar problem but I couldn't. Any help will be appreciated.

The Hubble deep field image was constructed by collecting photons from a specific region of space over a continuous duration of time; in this case ten days. As the number of collected photons increase, higher the resolution of the image. If this duration increases, how much more resolution do...

Do Prism form image? If they do form image, then what is the nature of the image formed?

Homework Statement Find induced charge density in the classic image problem. Sorry, I uploaded my work in form of an image instead of typing. I have tried to use polar coordinates to solve this. But i must have done something wrong. Please help me find the mistake.

Is it possible to get a real image of virtual objects, If so please explain with examples and some real life situations? Look at my assertion "rays will not pass through virtual objects so how it can form real image", is this possible, please help.

In this CERN video quarks are represented as spheres. Is this how quarks look like. I thought they were fluctuations in the quantum field.

Homework Statement Find a function where the domain is integers, codomain is real numbers, and image isn't equal to codomain. Homework EquationsThe Attempt at a Solution I know that it means that when I plug in an integer I will obtain a real number, but how do I make it so that the image is...

Homework Statement When comparing image sizes of the hotter stars with the cooler stars, do hotter stars consistently appear larger in one image and cooler stars consistently appear smaller in the other image? Why or why not? Homework Equations Stellar Spectra Classification[/B]The Attempt...

I'm looking for images of electron or ion beams recorded (from the side) using electrons, for example with a transmission electron microscope. Does anybody have references to publications?

Suppose light rays from an object fall perpendicular to the surface of the plane mirror. Will the image be formed at +infinity(a virtual image) or -infinity(a real image)? I will be thankful for help!

I just recently found this zoomable image of the milky way and I have been really curious about what the 2 really bright spots are. There is one in the bottom left corner and another near the bottom center. https://www.eso.org/public/usa/images/eso1242a/zoomable/

Can someone please tell is this (https://ibb.co/stGFSKs) figure a polygon. If yes then is the middle line would count as an edge?

I have the next function: f(x)= -2(x+1)/(x-1)^2 x is from [0,1)U(1,3] I need to find the image of the function which is (-infinity, -2].I tried with the derivative but when I solve f'(x)=0 I obtain x=-3 which is not from x interval.I don't know how to continue.

Homework Statement The physical size of a single LOFAR station, operating at 150MHz is about 50m. Estimate the number of pixels which would be needed to map the full primary beam if one wished to include all LOFAR stations (maximum baseline ~ 800 km) at full resolution. Homework Equations...

I created this thread because every online resource I have examined to date has been largely worthless- either totally over-engineered complexity or superficial garbage (can you tell I am irritated?). The problem is simple: optimize DSS image stacking and post processing based on quantitative...

Homework Statement [/B] This problem is from Mark Newman's Computational Physics, problem 7.9, found at http://www-personal.umich.edu/~mejn/cp/exercises.html. The problem gives us a blurry convolved image, according to a Gaussian point spread function and our objective is to deconvolve it to...

Homework Statement A mirror is moving to the right with a velocity 15 m/s, and an object is moving to the right with a speed of 5m/s. All speeds are wrt ground. Find the velocity of image wrt ground. Homework EquationsThe Attempt at a Solution I present to you two probable solutions: 1) Using...

Homework Statement My question is, are real images always inverted and virtual always erect? Homework Equations 1/v+1/u=1/f for mirrors and 1/v-1/u=1/f for lenses The Attempt at a Solution Consider a concave lens, with object at -x. the condition for a virtual image is v<0; i.e on the same...

Homework Statement The focal length of a concave mirror is f=20 cm. It is directed towards the sun and the sun makes an angle= 1° at the pole of the mirror. What is the size of the image of the sun? Homework Equations 1/u +1/v =1/f ...(i) ,magnification= v/u= l2/l1 where l1 =size of the sun,l2...

Homework Statement Let ##f:\Bbb{R} \to \Bbb{R}## be a function such that ##f## has a local minimum for all ##x \in \Bbb{R}## (This means that for each ##x \in \Bbb{R}## there is an ##\epsilon \gt 0## where if ##\vert x-t\vert \lt \epsilon## then ##f(x) \leq f(t)##.). Then the image of ##f## is...

Homework Statement The following figure represent the traversal cut of a system with two cylindrical equal conductors of radius r0 length l at a distance d from one another and at the same distance h of a plane conductor (conductor zero). The dielectric that surrounds the conductors is the air...

URL: https://www.jssor.com/demos/image-slider.slider Is it possible to have a Image slider control which infinitely shows images after every 4 seconds delay but every image itself is a animated and not a static image? I.e Image Slider control showing animated images .gif,.jpg etc Thanks &...

O'Neill's Elementary Differential Geometry, problem 4.3.13 (Kindle edition), asks the student to show that the image of an open set, under a proper patch, is an open set. Here is my attempt at a solution. I do not know if it is complete as I have difficulty explaining the consequence of the...

