Skip to main content

Camera Lens Aperture Overview

Here is another learning series article and video. This time I go over the camera lens aperture.




The camera lens aperture is the variable opening inside the lens that lets more or less light into the camera. A small aperture has a larger number.

See a full technical description of aperture on Wikipedia:

http://en.wikipedia.org/wiki/Aperture

Also important is the f-number that explains what the aperture number means:
http://en.wikipedia.org/wiki/F-number

f-number = focal length / diameter of the entrance pupil

So if we want to know the entrance pupil size of an 100mm f4 lens we calculate it like this:
Diameter = 100 / 4
Giving us a 25mm front lens element.

An 85mm f1.4 lens results in a 60.7mm front lens element (85 / 1.4 = 60.7143).


Aperture size vs. depth of field.

The most important statement I didn’t cover in the video is “the aperture determines how collimated the admitted rays are,” so a small aperture has very collimated rays of light getting through to the camera’s sensor.

A large aperture (f1.4) will give you less depth of field (distance of perceived sharpness), and a smaller aperture (f22) will give you a larger depth of field.


Labels:

Popular posts from this blog

Nikon Z5ii Announced and My Thoughts vs the Original Z5

The Nikon Z5ii was announced recently. I haven't actually used this new camera myself, so keep that in mind. This is going to be mostly me looking at the specs and comparing it to the original Nikon Z5, which I've been using for a few years now. Check out the full video on YouTube:   The original Nikon Z5 camera. Overall, the original Z5 isn't a bad camera. I've gotten it to a point where it works how I want it to and it's reliable for what I do.  My main use case is often anime and comic conventions, going there and taking photos of people in cosplay. I usually use the 40mm f/2 lens on the Z5, and it works well for that.  First-person view using the Nikon Z5 at an anime convention. Nikon Z5ii vs Z5: The Spec Sheet Comparison  Nikon has a handy comparison section on their Z5ii page, so let's break down some key differences based on that and my experience with the original. Nikon's website comparing the Z5ii and the original Z5 specifications. First up, the ...
Read more

EF-M Sigma 56mm vs. Viltrox 56mm

I was curious how the two native Canon EF-M 56mm f/1.4 lenses compared. Is one better in image quality or features than the other? At least right now there is a significant price difference between the two. Check out the embedded video to see how it goes!  Sigma and Viltrox 56mm lenses Check out the YouTube video here : Sigma 56mm f/1.4 DC DN Contemporary Lens for Canon EF-M: B&H: https://bhpho.to/3bNQUjk Amazon: https://amzn.to/3cC8pUb ebay: http://ebay.us/5Q3NxW Used on KEH: https://shrsl.com/2b947 Viltrox 56mm f/1.4 AF lens for Canon EF-M: Amazon: https://amzn.to/39sl5Pa B&H: https://bhpho.to/3nXMoF0 ebay: http://ebay.us/b4IRWE As an affiliate of these shops, I earn from qualifying purchases!  Here are the notes I wrote up while compiling data and deciding what I should mention in the video. Physical properties of the lens: The Sigma lens is shorter but thicker than the Viltrox.   Weight is 280g for the Sigma and 290g for the Viltrox. Sigma: 66.5mm x 59.5m...
Read more

Brightin Star 60mm f/2.8 2:1 Macro Lens Overview

In this article, I'm going to go over my experience using the Brightin Star 60mm f/2.8 2:1 macro lens. Brightin Star sent me this lens based on my collaboration terms . They had no say in the article or videos I've produced and have not previewed anything before publishing it.  The full video I produced about the lens: Build Quality The lens in hand. The Brightin Star 60mm f/2.8 lens feels solid. It features an all-metal casing, including a metal mount, which gives it a weighty feel in hand. This is a completely manual lens, meaning the aperture and focus are both mechanical. You won't get any electronic data transferred to your camera, which is generally fine for macro lenses since you'll typically be using manual focus anyway. However, not having any EXIF for aperture settings saved in the camera is something to consider.  The metal mount with no electrical contacts. The aperture ring is smooth with no clicks, which is useful for video situations. But for photography,...
Read more