Ccd Definition and 49 Threads

I was thinking about how CCD's and CMOS's almost exclusively come in multiples. To be clear, what I am referring too is how each chip is fabricated to feature many pixels. Does the fundamental unit of a CCD/CMOS have a name "commercially"? Something like a "single pixel camera"? Looking at...

I think this is a simple request but I’ve never been very good at optics and need help. I have a ccd video camera with a fixed lens. Images are in focus from about 20 cm to infinity. It has an angular fov of 60 degrees. Can someone explain how to add external lens(es) to magnify a plane image 4...

Hey all. I tested my astro camera a while back and found what looks like a temperature dependent readout noise value. Which is odd, as everything I've ever read has told me that readout noise is independent of sensor temperature. I took 50 bias frames at 5°c intervals, from -15°c to +20°c and...

I don't know if this is the appropriate forum for it. But I'd like to understand the concept of counts per frame in CCD in visible or IR spectrometry. If the exposure is say 200 ms and there are 12 frames. What is the counts per frame? Do you multiply 200ms by 12 frames to come up with 2400...

This is assignment related, however it’s not really a problem solving question. So we were to take darks from our school’s CCD. The manual for the CCD says there should be ~1000 ADUs/pixel for the bias, my graph (as well as many other people- they had similar numbers) says that the bias should...

(Sorry for Length) 1. Homework Statement You have decided to use a CCD camera to check if a 16th magnitude quasar is variable. You can presume that all of the light of your quasar falls on one pixel. You know that a star with a magnitude of 0 would deliver 1 × 10^9 photons/second to one pixel...

Homework Statement You have decided to use a CCD camera to check if a 16th magnitude quasar is variable. With your telescope/camera combination, you know that a star with a magnitude of 0 would deliver 1 × 109 photons/second to one pixel, so this allows you to work out the photons/second from...

Dear friends I am new at this forum thank you for accepting my application first of all. My question is that I don't understand the optics/physics behind the reason why Si-based CCDs are not sensitive for IR-light (above 1000-1100 nm) if on the top of the p-type Si there is a SiO2 layer which...

Is the monetary savings in buying a cheap CCD (£10-£250) outweighed by the performance of an expensive CCD (£700+)?

I have read the textbook but it does not explain it in a very intuitive manner. This is the explanation (the bolded bits are the unintuitive bits): Rectangular electrodes and an insulating layer are thin enough to allow light photons to pass through and liberate an individual electron in the...

If my understanding of the theory is correct, the fact that very low light is detected on a CCD at points demonstrates light's behavior as a particle. For, if light acted as a wave in this instance, we would see not points but vectors (lines) registered on the CCD, that is, representing entire...

Would such a telescope be useful for discovering new main belt asteroids: http://www.officinastellare.com/products_scheda.php?idProd=29

Hello guys, thanks in advance for the help. I have come across a theoretical problem which I hope you will be able to help me solving. It is all base on resolution (Rayleigh criterion) and Nyquist sampling theorem connected to camera capabilities. So, resolution (Rayleigh criterion) is roughly...

CCDs are very cheap, but I was wondering if there was an even cheaper alternative to CCDs if the goal is differential photometry on magnitude 5 and under stars. The data only needs enough precision to prove/demonstrate the concept, and to develop a good sense of the workflow in doing...

Hi, it seems astronomical FITS images are abundant on the internet. However, I am looking for FITS images of bias/flat and standard stars along with observations to practice CCD photometry and having a harder time. I would like to be able to take a set of images and obtain the transformation...

Hello, I need to learn as much as I can about single photon counting pixel detectors (producing a signal for each photons hitting the detector) e.g. PILATUS. I do not understand how this type of detectors counts single photons as opposed to integrating the energy of multiple photons (CCD, MOS...

I have a got a problem regarding what a CCD pixel actually measures. Suppose I have a pixel of area dx dy. A plane wave of intensity I0 is impinging on the pixel making an angle α with the normal of pixel surface. The flux going into the pixel would be F = I0 dx dy cos(α). My question what is...

Hi! I´m a dentist and I own a couple of surgical loupes... I´m a DIYer for the fun of it, but I´ve got a limited knowledge in physics... I´d like to adapt a CCD (I´ve got one from a webcam) to the eyepiece of my loupe´s ocular... So I can take pictures or even film what I´m seeing so I can show...

Hi, I have an experiment set up to get two beam interference fringes. I would like to know how I could measure the actual amplitude of the irradiance from the experiment. I have with me a power meter and a CMOS camera. How can I go about this? Thank you

I'm confused about optical low pass filters (found on CCD imaging devices). As I understand it is a double layer of birefringent material which in effect splits light into 4: (2*25%) green, 25% red, and 25% blue (for a standard bayer matrix). The part I'm not sure about is if all 4 fall on the...

Homework Statement I'm learning light interference and confused by the concepts. Like the figure I attached below, while computing the "interference" of the intersection point on the CCD, I used to do this ( E represents the electric field): E_{CCD}=E_1 \cdot e^{i (\omega t + \frac{2...

There are two telescopes observing at night. The first telescope is 0.3m and has a focal ratio of f/8. The second telescope has a focal ratio of f/4 and is 30m in diameter. They each have an identical CCD camera whose pixels are 25 microns on a side. How much energy will be accumulated in a...

I have astronomical images taken using a CCD camera and telescope using a g filter. In the images I have stars with what is called instrumental magnitudes (from the photon count in each pixel). My question is if there is a way to change this g instrumental magnitude to a real V magnitude. I...

