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Optics is the science of light, and in photography often refers more specifically to to the properties and construction of lenses or the technical aspects of light sensors.

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4
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3answers
84 views

What determines whether chromatic aberration will be purple/green or red/cyan?

In my experience, both with my own photography and looking online, chromatic aberration is usually purple on one end and green on the other. However, I have also seen the same effect with red and ...
7
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4answers
1k views

Why is my large format lens so much smaller (in length) than my 35mm-format lens?

In general I have found that as the focal length of 35mm (or APS-C) lenses increases, the physical length of the lens increases as well. However, my large format lens is much thinner than other 35mm ...
-1
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1answer
73 views

Can you build a camera obscura indoors, to watch a play upside-down as it's performed? [closed]

I've seen Youtube videos of people who have converted a room into a camera obscura to capture images of skyline/trees/clouds, but couldn't you capture indoor scenes too? Or would you need bright ...
2
votes
1answer
61 views

What are the (dis)advantages of moving the entire lens for focusing vs. only parts of it?

There's a lens adapter available that adapts Leica lenses to Sony mirrorless cameras. It's called TECHART PRO. The key feature is that it allows to use autofocus with the manual lenses. This works by ...
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4answers
89 views

Aperture iris in front of lenses (in object space)

This question discusses the iris placed in camera body and this question does not reveal too much details about external iris. I recall from scattered information that I have read that iris placed in ...
3
votes
1answer
44 views

How is a lens distortion model performed? [duplicate]

So, as the title suggests, how is a lens distortion model (e.g. Brown-Conrady or pinhole camera model) applied on an image? I know it uses some calibration parameters (principal point's coords,focal ...
6
votes
2answers
168 views

How do lenses control “projection”?

How is a fisheye lens made differently from a normal ortholinear projection lens? How are real lenses acting differently from the ideal "thin lens" or pinhole, in terms of how the 3D scene in front ...
5
votes
5answers
243 views

Does sensor size impact the diffraction limit of a lens?

My understanding of diffraction, is that with a small aperture the 'airy disk' (which I understand is the pattern light from a given direction relative to the lens will form on passing through the ...
5
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4answers
637 views

Categorization of 14mm lens as rectilinear?

I used the Panasonic Lumix G Vario 14-42mm f/3.5 -5.6 Asph. / MEGA O.I.S. Lens to take a photo from my balcony. Here's the original RAW (ORF). The symptom I am experiencing is that different ...
21
votes
5answers
1k views

What is the shape of the focal plane?

This is something I just realised I don't entirely know the answer to, so I'm going to ask it here as I think it's interesting. In most non-scientific writing on depth of field, diagrams generally ...
2
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5answers
295 views

Why does it seem like large sensors are necessary for good low-light performance?

Phone manufacturers have recently started advertising the size of the photosites on smartphone camera sensors. They argue that larger photosites lead to better low-light performance. I think a good ...
2
votes
1answer
170 views

Does a lens exist that is parfocal, has a linear zoom throw, and is affordable?

I'm working on a project to create, essentially, a servo-powered zoom lens, using a (D)SLR zoom, a zoom ring gear, and a stepper motor. After mounting the zoom ring gear, I'll attach a pinion gear to ...
2
votes
1answer
138 views

How to obtain 180° FOV and little optical errors?

I'm thinking about building an all-sky camera, i.e. an automated camera that points straight up to the zenith and that captures the entire sky down to the horizon. The idea is to capture celestial ...
6
votes
2answers
184 views

Do nano coatings actually make a difference?

Nikon famously has "nano coatings" on it's higher ended lens, and many photographers online swear that this visibly improves their images. However, it's not clear what the actual improvement is ...
0
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2answers
59 views

Nikon J1, takes pictures but they are all black, doesn't seem to “see” things, lens not the problem

I have a nikon J1, it has always worked well. Today I wanted to take a picture and the screen appeared black, like something was blocking the light completely or I was trying to take a picture of a ...
2
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2answers
126 views

How do universal clip-on iPhone lenses work?

So, recently I see a lot of clip-on Universal iPhone lenses like this (aliexpress link). I have a CCTV camera at home. It has a lens which looks like this from m12lenses.com. Can I clamp these iPhone ...
0
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2answers
87 views

Distortion Removal=Parallax Removal?

