Questions tagged [calculations]
Photographic math — equations, formulas, algorithms related to making or processing images.
166
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How to calculate average gamma from gray scale?
I need to calculate average gamma from 9-step grayscale.
I have a grayscale measurement export from HCFR.
I can calculate gamma for every gray step like this:
Row A is the grayscale measurement ...
- 141
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1
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55
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Calculating FOV for mismatched lens/sensor size
I have this 50mm lens that gives the FOV for a 2/3" sensor in its spec sheet:
Diagonal: 12.6°
Horizontal: 10.1°
Vertical: 7.6°
I have this camera, which, according to its spec sheet, has a 1/2....
- 587
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2
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Calculate the coordinates for secondaries on CIE chromacity diagram?
I'm trying to use this solution to calculate the secondary coordinates from primaries: https://photo.stackexchange.com/a/75238/115749
But it won't work for any other primary than those in the solution ...
- 141
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How can I measure the flicker frequency of a light source with my phone?
I have a Hue light and want to measure the flicker frequency (due to the PWM) without buying an expensive photometer. Is it possible, to calculate it with such an Image, by counting the bars from the ...
- 155
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How do I determine distance to an object when I know the object's size and the camera's angle of view?
I'm trying to find the distance of an object, where the original size of the object is known. Unfortunately, I cannot seem to find either focal length or sensor size online, but I know that the camera ...
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49
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DOF formula vs the simplified DOF formula
I was calculating the theoretical difference in the change of the DOF (depth of field), between a frame achieved on a 25mm signature prime and an "identical frame" achieved by using a 75mm ...
- 343
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Calculating the size of an object from a single image, given the distance from the camera
I was looking at other questions on here and I'm pretty sure it's not a duplicate so here it goes. I'm working on a problem where I need to calculate the size of a particular object in an image. The ...
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140
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How does an afocal lens produce an image on a screen?
I'm really confused about it. If such a lens is necessarily focused at infinity and does not have a plan of focus, then, does it mean it can produce a clear picture on a screen, no matter how close it ...
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How to count the amount of pixels an object in a photograph takes up
I have been trying to find out the distance of an of object from an image using this calculator https://www.scantips.com/lights/subjectdistance.html
But I need to know how many pixels long the object ...
- 103
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Step-by-step description of the preparations, gear, apps, settings, ... needed to take image of a plane before the moon
I recently saw the following photograph on Facebook by ePixel Aerospace:
with the following caption:
Mission accomplished!
Just about a year ago, I was commissioned to
capture a special Qantas/Lunar ...
- 703
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877
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How to calculate the Aperture and Focal length needed for depth of field
I have a virtual camera in a game engine.
The camera has an DOF setting where you can set the :
Distance to object
Aperture
Focal length
I would like to set a depth of field (lets say about 5m) ...
- 11
2
votes
3
answers
595
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How to determine via a math formula when a lens is wide angle or macro
Lets say I have a device with 3 separate lenses. One will be the main reference lens, and then the two others may be a wide angle lens or a macro lens, or also even a replica of the main reference ...
- 121
3
votes
1
answer
611
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Is x50 zoom camera able to zoom 500 meter target area from a 6 km distance?
I have a x50 zoom camera and here is some specs of the camera and lens:
Focal length: 6 mm ~ 300 mm
Field of view: 58.4° ~ 1.4°
Resolution: 2 MP
I drew a scheme to explain my question properly, you ...
- 133
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624
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How to calculate height of camera and ground coverage via geometry?
I have a GoPro7 that I will mount on a pickup vehicle to capture ground images with video capture.
The camera isn't top down but has about 20 (or 30) degrees inclination from the vertical axis.
I want ...
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How to calculate under or over exposure using these values TTL meter (Lux), Shutter speed and ISO/ASA
I would like to get into film photography as a hobby, I own two 35mm film Cameras which both have broken TTL meters, they are common Fujica bodies and I would like to replace the (battery damaged) TTL ...
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