Fresh Dew on a Rose

by adarsha joisa

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The focal length of a lens only applies to objects at infinity, and is the distance (𝑓 in the diagram below) between the lens and the sensor when such an object is in focus. The focal point (F) would actually be ON the sensor. (image cropped from Wikipedia page) As an object gets closer to the sensor, the focal point moves away from the lens, meaning the ...


I think I get what you are asking - we can assume the sensor limits resolution, and if we know magnification of the system we can then relate this to an object space resolution limit. Your approach is going in the right direction, but you should use the rayleigh criterion as the definition of resolution on the sensor (this assumes diffraction limit. ...


What you did looks correct, you are using a form of h=f*tan(theta) which is used a lot in optical design. Usually one would use half the vertical sensor size (7.02/2 = 3.51) and half the height of the object(91/2 = 45.5), but in this case it doesn't matter. It is important to note that this equation assumes some things, mostly that the axis of the lens is ...


Yes, the problem is that lenses distort the image from the simple parallel projection you would need to keep the math that simple. Fortunately, the math and data to correct lens distortions are readily available. Some post-processing software can identify the lens and its settings from the image metadata and, using lens reference data, apply corrections to ...


It seems that you are looking for the resolution of a given optical system. If this is true then such estimation is rather complex as it involves both the resolution of the lens and the resolution of the sensor. These computations take into account basically the lens quality and the apperture, the size and density of the sensor and more. In addition, to be ...

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