Questions tagged [pixels]
The pixels tag has no usage guidance.
57
questions
0
votes
3
answers
95
views
Resolution on smaller vs larger sensors
I was reading this paper which states that
My question is in regards to the first paragraph. I was first imagining, that if I were to try to take the same photo on a smaller sensor as on a large ...
0
votes
2
answers
98
views
Angular Displacement in Pixels to Angular Displacement in Motor Steps
Let's say I take an image with a camera, mounted on a stepper motor that can rotate it in the X-direction (Yaw).
From an image taken by the camera, I can determine the required angular displacement of ...
0
votes
2
answers
72
views
How is the picture (image signal), acquired by the sensor, shown in a display?
Let's consider a CMOS sensor with N number of pixels. For the sake of simplicity, let's consider an hypothetical Black and White sensor. Each pixel catches the energy provided by the input luminance ...
1
vote
2
answers
2k
views
Calculating the size of an object from a single image, given the distance from the camera
I was looking at other questions on here and I'm pretty sure it's not a duplicate so here it goes. I'm working on a problem where I need to calculate the size of a particular object in an image. The ...
0
votes
2
answers
700
views
How to count the amount of pixels an object in a photograph takes up
I have been trying to find out the distance of an of object from an image using this calculator https://www.scantips.com/lights/subjectdistance.html
But I need to know how many pixels long the object ...
3
votes
2
answers
156
views
Image File Size Question
Here, Wikipedia gives an example of 5 images with the same pixel dimensions of 300 pixels by 225 pixels, but with differing bit depths from 1 bit/pixel all the way to 24 bits/pixel. I thought that to ...
1
vote
3
answers
7k
views
How can I measure a height in an image using a person's height as reference?
I have an image of a person standing next to a tree. The person has a known height (1.8m). I want to estimate the tree height using the pixel ratio of the person to the tree.
I have previously done so ...
0
votes
3
answers
603
views
Does having larger pixel pitch (more microns) makes camera brighter at night?
Let's say I have a full-frame camera A with pixel pitch 4 microns and a full-frame camera B with pixel pitch 6 microns. Will using same camera lens at same exposure f/2.0 and same ISO allow me to ...
0
votes
3
answers
361
views
Sensor pixel size "pixel area" any important?
Using this camera comparison tool i got pr
If you look at pixel pitch it shows 5.95 µm and 4.76 µm however for some reason difference they display is 25% when in reality its only 20%
What is "...
2
votes
1
answer
320
views
What is the formula to upscale a photo?
Say I have an photo that is 2000 x 3000 pixels. I want a large print that is 20 inches by 30 inches. That means it will be 100 PPI.
I’ve been told to upscale my photo before getting it printed. Why?
...
1
vote
2
answers
290
views
How are focal lengths derived from camera calibration (resectioning) and pixel sensitive area related?
In camera calibration (camera resectioning process, e.g. camera calibration with OpenCV) does the result for focal lengths fx and fy depend on the photo-sensitive area inside the pixel ?
If I have a ...
1
vote
0
answers
495
views
What is the cause of these colored dots?
I recently bought a used Canon 6D with the 24-105 f/4 L USM kit lens. After shooting some outdoor pictures at night, I noticed some colored pixels or dots in the images, especially at longer exposures ...
1
vote
1
answer
474
views
Is using image found on google (without watermark) and turning it into pixel art with some filter would be illegal?
I'm working on AI collage generator with multiple png images from the internet (using google images search) and I wonder would my program break the law or not.
Program checks for watermark and omits ...
0
votes
2
answers
106
views
What is a better pixel size for a scanner to use for showing photos only on screen 25um or 30um?
I'm a dentist trying to decide what scanner to buy and I dont understand what is better by pixel size.
2
votes
3
answers
466
views
"An integer between 0 and 255 is required" when I change the value in RGB picker
So, I get this message in Photoshop when I try to insert values above 256 in RGB color picker menu, although I switched to 16 bits (image -> mode -> 16 bits per chanel). Why is that? Isn't 16 bits ...
0
votes
2
answers
125
views
What is the meaning of pixel size for sensors
I was reading into the specs of my camera, and in the manual it says that the sensor I am using (SONY EMX287) uses 6.9 μm pixel size, making it a sensor with high spatial resolution.
So I was ...
