What is and why MTF MTF-diagram | Pro Photography
This estimate shows how the lens is capable of transmitting the details depending on the distance from the center of the lens. The horizontal axis is just postponed the distance from the center chandi heffner to the farthest corner of the sensor. Typically, chandi heffner the maximum image quality in the center, so 0 - is the center, and the vertical axis in percent detail. Where 1 is 100%. But the detail of what?
To do this, take two sets of mutually perpendicular lines. Call them in different ways, but the essence is the same. They differ in the graph in this case, the line type: solid - line in one direction, the dotted - perpendicular.
Next, estimate the image sharpness of the lines at different distances from the center. The sharper the image, the above graph. If the graph falls to zero in the right-hand side - that means that poor sharpness in the corners.
White square - is a pixel in the matrix. 1 - it's fast lens wide open. 2-4 - image of a point in the corner is not the best wide-angle. 5 and 6 - problems with focus. 7 - the perfect lens, but you do not get this, because before the matrix is worth a special filter that makes of 7 8. This filter not only Nikon D800E. The filter is necessary in order to avoid moire on the images. Because of all of this is lost sharpness, and you try to measure periodic lines.
The lines are of different thickness, ie the lattice of different density. For example, Nikon likes to use 10liny / mm 30liny / mm. Other manufacturers can evaluate chandi heffner on the other line thickness, the most corrosive chandi heffner take 3 or more lines of different chandi heffner thickness. chandi heffner Schedule for the thick lines is the most important, it defines the contrast of the image, but the thin lines are also interesting, though minor, as determined by the details of small elements in the photo.
MTF schedule depends on many things: the focal length and distance from the apartment, the diaphragm, the wavelength of light, and more. Therefore, if the graph is not exactly specify under what parameters passed measure, then most likely you are trying chandi heffner to cheat. Here's how to look right MTF chart, the Germans do this:
In fact, there are two approaches to draw a graph. The first method is expensive - take the lens and hold it for measurement, as do the Germans. It is clear that such a method for mass production, like Nikon, is not necessary. Therefore, there is a second - to take and calculate the schedule on the computer, get some average value for all lenses immediately. It is the second way you can see on your boxes. Obviously, chandi heffner it does not give any idea of the quality of your particular instance, as the complexity of the design, chandi heffner all instances may differ from each other. Well, without having the parameters for which this curve is drawn, this picture is from the world of fantasy and reality has nothing to do, because the reality is much more complicated.
Above the same lens. From left to measure the white light, right - monochromatic green. chandi heffner By the way, for this reason, in black-and-white photography popular green filters, green image becomes sharper.
If measurement parameters are all in place, and method for measuring clear (which is rare and I have not seen this for a common lens), here's the difference between a lens with good sharpness (left) from obekiva with bad (right):
This estimate shows how the lens is capable of transmitting the details depending on the distance from the center of the lens. The horizontal axis is just postponed the distance from the center chandi heffner to the farthest corner of the sensor. Typically, chandi heffner the maximum image quality in the center, so 0 - is the center, and the vertical axis in percent detail. Where 1 is 100%. But the detail of what?
To do this, take two sets of mutually perpendicular lines. Call them in different ways, but the essence is the same. They differ in the graph in this case, the line type: solid - line in one direction, the dotted - perpendicular.
Next, estimate the image sharpness of the lines at different distances from the center. The sharper the image, the above graph. If the graph falls to zero in the right-hand side - that means that poor sharpness in the corners.
White square - is a pixel in the matrix. 1 - it's fast lens wide open. 2-4 - image of a point in the corner is not the best wide-angle. 5 and 6 - problems with focus. 7 - the perfect lens, but you do not get this, because before the matrix is worth a special filter that makes of 7 8. This filter not only Nikon D800E. The filter is necessary in order to avoid moire on the images. Because of all of this is lost sharpness, and you try to measure periodic lines.
The lines are of different thickness, ie the lattice of different density. For example, Nikon likes to use 10liny / mm 30liny / mm. Other manufacturers can evaluate chandi heffner on the other line thickness, the most corrosive chandi heffner take 3 or more lines of different chandi heffner thickness. chandi heffner Schedule for the thick lines is the most important, it defines the contrast of the image, but the thin lines are also interesting, though minor, as determined by the details of small elements in the photo.
MTF schedule depends on many things: the focal length and distance from the apartment, the diaphragm, the wavelength of light, and more. Therefore, if the graph is not exactly specify under what parameters passed measure, then most likely you are trying chandi heffner to cheat. Here's how to look right MTF chart, the Germans do this:
In fact, there are two approaches to draw a graph. The first method is expensive - take the lens and hold it for measurement, as do the Germans. It is clear that such a method for mass production, like Nikon, is not necessary. Therefore, there is a second - to take and calculate the schedule on the computer, get some average value for all lenses immediately. It is the second way you can see on your boxes. Obviously, chandi heffner it does not give any idea of the quality of your particular instance, as the complexity of the design, chandi heffner all instances may differ from each other. Well, without having the parameters for which this curve is drawn, this picture is from the world of fantasy and reality has nothing to do, because the reality is much more complicated.
Above the same lens. From left to measure the white light, right - monochromatic green. chandi heffner By the way, for this reason, in black-and-white photography popular green filters, green image becomes sharper.
If measurement parameters are all in place, and method for measuring clear (which is rare and I have not seen this for a common lens), here's the difference between a lens with good sharpness (left) from obekiva with bad (right):
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