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3d scanner for small objects image
marshyanke
I know that a spiral produces thinner slices and perhaps in more detail, I am not really sure? I would like to better understand the science behind it? Also, could you respond with some understanding of MRI and Doppler scans as well? Could you provide some of the history of the above mentioned diagnostic tests? Thank you.
Answer
Computed tomography (CT), originally known as computed axial tomography (CAT or CT scan) and body section roentgenography, is a medical imaging method employing tomography where digital geometry processing is used to generate a three-dimensional image of the internals of an object from a large series of two-dimensional X-ray images taken around a single axis of rotation. The word "tomography" is derived from the Greek tomos (slice) and graphia (to write). CT produces a volume of data which can be manipulated, through a process known as windowing, in order to demonstrate various structures based on their ability to block the X-ray beam. Although historically (see below) the images generated were in the axial or transverse plane (orthogonal to the long axis of the body), modern scanners allow this volume of data to be reformatted in various planes or even as volumetric (3D) representations of structures.
Spiral CT scanning is just a new and advanced from of CT scanning: This is a newer type of CT scan, also known as a 'helical' CT scan. It is faster than a standard CT scan and gives an even more detailed picture of your organs and tissues, including blood vessels. This can make it useful for picking up very small tumours. It's called a spiral scan because the X-ray beam rotates around you during the scan in a spiral shape. This gives the radiographers a continuous picture, with no possible gaps between the 'slices' of the scan.
Computed tomography (CT), originally known as computed axial tomography (CAT or CT scan) and body section roentgenography, is a medical imaging method employing tomography where digital geometry processing is used to generate a three-dimensional image of the internals of an object from a large series of two-dimensional X-ray images taken around a single axis of rotation. The word "tomography" is derived from the Greek tomos (slice) and graphia (to write). CT produces a volume of data which can be manipulated, through a process known as windowing, in order to demonstrate various structures based on their ability to block the X-ray beam. Although historically (see below) the images generated were in the axial or transverse plane (orthogonal to the long axis of the body), modern scanners allow this volume of data to be reformatted in various planes or even as volumetric (3D) representations of structures.
Spiral CT scanning is just a new and advanced from of CT scanning: This is a newer type of CT scan, also known as a 'helical' CT scan. It is faster than a standard CT scan and gives an even more detailed picture of your organs and tissues, including blood vessels. This can make it useful for picking up very small tumours. It's called a spiral scan because the X-ray beam rotates around you during the scan in a spiral shape. This gives the radiographers a continuous picture, with no possible gaps between the 'slices' of the scan.
How are 2D cartoons animated today?
Captain Ca
I understand how 3D images are made, they generate models and send them through animations. However, how do they do 2D cartoons? I asume they don't draw each individual frame anymore. But, backgrounds that don't move do appear to be hand-drawn in some shows. How do 2D cartoons go through animations?
Answer
Depending on the budget, deadlines, technology, experience and preference that 2D animations are made one way or another.
Small budgeted shows, destined for the weekly TV slots are mostly done on Flash these days. Characters are created from simple shapes with movable body parts (mouths, hands etc.) are pasted onto individual layers and animated individually or in concert with the other parts.
The good thing about Flash is that you can position key drawings (important, story-telling character poses of say, a hand) out and the computer will fill in the in-between drawings (all the other drawings between the key drawings to smooth out the movements) automatically. So you can position the hand at one location (a key), and then program the computer to move it to another location (another key) and it will fill in all the in-between drawings by itself (timing is done by the animator). Computers are only good at moving objects around perfectly and stretching/squashing them according to preset rules so you are limited to certain expressions. Of course, complex scenes still need to be animated by hand, but to keep the cost and the time consumed down, animators don't get to do them frequently, if at all.
You can recognize these shows by the extremely smooth movements exhibited by the characters, as well as the bold and uniformed outlines and colors throughout. Backgrounds can be painted by hand, either digitally or on papers( and then scanned into the computer), or created from bodies of static shapes and colors.
Bigger, movie-length animated films use specialized softwares, either developed in-house, or bought commercially like the Toon Boom Animation program. These, however, are almost completely hand-drawn (characters-wise), since you can only create good character animation when you have a feel of the lines and forms of the characters, a thing that is quite difficult to program on a computer.
Some studios use papers and scanners, some use graphic tablets like the Wacoms to imput drawings into their computers. Some parts of a character can be animated while others are put on a different layer and remain static.
You can recognize these films by the slight jittery outlines of the character when he/she/it moves, since each line was drawn to match up with the previous drawings', though never perfectly so, no matter how hard the animators tried. The backgrounds are usually painted by hand (either digitally or manually on papers), or in 3D models that mimic a particular style or both.
Having said all that, yes, most animated shows are still drawn by hand. Some are done on papers and scanners, some are done on computers with Wacom tablets, some combine both in the production process. 2D animation is a craft, and unless computers can draw imaginatively, animators will still have their jobs, drawing them lovingly frame by frame. I hope that helped.
Depending on the budget, deadlines, technology, experience and preference that 2D animations are made one way or another.
Small budgeted shows, destined for the weekly TV slots are mostly done on Flash these days. Characters are created from simple shapes with movable body parts (mouths, hands etc.) are pasted onto individual layers and animated individually or in concert with the other parts.
The good thing about Flash is that you can position key drawings (important, story-telling character poses of say, a hand) out and the computer will fill in the in-between drawings (all the other drawings between the key drawings to smooth out the movements) automatically. So you can position the hand at one location (a key), and then program the computer to move it to another location (another key) and it will fill in all the in-between drawings by itself (timing is done by the animator). Computers are only good at moving objects around perfectly and stretching/squashing them according to preset rules so you are limited to certain expressions. Of course, complex scenes still need to be animated by hand, but to keep the cost and the time consumed down, animators don't get to do them frequently, if at all.
You can recognize these shows by the extremely smooth movements exhibited by the characters, as well as the bold and uniformed outlines and colors throughout. Backgrounds can be painted by hand, either digitally or on papers( and then scanned into the computer), or created from bodies of static shapes and colors.
Bigger, movie-length animated films use specialized softwares, either developed in-house, or bought commercially like the Toon Boom Animation program. These, however, are almost completely hand-drawn (characters-wise), since you can only create good character animation when you have a feel of the lines and forms of the characters, a thing that is quite difficult to program on a computer.
Some studios use papers and scanners, some use graphic tablets like the Wacoms to imput drawings into their computers. Some parts of a character can be animated while others are put on a different layer and remain static.
You can recognize these films by the slight jittery outlines of the character when he/she/it moves, since each line was drawn to match up with the previous drawings', though never perfectly so, no matter how hard the animators tried. The backgrounds are usually painted by hand (either digitally or manually on papers), or in 3D models that mimic a particular style or both.
Having said all that, yes, most animated shows are still drawn by hand. Some are done on papers and scanners, some are done on computers with Wacom tablets, some combine both in the production process. 2D animation is a craft, and unless computers can draw imaginatively, animators will still have their jobs, drawing them lovingly frame by frame. I hope that helped.
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Title Post: What is the difference between a traditional CT Scanner and a Spiral CT Scanner?
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Rating: 100% based on 99998 ratings. 5 user reviews.
Author: Yukie
Thanks For Coming To My Blog
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