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I calculated some values for a lens with a focal length of 25 mm. To focus to infinity, the sensor should be 25 mm away from the reference plane of the lens. A mounting error of + 0.001 mm shifts the infinity point to 625 m. An error of 0.01 mm to 62.5 m, 0.1 mm to 6.27 m and 1 mm to only 0.65 m. An error of + 0.5 mm shifts the infinity point to 1,27 m. I ...


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Your question is about DIY but you are not a DIY person. Perhaps you need to hire someone to do the work for you? Replacing the light switch to a dimmer is not hard, but depending on local laws it can be illegal for you to do it yourself. If it is legal then it usually requires some basic electric knowledge, a flat and a star head screwdriver and 10 ...


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Some light fixtures can adjust light level using a gauge, but I'm renting and the utilities are beyond my control. There are many options for smart lights these days (Philips Hue for example) which offer levels of dimming via an app on your phone. my idea was to simulate a shoot-through umbrella by taping white printer paper over the lights (they are ...


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If an ideal simple lens with focal length f is pointed at a subject at distance s, it will produce a focused image at distance 1/(1/f-1/s). For a subject at infinity, 1/s will be zero, so the distance will be 1/(1/f), i.e. distance f. For a subject which is at distance 2f, 1/s will be 1/2f, so the distance will be 1/(1/f-1/2f), i.e. 1/(1/2f), or 2f. ...


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If I have built my device with the correct distance between the flange and the optical plane, does this mean the (inexpensive) lens I am using is bad? If you had built your device using the proper specified flange distance of 17.526mm instead of rounding it off to 18mm you probably would not be asking this question. 0.474mm doesn't seem like much, but it ...


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Potentially. It could also be that your measurements are slightly off. To find the perfect distance, you can focus on infinity, and then slowly move the lens nearer, until the picture is sharp. That is the correct distance; however, you should give it an extra tenth of a millimeter or two, to avoid issues with temperature changes or slight movement when ...


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If not, do I move the lens away or closer to the optical plane to fix the problem? If the lens will focus on near subjects, but not on a subject at "infinity," then that means that the lens is too far from the sensor. You need to move it closer.


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