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3MiB, 3450x2200, Lenses_with_different_apertures.jpg

Anonymous Sat 15 May 2021 02:35:08 No.3882248 View View Reply Original Report

Quoted By: >>3882255 >>3882262 >>3882270 >>3882280 >>3882335

Sorry of this is a stupid question but I'm new. I just got a Nikon D5300 that comes with the 18-55 NIKKOR lens. I'm just pretty curious how the aperture setting works.

I recognize that in the lens itself is a physical aperture that changes as I rotate the zoom lens barrel. This makes sense to me. However the camera itself allows me to seemingly digitally change the aperture, especially in Aperture-Priority mode. How does this work? When I modify this setting (between f/4.5 and up to f/29), the physical aperture in the lens doesn't change, so I don't understand where this change is coming from.

Is there another mechanical aperture inside the DSLR body itself that I'm not seeing? Is this some kind of digital aperture that the CCD has built on?

Anonymous

Anonymous Sat 15 May 2021 03:17:08 No.3882255 Report

Quoted By: >>3882272

>>3882248
There are a few things at work here:
1. The aperture changing as you zoom is a result of variable maximum aperture, essentially the aperture isn’t changing but the effective aperture is as a result of it moving or not within the lens

2. The lens will always stay wide open until you take a photo, set it f22 and 1 sec exposure and look at the front of the lens to observe it stop down and open again , th camera body does this with a little mechanic lever

Anonymous

Anonymous Sat 15 May 2021 03:22:36 No.3882262 Report

Quoted By: >>3882265

>>3882248
pro-tip:
People use the word "Fast" to describe how wide open the aperature can get. an f1.0 is 'faster' than an f1.2 because the opening is larger. (i'm over-simplifying it)

but its not how fast your camera goes if you throw it off a cliff. all cameras fall at the same rate of 9.8 N/kg

Anonymous

Anonymous Sat 15 May 2021 03:25:23 No.3882265 Report

Quoted By:

>>3882262
>but its not how fast your camera goes if you throw it off a cliff. all cameras fall at the same rate of 9.8 N/kg
That’s false

Anonymous

Anonymous Sat 15 May 2021 03:38:30 No.3882270 Report

Quoted By:

>>3882248
>Is there another mechanical aperture inside the DSLR body itself that I'm not seeing?
Nope; aperture's in the lens on (almost) every camera system, and that includes the Nikon F system that your D5300 is a part of.

Aperture is related to focal length, but not in the way it sounds like you're understanding it. Quick intro: The aperture (or f/stop) setting represents the ratio of the lens' focal length to its physical aperture size, because that ratio is what determines how much light is hitting the sensor. So a hypothetical 100mm lens with a 50mm aperture is going to be f/2.0 (focal length of 100mm divided by 50mm equals 2.0), and a hypothetical 200mm lens with a 100mm aperture is also going to be f/2.0, and those will both let the same amount of light hit your sensor despite the 200mm f/2.0 being a physically larger aperture.

It's actually a little more complicated than this in practice because that only holds true for a theoretical basic lens system and modern camera lenses are actually complex systems with a lot of different elements and moving parts, especially zooms. But you don't actually need to know any of that because the lens and the camera hide all that complexity from you, so you just need to know that your specific 18-55mm lens has an f/3.5 maximum aperture at the 18mm end but only an f/5.6 maximum aperture at the 55mm end. This means that if your camera wants to have your aperture as wide as possible, that aperture number will change when you zoom.

Conversely, if you change your aperture to something f/5.6 or smaller (which is to say, smaller aperture, but larger f/number), it'll stay where it is when you zoom.

So, the aperture value you're setting with the control dial in aperture-priority mode is actually the aperture setting. It only changes when you zoom because because sometimes that setting isn't actually an option with the lens' zoom position, so it has to change it for you.

Anonymous

Anonymous Sat 15 May 2021 03:41:44 No.3882272 Report

Quoted By: >>3882274 >>3882334

>>3882255
>the camera body does this with a little mechanic lever
This is true with most Nikon lenses, and I think it's true with the specific 18-55 that the op has, but it's not true with the latest Nikon lenses. They recently switched to an electronic aperture control like most other companies use, thus divesting themselves of the last mechanical, non-electronic control connection between camera body and lens that was a holdover from the original F mount, just in time for F to get basically abandoned for the new Z mount.

