Questions tagged [distortion]

a lens defect which causes straight lines to be curved or bowed

Filter by
Sorted by
Tagged with
1
vote
2answers
62 views

How to transform a picture with reference points on another picture?

I don't exactly know how to describe the problem. I have two maps that partly show the same extent of a place, but on the whole, the scale, rotation and protection might be different. I still want to ...
8
votes
2answers
1k views

How does camera firmware obtain lens distortion correction parameters?

I use an Olympus MFT system and one thing I notice is that for most Zuiko MFT lenses there is significant barrel distortion as seen in the raw images. However, if you look at the jpg's, often they ...
5
votes
4answers
120 views

Why are flatbed-scanned images warped when compared to itself scanned & rotated 90 degrees?

This has been absolutely baffling me. I scanned an image both vertically and horizontally on the flatbed of my HP Color LaserJet Pro MFP M277dw using Windows Fax and Scan. I then used Gimp to rotate ...
4
votes
3answers
1k views

Why do drones capture images that are curved at edges?

Every photos I have seen of drones taking images at high altitudes, had a kind of curvature at the edges of the photograph. I mean, I know the earth is round. But it is also huge, and IMO, you shouldn'...
0
votes
1answer
145 views

Why is the person in the corner of this photo distorted? [closed]

Is it just me, or does the guy in the bottom left look really weird? What is causing the distortion? Anti-UK protesters outside the British embassy in Tehran on January 12, 2020. Atta Kenare/AFP/...
-1
votes
3answers
76 views

Is crop and longer focal length equivalence not valid with rectilinear ultrawides?

The common assumption is that a crop will equal a longer focal length in perspective. However, rectilinear ultrawides will very visibly distort faces and spherical/cylindrical objects that are well ...
0
votes
3answers
211 views

How to find out what part of image is less lens-distorted?

I'm developing an application which uses a Canon DSLR to sequentially shoot an object from different views. Often the object is too big to fit in frame so I have to make more than one series of photos....
10
votes
4answers
861 views

What is the reason for a ripple effect on photos taken from a helicopter?

I took a trip on a helicopter and took many pictures with my iPhone 6 plus. One of the images was distorted with a sort of wavy ripple blur effect (other images did not exhibit the same distortion): ...
2
votes
2answers
159 views

Why aren't multi-aspect sensors commonplace on high-end cameras?

I found existing questions(1)(2)(3) about square sensors, but those would be excessive for the purpose described here. Introduction For low aspect ratio photos, e.g. 1:1, 6:5, 5:4, and 4:3, the 3:2 ...
7
votes
2answers
4k views

Lens correction in darktable when my lens isn't known?

I took some raw (CR2) photos and want to edit them in darktable. The focal length is quite low and the distortion high. Usually I correct the distortion by using darktable's lens correction module ...
5
votes
4answers
2k views

How do I get rid of distortion in pictures of distant objects photographed with a telephoto lens?

Here is a terrible example of my issue: Technical data: Canon EOS 70D + Canon EF 100–400 mm f/4–5.6 L IS, ISO 320, 400 mm, 1/500 sec, f/10. Is this issue caused by air turbulences over the water? ...
23
votes
6answers
11k views

What is the farthest a camera can see?

At what distance can a face no longer be identified using a camera? At what distance can a figure of a person no longer be captured?
0
votes
2answers
189 views

What makes these white stars appear black?

This is partial screenshot from an episode of the TV (Netflix) show Daredevil (season 2, episode 7): Note how the normally white stars of the US flag are showing up as black - albeit quite out of ...
2
votes
3answers
95 views

What are some causes for an oblate image of the Moon during total solar eclipse?

I took a few pictures during the total solar eclipse of 2019. I noticed in my images that the "width" of the Moon is greater than the "height". I know that the Moon is oblate by about 0.0012 (...
0
votes
2answers
146 views

Is distortion still significant at the distance of a selfie stick?

I'm trying to get an accurate sense of what I look like with the following methods: 1) Phone Selfie, outstretched hand - horrible distortion 2) Phone Selfie, outstretched hand + Selfie Stick, total ...
3
votes
3answers
3k 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 lenses ...
2
votes
3answers
703 views

In photo taken with a prime lens, what is the cause of the “zoomed” bokeh appearance?