1
vote
1
answer
3k
views
Calculating the sensor size or pixel pitch of the Logitech BRIO 4K Webcam? [duplicate]
I have a Logitech BRIO webcam and want to try and calculate some of its physical dimensions like the sensor size or the physical size of each pixel.
Unable to find any info on the official site, I ...
2
votes
4
answers
903
views
Since larger pixels increase depth of field and sensitivity, why don't we have large sensors with a low number of pixels?
If I understood correctly, the DoF (all other parameters fixed) increases with the pixel surface. So to have a high sensitivity together with a deep DoF, why don't we just have big pixels (and thus ...
-1
votes
1
answer
2k
views
How to calculate Sensor Pixel Pitch?
I need to compute the “Sensor Pixel Pitch (in mm/px)” for some calculation. I have the following data available from the manufacturer:
...
3
votes
2
answers
128
views
Does taking pictures with my iPhone 8's camera meet the required specifications for designing a book cover?
I am wanting to send some pictures to my cover designer I plan on taking with my iPhone's camera. Smashword's requirements are listed here. I can't take a photo and then expand it, which could cause ...
3
votes
4
answers
2k
views
Does higher resolution in an image imply more bits per pixel?
I have been trying to understand how a better spectrum of color can be represented in an image and to avoid banding it sounds like the image would need to have more bits per pixel. When the resolution ...
2
votes
4
answers
2k
views
Pixels and photodiodes
A photodiode is the smallest element of a digital sensor, while a pixel is the smallest piece of information in a digital image. I wonder if the two terms can be used interchangeably or there are some ...
-4
votes
2
answers
100
views
poor image quality [closed]
I have a photo that has been edited in google photos or the generic option in photos on an andriod now it looks like a weird design on my bare skin that is green and my bf swears its a tattoo and it's ...
0
votes
1
answer
93
views
How can I convert a stack of images with increasing intensity to a scale that will let humans see the difference in intensity?
I have a plethora of tiff stacks from a camera with a CCD attached, I am observing the increase in the intensity of my image stack over a change in concentration, the problem that I am having is that ...
2
votes
1
answer
299
views
Large difference between number of image sensor pixels and pixels in the image from my iPhone
According to the specifications given by Apple, the iPhone 5s camera has 8 megapixels. I assume that this is supposed to mean that the image sensor has 8 million photosites, and I would appreciate it ...
4
votes
2
answers
239
views
Effective pixel readout pattern [closed]
Now there are many consumer level camera can shoot high-frame rate video. However, there is sacrificing of effective pixels as the frame rate increase. Here I'm going to take SONY RX10M3 as example. ...
0
votes
1
answer
125
views
What happens when pixels cover almost all the area of the sensor?
I think, in this question, one who give an answer has to consider 'pixel size vs pixel pitch'.
I read that in some sensors, pixels don't cover the whole sensor and my question is, when the pixels ...
0
votes
1
answer
1k
views
Can we calculate object distances by changing camera position and "measuring" pixel sizes of objects
I am not sure if this is a telemetry question or simple geometry but came across to similar questions in this forum, but I think this is a bit different; and actually "simpler" (compared to "autofocus"...
0
votes
1
answer
434
views
(compression artefacts) Pixelated photo, using Canon EOS T6 dslr
So I bought the Canon EOS rebel T6 to take pictures of products and the result is not clean as I expected.
See below a picture crudely cropped for space requierement of this site.
I took this picture ...
1
vote
3
answers
2k
views
What are these purple pixels on my Canon 60D and how do I get rid of them?
I bought this used Canon 60D for a reasonable price, however, I get these purple pixels in the top right of my image. Even though I can work around it, it is very annoying. I've tried a lot of ways to ...
0
votes
2
answers
64
views
Podcast Cover Art Help! [closed]
My Photographer Shot in Raw with 885 × 1024 dimensions. I need this for a podcast cover at 1,400 x 1400 pixels -3,000 x 3000. Please help?
0
votes
1
answer
61
views
is it possible to retrace back to the values of intensities that have been captured by the digital camera from the image's RGB values?
One can use matlab to know the RGB values's data for all the pixels. But the camera captures the data by measuring intensities at each photodiode. These values are such that they correspond to one out ...
1
vote
1
answer
216
views
Full well capacity
As I understood, the full well capacity is the maximum number of charges(photoelectrons) that can be stored in a pixel before a leakage to adjacent pixels and causing problems like blooming.
In some ...
2
votes
2
answers
723
views
What is this bright squarish pattern that I'm getting in long exposure images?