So, as the title suggests: does distortion removal caused by lenses means that the parallax is also removed from the pictures?
10
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2answers
192 views

What model does Lightroom use for lens correction?

I use Adobe Lightroom to remove the barrel distortion from GoPro images. Does anyone know if this software uses the Brown-Conrady model to achieve the lens correction? If not which model does it use? ...
1
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4answers
127 views

Does aperture effect the “depth” of faces in a portrait? Wide aperture make noses look shorter, wrinkles less pronounced?

Having a debate with myself that F/10 makes my portraits look better by making faces have less "depth." What I mean is I feel like wider apertures such as f/4 make my nose look longer and wrinkles ...
2
votes
4answers
148 views

How can I fire two cameras simultaneously with different settings but the exact same view?

I have an idea I want to play around with and I was hoping something already exists for it but google has turned up nothing. I want to use two cameras synchronized to fire at the exact same time and ...
1
vote
1answer
93 views

Could someone please give simple explanation of “Principal plane” & “Nodal plane”?

I have read "cardinal point" on Wikipedia for number of times but still I can't get it. My English is not perfect. could someone please explain it in simple English?
1
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1answer
64 views

If a lens has a 4% Barrel Distortion, what does that mean for images?

I know what barrel distortion is, but how do I take a 4% rating and relate that to an image?
2
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3answers
135 views

Light Capture of Full-Frame Lens on Crop Body [duplicate]

Given two lenses: a full-frame lens and a crop lens, both at focal lengths necessary to capture the same frame on their respective systems and at the same f/stop. The physical size of the aperture ...
1
vote
3answers
247 views

What factors make a lens brighter? [duplicate]

Let's say I have two lenses of 50mm, one with maximum aperture f/1.8 and another with f/1.4. I understand that when using maximum aperture, for the latter lens more light will get to the film or ...
22
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2answers
2k views

Why is infrared light's focus point different from that of visible light?

When reading about infrared photography, it's often mentioned that IR's focus point is slightly different from visible light. Why is the focus point of infrared light point different from the focus ...
2
votes
2answers
180 views

What is the “airy disc”, in simple language?

In my understanding, this is relevant to photography because if you are shooting light of a certain wavelength (or primarily so, and such as: a blue scene), your aperture size can affect the sharpness ...
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1answer
90 views

What is the fastest T Stop available?

What is the widest T Stop possible We are having f stops of below even 0.7 NASA lenses What will be the T stop of such lenses with f stop below ONE?
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2answers
208 views

How do I design a secondary lens for my fixed-lens camera to narrow its field of view?

My goal is to put a lens or an array of lenses in front of my actioncam to use its high resolution for recording of undistorted normal-eyed footage, to avoid having to buy two cameras for the ...
1
vote
1answer
158 views

How do wavefronts/wavelets propogate in three dimensions, and why is this important for photography?

The photography book I have talks about waveforms, but it doesn't do a good job of explaining them. So, here's my understanding from the book and google searches (it could be unbelievably wrong.) In ...
4
votes
3answers
585 views

Does focal length change when I adjust the focus? [duplicate]

When I adjust the focus of my camera, in general, does this affect the focal length? I have heard that it does.
4
votes
1answer
175 views

Can a teleconverter make lenses designed for a “crop” sensor cover full frame?

I have a crop lens. Can I fill a full-frame sensor adding an appropriate tele converter (focal length extender? Specifically, I have a 1/2" C-mount lens and terrible vignetting on a full frame camera. ...
3
votes
1answer
160 views

Is it possible to make your own focus distance scale?

I'm using a Nikkor 18-105mm kit lens and it doesn't have a distance scale on its focus ring, is it possible to create your own distance scale by knowing the 0 and the infinity focusing points on the ...
3
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1answer
292 views

What could cause this visible artifact which seems to a be a glowing inverse of something outside of the frame overlayed on this photograph?