This image was taken with a Vivitar 24/2 (Kiron) prime lens. The lens is sharp. The focal plane is reasonably flat, and there is barrel distortion. The bokeh balls have an oval shape in which the ...
3
votes
2answers
284 views

How to reduce landscape curvature?

My camera is a Nikon D610 which I used with a Sigma 12-24 wide angle lens. Can anyone recommend a software product to straighten up horizons with? I have attached an example where I have a curved lake ...
12
votes
5answers
6k views

Photo stretched at corners?

Can anybody tell me why the heads of the two women are stretched in the corners? What is the name of this defect and how could one avoid it? I'm not a photographer (though becoming one is one of my ...
3
votes
4answers
37k views

Is distortion on an iPhone primarily due to perspective or does lens distortion play a part, and what can be done about it?

I am researching how to correct any facial distortions seen on an iPhone's front camera. Here is my current understanding of the issue: close-up photos will enlarge nearer facial features such as ...
0
votes
1answer
74 views

Does the DJI Phantom 4 advanced has the fisheye effect on taking videos from above?

I make research on transportation systems. I'm going to use a Dji Phantom 4 Advanced in order to take videos from above and then I will georeference multiple frames. Should I take into account the ''...
5
votes
4answers
303 views

Distance-creating “lens”?

On another recent question I noted that it's theoretically possible to take "short-range" pictures that have the perspective as if they were taken at a distance, by means of a system of mirrors: To ...
17
votes
4answers
5k views

What is the difference between perspective distortion and barrel or pincushion distortion?

I've heard of: perspective distortion barrel distortion pincushion distortion mustache distortion What are these different types of distortion, and how do they relate? What causes them, and can they ...
2
votes
0answers
48 views

Were there ways to deal with distortion in the darkroom ages? [duplicate]

When people used early ultrawide angle lenses that had visible distortion, did they simply accept the fact and print it too ... or were there mitigations for things like critical architecture ...
4
votes
3answers
5k views

Why doesn't the GoPro automatically correct for the fisheye distortion?

Automatic correction of various lens distortions is possible through specialized software that takes a few camera parameters and produces an output image free of distortion. Why don't most cameras do ...
1
vote
4answers
3k views

Seeking Mac Software Solution for Correcting Barrel Distortion

I have a Nikon D7000 and a 14-24 wide angle lens which I love, but it does result, often, in a great deal of barrel distortion. I'm seeking a software solution; ideally an Aperture plug-in, to ...
0
votes
5answers
606 views

Focal length on Full frames and cropped sensors

Yes, this subject again. But I have a slightly different question and I was unable to find an answer here or anywhere else. I understand a 50mm lens is a 50mm lens ALWAYS. I understand that "...
3
votes
1answer
178 views

How do I set a lens profile to correct distortion with an inverted lens?

Recently, I started having fun with macro and micro photography by inverting a 24-85mm lens or by combining an inverted 28mm lens with a 70-200mm lens. I shoot in direct sunlight, and the results are ...
6
votes
2answers
3k views

How can I get headshot portraits with pleasing, natural perspective if I'm constrained to a short distance?

I know in a portrait photo we use distance between camera and the subject in such a way as to create a pleasing and hopefully natural-looking perspective. I think it's good on 1 ~ 1.5 meter to get a ...
2
votes
1answer
278 views

Will a clip-on zoom lens correct the distortion of a wide-angled smartphone lens?

My friend wants to shoot a vlog style series and she doesn't currently own a DSLR, so she was going to shoot with her smartphone. I am aware of the natural distortion of features (noses, foreheads, ...
3
votes
2answers
372 views

Distortion towards the edges/corners of the field of view in an image

I am taking a picture keeping the camera horizontally in landscape mode from a height of roughly 3-4 ft, acquiring the top-view of the scene. It was seen that the objects placed towards the centre of ...
4
votes
5answers
4k views

How is focal length facial distortion different on an APS-C sensor compared to a full frame? [duplicate]

From my understanding (and research) focal length affects how a face will end up looking on a photograph. Here's an example of focal length distortion on a full-frame sensor: My question is: will a ...
1
vote
2answers
1k views

Which sensor “full frame” vs. APS-C (1.6 crop) gives more distortion?

Which sensor "full frame" vs. APS-C (1.6 crop) gives more distortion using the same lens? I mean, would a 10mm lens on a full frame camera show more or less distortion than if it were on an APS-C (1.6 ...
4
votes
5answers
5k views

Does sensor size affect lens distortion?

