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### How can the height of a subject in picture be calculated? [duplicate]

Maybe is not the perfect stackexchange site to ask this but I try. Feel free to move or close my question, but, if you can, suggest me where I can ask this one: I took a photo with a compact digital ...
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### Estimate object size [duplicate]

If I have a [digital] photograph of an object, can I estimate it's approximate size? I notice with interest that my camera (Nikon D3300) seems to record the approximate focal length of the lens in ...
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### How do I use EXIF tags to determine the length of an object in focus? [duplicate]

I have an image with EXIF information encoded into it. What I need to know is what information I can use to determine the length of a certain object. For example, are there tags that hold the camera ...
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### How do I calculate the distance of an object in a photo?

If I took a picture of a windmill on the horizon — given that I know the sensor size and the focal length of the lens and other factors to do with the shot — could I calculate how far away an object ...
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### Calculate object size when I have physical pixel size

How do I calculate the object size when I have focal length = 25 mm distance to object = 700 mm CCDs pixel size = 4.4 µm ? My camera is this USB 1/1.8" CCD C-mount camera. Edit: Could this work?...
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### What kind of lens is used in this picture of Earth?

The photos in an answer to this question show the Earth as very small as seen from the moon. I suspect that the lens used doesn't reflect how our eyes would see the Earth from the moon. Is there a way ...
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### Calculation for getting dimension of object in image not working

I am trying to calculate the dimensions of an object in an image. This is a sample image I took to get height of blue shirt: I am following the math from this page with sastanin's answer to How do I ...
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### How to automatically measure subject dimensions (width/height/distance) without physically measuring?

What methods are used for automatically measuring the dimensions (width/height/distance/etc.) of a subject without having to get in there with a measuring tape? I am just starting to get into ...
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### Camera image in pixel to real image in meters size relation [closed]

first post so please be nice. I am doing an image processing project and my problem is now that I would like to know how big my digital image is in the real world. I have: digital image: 336x256 ...
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### How to calculate digital photo precision based on camera specification?

I'm doing a project which involves analyzing an object's width from a photo with given precision of about 0.1 mm. I am to the point where I have to choose which camera to buy in order to obtain the ...
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### How to determine film size from smartphone image exif data?

I took an image from my phone and got its exif data below. It was a samsung note 4, which uses a 35mm film size (24x36) with a 43.27 diagonal. But what I am trying to figure out is the sensor diagonal ...
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I am trying measure real object height from an image. I'm using the below formula  \text{real height [mm]} = \frac{\text{object height [px]}\times \text{pixel size }\left[\mathrm{mm\over px}\right]\...