Homework Statement A spectroscopist has a spectrometer equipped with a grating with 600 grooves/mm. This grating puts a 1228 nm wavelength range on a spectroscopic plate (a CCD) in order m = 5. The spectroscopist now changes the spectroscopic plate CCD by one that is larger by a factor of 3...

The question could be stupid,but It really confused me. when we capture spectroscopy using reflected grating and CCD, Does the diffracted light must be focused on the plane of CCD (using a plane grating),or it must be collimated to arrive the CCD.

Hey all. Looking at the following link http://starizona.com/acb/ccd/projectsfaint.aspx , the page says that limiting magnitude is mostly a function of aperture.(First paragraph in the Project Ideas section) I'm wondering why that is. Doesn't skyglow increase at the same rate as the light from...

Which is the preferred detector, the CCD chip or the Photodiode. What are the differences between these two?

In CCD detection, is integration better than accumulation Hi, I have carefully experimented and found this to be a true observation with CCD detection in general. Signal to noise improves if one integrates a signal (e.g. over x seconds) versus accumulating over many short integration times...

Hey Guys, i'm a first year astrophysics student and i got given this question to answer in a practical report: Examine the spectrum of the planetary nebula derived from the diffraction grating. You will produce a colour rendering of the spectrum together with a graphical representation of...

intuitively, i would say that in a CCD, the photoelectrons are being "created" only by the electric field of the incident light, so that the intensity is proportional to |E_x|^2+|E_y|^2, with the xy-plane coinciding with the CCD plane. But I have several papers here saying that the intensity...

I just link my microscope (Olympus CX31) with CCD (Sony), the staff 's company installed "Ulead program" in computer linked with CCD to capture the picture from microcope. The problem is when the picture shown in the computer, it is already too enlarged that we can't see the wider view as we...

Hi I have a problem to solve and I'm stack, so I would really appreciate your help if anyone can tell me how to answer the following question: "Consider a sky imaging system that has a 100m wide FoV measured at 1km from the camera; and that images a passenger airliner at a height of 2km as 10...

I'm looking for a small camera to use in my rocket. It's about a 7' rocket, 4" diameter and 3" long viewing window. I've heard that the choices are either cmos or ccd but I don't know the difference between the two. I'm only looking to spend up to $100 (really looking in the $50 range). Any...

Hello everybody, I have been searching for a linear image sensor CCD or CMOS for emission spectroscopic applications.The length and pixel size should be around 70mm and 8-12um respectively. Will somebody help me in finding this? Another one is It's 'camera card' or data acquisition...

Hi, I'm trying to find a high resolution ccd camera that can be used to take PHOTOGRAPHS to inspect the surfaces of metal cavities. It has to be compact and oblong to fit into a tube so it can be inserted into a cavity. I'm looking for something very much similar to this shape...

Hello, What are the important differences between CMOS and CCD? I am studying the digital cameras

I am working on a research project in which I will need to create a pattern of charge on the surface of a material. Could a CCD be run in reverse to create a pattern of electrons on its surface?

I am aware that for a CCD image to be produced, various corrections have to be applied due to the limitations of CCDs in astronomy. One such correction is the fact that CCDs are not perfectly linear since each detector pixel has a maximum size - it can only collect so many electrons. So...

Hello, I have two question regarding CCD camera technology. How is a dark frame(image) taken ? ( Is this simply the state of the pixel array when the shutter is in close position? How can one determine the camera efficiency as a function of energy from energy dependent measurements...

Hi, I have some question about the full well capacity and dynamic range of the CCD camera. The following link lists some full well capacity and dynamic ragnes of some CCD cameras: http://www.andor.com/learning/digital_cameras/?docid=321 My question is how they obtain the electron numbers...

I am learning about CCD s, and I always get the term BIAS, but I can't find any clear definition of what that is, can anybody help please? Thanks, Randa

How can I find the number of Rayleighs per count if I know the column emission rate, radiance, irradiance, #photons per pixel and #photoelectrons per pixel? I'm totally lost in this one, please help!

hi, I have ccd camera EDC-1000TE and i want how to interfcace with matlab thanks a lot sorry for my english

My question concerns what deep field objects you can see by eye using a quality 8" or 10" Cassegrainian scope? I understand that you can get some nice photographs with long exposures, but what about just looking through the scope? Planets are a given, but what about spiral galaxies, as an...

CCD readout noise problem! Hello all! does anyone know how to calculate the readout noise of a ccd? i have found values for proffesional and amateur ccds on the net but as far can't find any method of calculation. what does the value depend on? charge transfer time? number of electrons...

I've taken some images of faint asteroids that require 300 second exposures, and obviously I get a certain degree of blooming in most images. However, on images where there is a particularly bright star that star will have a black streak through it. Somebody did tell me that the CCD reading...

Hi I've just got a small problem that needs to be cleared here to allow me to do the other questions. Statement: Two objects were detected in a 100-sec exposure with 3x4 CCD camera Now you are given 3 by 4 matrices for the raw image data, bias, dark count and flat field. I've provided a link...

Hey, this is just a quick question on the quantum efficiency of CCDs. First of all, you are given the quantum efficiency of the CCD and the throughput value of the filter. So do you just multiply the throughput by the original quantum efficiency to obtain the quantum efficiency of the...

Hello everybody, I want to know the difference between CCD size like 1/2" and 2/3". I want information abt the various areas for which the above specifications are used. What exactly it means? Please if anybody can provide me with technical details i am thankful. thanks in...