Westminster fountain at sunset

by Jorge Córdoba

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0
votes
3answers
72 views

Do I use the crop factor in calculating aperture size and area?

How do I calculate the aperture size and area, considering an 35mm equivalent focal length value and non-equivalent aperture f-number (in terms of exposure, no multiplication of the crop factor of the ...
0
votes
1answer
100 views

Where can I find tables of common shutter speed and aperture values? [duplicate]

I'm working on image processing software (mind that I'm a programmer and when talking about photography, I'm "tabula almost rasa"). In this software, I'm using a RAW decoder that returns a data ...
4
votes
1answer
205 views

How to calculate the optimal pinhole size?

As far as I've understood, optimal diameter for pinhole size is calculated by formula where d - the optimal diameter for pinhole c - constant f - focal length (distance between pinhole and ...
0
votes
3answers
233 views

Can I estimate the light gathering power of a lens by measuring size of entrance pupil?

Supposing I have an unknown lens of which I don't know f/# and focal length. I want to estimate the total amount of light that my lens can collect which, I believe, is given by the solid angle that my ...
3
votes
1answer
107 views

Lens f-number and speed on adapted lenses

A lens has a focal length, and its entrance pupil has a diameter. The ratio of these is an f-number. The size of the entrance pupil is limited by the size of the front element, and we describe lenses ...
0
votes
5answers
2k views

is the Nikon 35mm f/1.8 worth it after i have the kit lenses? [duplicate]

I have a Nikon DX (D5100) camera with the two most basic kit lenses: 18-55mm f/3.5-5.6 VR and 55-200mm f/4-5.6 VR. These two lenses cover lots of scenarios, but I'm starting to believe there is more ...
0
votes
3answers
504 views

What is the diameter of the lens' aperture in mm terms?

I'm planning to create a customized aperture effect. Like this one in the Photo. I'll be doing a DIY customized aperture that will be attached to the filter. My lens' widest aperture is F/1.8 ...
1
vote
3answers
375 views

Is it possible to calculate focal length if you know the aperture?

I need focal length (for my IA homework), but I didn't know that in real world I would only get the aperture. Ok, my camera is an Olympus X-21, and manual says: -----Olympus lens: 6.3 to 18.9 mm, ...
2
votes
2answers
400 views

Why are the area of aperture, focal length, and amount of light specified in these terms?

So I'm looking at the wikipedia article on Aperture, and I'm a bit confused. I understand aperture to be the diameter of the hole that lets light in. In the article, someone states that The ...