There was recently a video posted about how different focal lengths affect portrait photography, specifically how distortion at smaller focal lengths have more distortion and are less flattering. So ...
0
votes
1answer
65 views

What is the cause of this speed-dependent distortion? [duplicate]

I took this shot using a Sony Xperia SP with OpenCamera, here are some details: Exposure: 1/800 ISO: 50 Aperture: f/2.4 focal length: 3.0 The photo was taken out of a train, at around 160km/h, the ...
2
votes
1answer
813 views

How to measure field-of-view of a camera with fisheye Lens? [duplicate]

For a camera with a rectilinear lens a simple measurement would consist of taking images from known distance of an object of known size. For example using a sheet of paper as an object set on a wall ...
1
vote
1answer
112 views

How to fix the phenomena where photos add 5 / 10 lbs or kgs to your face? [duplicate]

So, they say that photographs make you look a little heavier or fatter by 5 to 10 lbs or kgs. It does appear to be true as most of my photographs make my face look "fuller / rounder" than as it is ...
2
votes
4answers
213 views

Why do the spokes bend in this photo?

This is obviously a high frame rate photo of a very close cycling race finish. What gets me is not the closeness of the race (although the closest I've ever seen). Rather, it's how the spokes appear ...
0
votes
3answers
970 views

What is the origin of the hexagonal artifact of direct sunlight/spotlight photos?

Sometimes direct sunlight or spotlight appears hexagonal on photos/videos. What is the origin of this artifact? (source)
1
vote
0answers
194 views

How to determine the projection (Stereographic, equidistant etc.) of my fisheye lens?

I have a Fujinon FE185C057HA fisheye lens and I want to know its projection. Is there a software tool I can use to do this? I have the lens with me so I can take some pictures with it. I just need a ...
8
votes
6answers
2k views

How can I keep lines straight when taking photos of my artwork for printing reproduction?

How to take photos of my artwork for printing reproduction? I have a Canon EOS 700D and cannot seem to get them 'straight'; they always seem askew?
2
votes
4answers
1k views

Does distortion change with focus?

I'm interested in writing some software to eventually replace the current photogrammetry system I use at work. Distortion correction (among other calibrations) is an important factor in getting high ...
0
votes
1answer
225 views

Bendy distortion of straight lines in infinite mirror

I was in one of those mirror mazes where they have massive mirrors in a maze structure. However, these mirrors were lined with LED light strips, which were straight, because they were on the edge of ...
2
votes
3answers
1k views

Is there a difference between increasing focal length vs. cropping? [duplicate]

Other than the difference in the quality of the image (increased focal length will produce more quality than the equivalent cropping of the image), is there a difference? For example, if I increase ...
1
vote
1answer
629 views

How can I convert RAW files with proper distortion correction from the command-line?

I'm close to fully automating a process of stacking bursts of pictures into one image thanks to Hugin's command-line tools, however there's one part I can't automate yet, it's converting RAW into ...
2
votes
4answers
1k views

How do i take a photo of an object perfectly vertical like a top view?

I'm creating a set up that allows me to take photos of any object to capture its outlines for computer controlled cutouts. I'm no photography expert :D. I use a 60 x 60cm LED Light panel to ...
-4
votes
2answers
27k views

Why does my forehead look big in pictures vs. reality? [closed]

My forehead in reality is small—normal. Everyone I ask tells me it is normal, not big. In photos it seems too big—not even normal. I am a man. My hairstyle doesn't hide the forehead, it is up. Why in ...
3
votes
4answers
7k views

Why don't smartphone cameras correct pincushion distortion automatically?

I've previously asked why the GoPro doesn't automatically correct for the fisheye distortion, and this question is related, but different: Given that smartphones have so much processing power ...
11
votes
2answers
2k views

Why do people care about vignetting or distortion?

On every lens review there is distortion (on wide angle ones) and amount of vignetting mentioned. I would like to know why, when it is so easy to edit in post processing.
2
votes
1answer
100 views

Physical Distances at the edge of a photo compared to the center

If I take a photo with a camera facing straight down onto a flat surface (no tilt), will 1 cm of the surface be represented by the same number of pixels at both the edge of the camera and the center ...