Hey! :o Let $A\in \mathbb{C}^{2\times 2}$ and $L_A:\mathbb{C}^{2\times 2}\rightarrow \mathbb{C}^{2\times 2}, \ X\mapsto A\cdot X$. We consider the matrix \begin{equation*}A=\begin{pmatrix}-1 & 2 \\ 2 & -4\end{pmatrix}\end{equation*} and the basis \begin{equation*}B=\left \{\begin{pmatrix}1...

Is it necessary that the image of the point object placed on the axis of optical system has its image formed on the axis? Consider paraxial approximation.

Homework Statement See my attached information Homework Equations On my attached solution The Attempt at a Solution see my attached sheet Please see my attached write up. I would appreciate a quick nudge as stated.

A new planet has been visualized in a protoplanetary disk around a star. It's the bright thing at about 4 o'clock. Star (PDS 70) is blocked out. Science magazine news article here.

Hello everyone, I was wondering what would be the differences in case that we had to reconstruct a set of 80 kvp images vs a set of 80 kev images. I suppose that it would be faster in the first case since there would be less time needed since the attenuation coefficient would be fixed in the...

Hey! :o I want to show the following: Let $G \subset \mathbb{R}^n$ be open, $f \in C^1(G)$ and $\det J_f(x) \neq 0$ for all $x \in G$. Then $f$ is an open map, i.e. the image $f(O)$ of each open subset $O$ of $G$ is open. The following hint is given: Let $O \subset G$ be open. Apply at...

Hi all, I think I have an idea of how the Mathematical aspects of Face recognition work. But I am curious as to what an eigenvector would be in this respect. I am trying to understand it through finding out how pixels are encoded: What map takes a pixel into a collection of...

Homework Statement This isn't really a homework, but I am trying to figure out how this would work. I have an plano-convex lens with an focal length of 500 mm. I have an laser source that I like to focus on, to the infinity. I.e. I like to see the laser lobe. Case: What happens to image of...

Homework Statement Two lenses with the focal length of 50 mm are placed tightly. An object is placed 130 mm away from the lenses. Where is the image generated by the lenses? Homework Equations \frac{1}{a}+\frac{1}{b}=\frac{1}{f} L = f_{ocular} + f_{objective} The Attempt at a Solution...

Homework Statement Homework EquationsThe Attempt at a Solution I have solved this problem . For that I had to use refraction at the first surface , then reflection from the back side and then again refraction from the first surface . This gives me the correct answer . But when I saw the...

Homework Statement You look at yourself in a shiny Christmas tree ball, which has a diameter of 9.63 cm. If your face is 7.81 cm away from the shiny ball, calculate the image distance. Homework Equations ? Thinking I would use magnification = di/d0 di = 0.0781m d0 = 0.0963m The Attempt at a...

Is there a simple way to determine or prove this? Real images are always inverted, and unlike virtual images can be projected onto a screen (I'm not even sure what this means to be honest). If I look at the back end of a spoon (convex mirror), the image is always upright and therefore virtual...

Hi, I am doing research in content based image medical image retrieval using radon barcodes. I have replicated an approach found in this paper 277011226_Barcode_Annotations_for_Medical_Image_Retrieval_A_Preliminary_Investigation. I have tried to make some improvements to this process regarding...

Homework Statement Homework EquationsThe Attempt at a Solution I have placed the origin at the middle of the mirrors . This means object is at the origin . Now I am bit unsure about what the question means with 5th reflection .I am assuming that it means 5th image in either of the mirrors...

I just an read article on the ESAs Gaia program. I was wondering how they count the 1.7 billion stars in the image? Are the stars cataloged as the images are taken? Or is there a method that is used after the images have been collected? http://sci.esa.int/gaia/60169-gaia-s-sky-in-colour/

General question regarding how images are formed. As you move your eye "detector" around a illuminated room. The is image of let's say "a book" is in every position in the room at a given time correct--even before you "look" at it? The photons reflected off the book have formed an image of the...

Homework Statement What diameter will have an image of the Sun (α=32’) projected in the focal plane of a f/7 lens with a focal length of 40 cm? What will be the luminous flux in the image? Homework Equations image diameter = α×f focal ratio = f/D 1 radian = 206265’’ The Attempt at a Solution...

Homework Statement In the picture 20.40, what is the direction of the current induced in the resistor at the instant the switch is closed.[/B]Homework Equations Right hand rules- Point thumb in direction of current and your fingers will curl in direction of magnetic field. Lenz's law. The...

I am experimenting with a CIS from a document scanner (basically a row of photo sensors). I want to detect the position of an object as it passes the scanner bar. Initially in one dimension - x along the CIS. If the object is always a set distance from the light bar, I can provide illumination...

On this wire grid polarizer the wires are less wide than one wavelength of the incoming radiation. Is it possible to achieve a specular reflection from a single wire as shown on the image? What about reflection in the plane of length of the wire and the plane perpendicular to it (as shown)? Or...

From https://phys.org/news/2018-01-image-hubble-cartwheel-galaxy.html The attached article explains the proposed origin of this nifty ring galaxy.

Hi colleagues, I need your help to figure out some subtle theory problmes I have about this topic. I was thinking about a system composed by a conductive sphere (not grounded) under the effect of a pont charge placed near the sphere. As I know we need two image charges to satisfy the boundary...