I took few long exposures of the night sky yesterday. I know about the hot pixels those appear brighter with longer exposures but this seems to be something different. Can anybody tell what it is?
...
1
vote
3
answers
1k
views
Number of pixels on longest side of email attachment?
First of all, this is a homework question for my photography class. But I have not been able to find the answer anywhere in any of my class materials or through googling. I don't mind doing more ...
1
vote
2
answers
109
views
resizing a picture [duplicate]
I entered a charity calendar competition and the picture of my cat won, but when they tried to make it larger to put on their 2016 calendar it wasn't a good enough quality. It was blurred. I was ...
0
votes
2
answers
4k
views
Pixel size at long distance
is there a formula to calculate the pixel size of a object at long distance?
Here is the scenario, I have a very small object 1cm by 1cm at 200m away from my camera. The camera has a resolution of ...
0
votes
1
answer
3k
views
How do I calculate the actual size of an image from pixels and PPI? [duplicate]
If I have drawn a line-art diagram that is 250px x 350px on a screen with 92.56 PPI (Dell U2414H - 1920 x 1080, 23.8 inch diagonal) - I'm confused as to why, when this image is transferred into ...
2
votes
3
answers
879
views
What are the exact pixel values (or ranges) for shadows/midtones/highlights in Lightroom?
In lightroom, different sliders impact different pixel intensities. I'm looking for the exact values (or approximate ranges) of the various levels:
...
1
vote
4
answers
309
views
Increasing Pixels [duplicate]
I am having a company transfer a photo to a 17" x 24" poster board. They said I don't have enough resolution to upsize that much without losing clarity. So when I take a picture how do I dictate how ...
4
votes
2
answers
2k
views
What is meant by pixels and DPI for photo submissions?
I am submitting a photo for an exhibit. They require a jpeg to be evaluated and then a print, if accepted. The rules indicate "Entries must be in JPEG format sized at 300 dpi on a CD (4” width of ...
1
vote
1
answer
355
views
Why do pixels appear when skies are darkened using the graduation in Lightroom?
I use Photoshop to create a panorama from 3-7 photos. Then I export it back into Lightroom. My RAW files are either DNGs or JPEGS when I import into Photoshop. When exported back to Lightroom, when I ...
-2
votes
2
answers
848
views
How to get photos to be under 500 pixels
How do I set my Nikon 5100 to shoot pictures that come out under 500 pixels? I want to upload pictures to my website.
3
votes
1
answer
1k
views
Why do some people say to use 0.007 mm (approximate pixel size) for the CoC on a Canon 5DM2?
The 5DM2 pixel size is approximate 0.00645mm in size and so some people talk about using 0.007mm as the CoC. I think canon said once they use 0.035mm for DOF charts, full frame normal is 0.033mm, ...
7
votes
1
answer
729
views
Comparing 1:1 zoom on a 27" screen at 2560 x 1440 vs 22" screen at 1680 x 1050
When using Adobe Photoshop or Lightroom for example, and zooming the photo at 1:1 ratio, when you work on a 22" screen at 1680 x 1050, there is an great inside zoom. On such a screen the pixel are ...
5
votes
1
answer
565
views
How can a newer camera increase ISO while decreasing pixel size?
I am a bit confused as I am considering to upgrade my canon 350D to 600D. The pixel size has reduced from 6.4 microns to 4.3 microns, however, top ISO has increased from 1600 to 6400. How did that ...
9
votes
2
answers
4k
views
Olympus OM-D developing hot/dead pixels within two weeks of purchase
I recently bought an Olympus OM-D on holiday and took around 2000 photographs in the 2 week period on holiday. On day 12 it developed some white/pink pixels on the sensor.
I've emailed Olympus ...
3
votes
2
answers
853
views
How to calculate object size dependent on distance?
I shot some images for use in a blog post. With the closeups, I ran into the problem of too low depth of field. Because I only need them for the web, I think that the easiest way to solve it would be ...
3
votes
3
answers
633
views
What is "Resolution" and how is it related to "Printing"?
What do we mean by "Image Resolution", and how is it related to printing on paper?
Is resolution related to displaying the image on computer screens too?
What is the meaning of "High Resolution"? "...
12
votes
2
answers
9k
views
What is "pixel density"?
Apparently megapixels aren't a good way to measure the camera quality, so some people are referring to a relative measuring system called "pixel density".
What specifically is this? What information ...