Anonymous

Anonymous Sat 15 May 2021 03:44:06 No.3882274 Report

Quoted By: >>3882334

>>3882272
I know, which fucking sucks for backward compatibility to my F5 :( third party are catching up to electronic diaphragm as well

giannis

giannis Sat 15 May 2021 03:55:28 No.3882280 Report

Quoted By:

>>3882248
>How does this work? When I modify this setting (between f/4.5 and up to f/29), the physical aperture in the lens doesn't change
It does change, momentarily, when taking the photo.
The fact that it remains wide open at all other times (before taking the photo, after taking the photo) is because if it was stopped down, the viewfinder would be very dark and it would be hard to focus.
This kind of operation, called "automatic aperture", was a huge convenience feature when it got introduced over 60 years ago and very quickly all manufacturers adopted it.

Anonymous

View Same Google ImgOps iqdb SauceNAO apu7.png, 63KiB, 750x451

Anonymous Sat 15 May 2021 06:48:20 No.3882334 Report

Quoted By: >>3882336 >>3882337

>>3882272
>>3882274
What's the advantage of an electronic aperture over the traditional mechanical setup? It lets you control the aperture from within the camera, but do people really prefer that? I'd much rather move a physical ring with numbers printed on it than a tiny plastic wheel with the only feedback on-screen. Ironically Nikon are moving away from mechanical aperture while others like Fuji and Sony are putting aperture rings back on their lenses, albeit in electronic form.

Anonymous

Anonymous Sat 15 May 2021 07:06:57 No.3882335 Report

Quoted By:

>>3882248
Congrats anon, you picked what's arguably the most ergonomic camera ever made. I used to have a D5100 myself, amazing piece.
The aperture changing as you change the zoom has to do with the zoom not being a constant aperture design. It has to do with the maximum aperture at a given length. The one you're "changing digitally" is the aperture for when the picture is going to be taken. The camera measures light and focuses wide open, then it stops down as other anons already explained.
The D5xxx and D3xxx series (and shamefully the D7500, crippled to make the D500 more attractive) have a noticeable flaw: the lack of a depth of field preview button. Such a button stops down (closes the diaphragm to an aperture smaller than maximum) as you compose. However, if you want to preview the DoF you can use live view, though.
The creative use of aperture is essentially adjusting the depth of field.
It is said that larger apertures are "faster" because they allow you to use higher shutter speeds or lower ISO sensitivity while achieving an equivalent EV (exposure value).

Anonymous

Anonymous Sat 15 May 2021 07:19:12 No.3882336 Report

Quoted By:

>>3882334
The only benefit is planned obsolescence, they’ll claim it’s for more accurate aperture control but that hasn’t been a real problem for 100’s of years. As it is with existing cameras you can already control the aperture via the body or aperture ring

It’s just more complicated yet cheap electronics that will eventually fail prematurely

Anonymous

Anonymous Sat 15 May 2021 07:21:59 No.3882337 Report

Quoted By:

>>3882334
Faster aperture function for high FPS if I recall correctly.
Related to sports and AF.

Anonymous

View Same Google ImgOps iqdb SauceNAO s-l16000.jpg, 97KiB, 1001x1001

Anonymous Sat 15 May 2021 09:01:45 No.3882366 Report

Quoted By: >>3882368

When shooting a DSLR with ancient screw-mount lenses, you actually have to operate the aperture by yourself. The lenses have a lever or switch with two positions; "A" (aperture stays wide open, useful for focusing) and "M" (aperture stops down to selected setting). So you'd first have to focus in the A position, then select your aperture, then meter and shoot in the M position. It's just as inconvenient as it sounds.

Anonymous

Anonymous Sat 15 May 2021 09:03:49 No.3882368 Report

Quoted By:

>>3882366
Please elaborate on what this has to do with a modern Nikon F mount DSLR?

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