Slains Castle

by pakman

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We desire a faithful image. We image a rectangle with the same aspect ratio as our camera’s senor/film frame. If we image at unity (life-size) we expect the image of the rectangle to kiss-off at the corners of the image area. With barrel distortion the image will under spill. With pincushion distortion, the image will over spill. The delta  (valuable ...


The only real and major difference is the amount of light that is let in. Larger front element is going to let in so much more light. I dont know why people never talk about this or know about this. Think about it like fixed focal length lenses. Put a 35 mm lens on your camera and get the exposure correct. Now dont change those setting and put on a 50mm or ...


In the case you have things lying around, you can go this route: However, I agree, that it might come in more handy (and most likely cheaper and with better image quality) to use a smartphone or some other camera.


zone plat is a special screen to block off light from every half period zone. in zone plat amplitude A=A1-A2+A3-A4+A5-A6.+..+(-1)m-1Am . THE EFFECT IS the removal of either all negative or positive term in amplitude.


FF sensors behave better in low light situations because of the pixel pitch, and inherent physical size of the photo sites. It does not have to do with the size of the image circle being created by the lens. If an aps-c sensor and a full frame sensor are the same MP, then the area of the image circle we can capture increases, causing the density of the ...


The job of the camera lens is to project an image of the outside world onto the surface of the image sensor. All lenses project a fairly large circular image. Only the center portion has good definition. The boundaries of this image are indistinct and dim. The boundaries are blurred because the image forming rays hit obliquely. What should image as points ...


Your last sentence gets it right. The extra light is wasted because it falls outside the sensor area. In the approximation that your lens is a single thin lens (it is not, but it is a useful way to think about it) the rays that pass through the center of the lens are not changed in direction. In full frame, you need rays that pass at a wider angle so you ...

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