An acquaintance recently posted an image to FB from his recent trip to the JFK Historic Site asking for an explanation of a visible artifact he states was not visible to the naked eye but was visible ...
0
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1answer
46 views

Recommended F-Stop for older Canon 35mm F/2 [duplicate]

I have a few year old Canon 35mm F/2 lens (Here it is on Amazon). I've been shooting wide-open, but I realize that doesn't make for the sharpest photos. What would you say would get me the sharpest ...
1
vote
1answer
124 views

Is the Panasonic Leica Summilux the same quality as a non-Panasonic Leica summilux?

Is there an advantage to having a Leica Leica lens vs. a Panasonic Leica lens? To my ability to examine them, they look like the same on the inside. Would this be correct? The Leica Leicas are ...
0
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3answers
202 views

Why don't we have a single lens e.g. say a 18-200 f/1.2 lens for the SLR camera? [duplicate]

Right now we have multiple interchangeable lenses. So why don't we have a single lens, say a 18-200 f/1.2 lens? Are camera manufacturers deliberately avoiding that or it is that it is physically ...
11
votes
3answers
880 views

Why are superzoom lenses small but giant telephoto lenses huge?

This week I've read two news stories about two different camera lenses that can magnify things that are very far away. The first is the Nikon Coolpix P900, which is a point-and-shoot camera that ...
1
vote
4answers
196 views

What lens designs are sharper than a pinhole lens but also allow for multi-month exposures?

I have a homemade pinhole camera (film) that I use for taking super long exposures (multiple months). And while the results are fun, I would like to improve the sharpness of the image. Is diffraction ...
0
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2answers
498 views

Is there a formula to calculate the physical size of an image?

I'm trying to figure out the size of the physical space an image represents (IE, how many meters long/wide the real world in the image is), but I can't seem to find a formula that works with only the ...
0
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2answers
388 views

What causes barrel distortion?

Here are some scenarios for barrel distortion: When a target is too close to a camera, the photo will show barrel distortion. My flip cell phone's camera often produces barrel distortion. Some ...
1
vote
1answer
69 views

Why can a lens still function when subject to severe physical degradation?

Consider the following two modifications to a camera lens: Obstructing the about 75% of the lens's front element with an opaque filter as shown here: https://www.youtube.com/watch?v=43W159gPpdQ. ...
0
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3answers
598 views

Equivalent focal length and aperture of 150mm medium format lens on a 35mm camera

I'm mounting a Hasselblad Sonnar C 150 mm f4 on a 35mm sensor (43mm diagonal) camera. What is the calculation to get the new angle of view and equivalent focal length? Does this also affect the ...
1
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4answers
217 views

How can I compare different lenses in terms of quality?

I am currently looking to buy a new lens to replace with kit lens, having an extra reach, faster, better image quality and also better video quality. Without buying all the lenses I have shortlisted, ...
2
votes
3answers
265 views

Is a quartz lens necessary to prevent UV blocking on full spectrum enabled cameras?

I have read that in order to operate a "full spectrum" camera properly, so as to not block light in the ultraviolet portion of the spectrum, that one needs to acquire quartz lenses for one's camera. ...
0
votes
1answer
129 views

Projector Design and lenses

I am working on a project where I need to project a single image onto an object, Originally I was looking at the digital projector route but due to cost and complexity this has been ruled out. I found ...
5
votes
1answer
162 views

Background warping through foreground defocus

I came across this effect the other day, and have spent the better part of the last week trying to figure out exactly what is happening. When photographing two layers, with the foreground in front of ...
0
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2answers
159 views

Why does the same f-number mean same amount of light? [duplicate]

Intuition tells me that a bigger lens will collect more light with the same f-number than a small lens. But photographers tell me I am wrong. I cannot understand why. There are quite a few posts both ...
2
votes
2answers
221 views

What is the importance of the back focal length of a lens?

What is the effect and importance of the back focal length of a lens? For instance, if I look at these two lenses by Ricoh, they have the same focal length and aperture, but their back focal lengths ...
0
votes
1answer
141 views

Lenses round ..Photographs square shaped why? [duplicate]

If camera lenses are round then why is the photograph taken by the camera is square-shaped? photography
14
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4answers
5k views

How can a super tiny iPhone 6 Plus lens produce significant DOF?

According to Apple specs the iPhone 6 Plus thickness is 0.28 inch (7.1 mm) and the lens length is only a part of that. And according to an article I found, Depth of Field is a function of "aperture ...