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7 votes

Pixel Vignetting

Pixels in the center of the sensor receive light rays head on at 90 degrees, while pixels in the corner receive them at a slight angle. This part is not true... all areas of the objective element ...
Steven Kersting's user avatar
6 votes
Accepted

Does taking pictures with my iPhone 8's camera meet the required specifications for designing a book cover?

All versions of the iPhone 8 have a 12 MP rearward facing camera with a 4:3 aspect ratio. That figures to about 3000 pixels x 4000 pixels in vertical (portrait) orientation. That's more than enough to ...
Michael C's user avatar
  • 175k
6 votes

Does having larger pixel pitch (more microns) makes camera brighter at night?

ISO should mean the amount of light that must be received by the sensor to provide a proper exposure. As such, it is independent of pixel size. The 6 micron pitch sensels will receive 36/16 times ...
Ross Millikan's user avatar
5 votes

Since larger pixels increase depth of field and sensitivity, why don't we have large sensors with a low number of pixels?

... why don't we just have big pixels (and thus large sensor surfaces, because we keep the number of pixels fixed)? There are camera models with lower resolution sensors, but the reason they are made ...
xiota's user avatar
  • 27k
5 votes

What is the meaning of pixel size for sensors

The pixel size which is mentioned in the size is the size an actual physical pixel has on the sensor itself. So it gives the size the pixel takes in silicon on the sensor. What you are talking is the ...
LuZel's user avatar
  • 699
5 votes
Accepted

Image File Size Question

Your naive computation works on naive image formats (early BMP, TGA). However, most popular image formats use some form of compression, which can be lossless or lossy, and in both cases, the achieved ...
xenoid's user avatar
  • 21.5k
5 votes

Fake image so confuesd real or not

I do not know who is your "friend". But here we go. Let's play CSI, it will be fun. I am numbering the Ladies from left to right. 1, 2, 3. The Green line is projecting a shadow from the ...
Rafael's user avatar
  • 25k
4 votes

Does higher resolution in an image imply more bits per pixel?

A pixel can be understood as a 3-dimensional thing. A pixel holds information. How "deep" this information can be is the trick. Pixel Depth Here is a representation of one pixel. On the left,...
Rafael's user avatar
  • 25k
4 votes
Accepted

Does higher resolution in an image imply more bits per pixel?

Image resolution (amount of pixels) and bit depth (bits per pixel) can be changed independently. Any combination of high/low resolution and more/less bits per pixel is possible. Sometimes, however, ...
szulat's user avatar
  • 5,059
4 votes

Sensor pixel size "pixel area" any important?

That's just the nature of fractions. 5/4 (1.25) is the reciprocal of 4/5 (0.80). 1.25 - 1 = 0.25 = 25% 1 - 0.80 = 0.20 = 20% 5.95µ is 25% greater than 4.76µ 4.76µ is 20% smaller than 5.95µ So whether ...
Michael C's user avatar
  • 175k
4 votes

Image File Size Question

The reason is simple. The images are in PNG format, which implies lossless compression (like zip) of the data. Your calculations will be true if you store the image ...
Romeo Ninov's user avatar
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3 votes
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Is using image found on google (without watermark) and turning it into pixel art with some filter would be illegal?

DISCLAIMER: THIS IS NOT LEGAL ADVICE. Not having a watermark does not put the image in the public domain and so you are using those images without permission to create another artwork. This is called ...
Itai's user avatar
  • 103k
3 votes
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Large difference between number of image sensor pixels and pixels in the image from my iPhone

My iPhone 5S takes 8 megapixel images, specifically, 3264x2448 pixels. This is native size. This is speaking of still images, not the movie images which of course are 1920x1080 or 2 megapixels. ...
WayneF's user avatar
  • 12.9k
3 votes

What are these purple pixels on my Canon 60D and how do I get rid of them?

It's near impossible to tell exactly what the spots in your picture are. It is fairly easy to look at them and eliminate what they are not: hot or dead pixels. Due to the sharp outlines and well ...
Michael C's user avatar
  • 175k
3 votes

Podcast Cover Art Help!

885x1024 sounds like your contact emailed the image to you and his email software/system has resized the image. Ask them to zip the image file and send it again, or use an online service like dropbox ...
James Snell's user avatar
  • 9,709
3 votes

Full well capacity

Both approaches are correct. At least as I understand what I think you are trying to say. I'm not sure, though, what you mean by, "(4 time bigger)". Raw luminance values are monochromatic in the ...
Michael C's user avatar
  • 175k
3 votes

How can I measure a height in an image using a person's height as reference?

With Gimp you can define the image definition to about any arbitrary value, and the measure tool can display measure in the corresponding physical units. For instance in this picture the woman is ...
xenoid's user avatar
  • 21.5k
3 votes

How can I measure a height in an image using a person's height as reference?

I would just use a ruler... Scale (zoom) the image on your screen so that the person is a simple ruler measurement tall, like 1 inch... the scale of the image is now set as 1in = 1.8m. Then measure ...
Steven Kersting's user avatar
3 votes

Calculating the size of an object from a single image, given the distance from the camera

You can calculate that distance given the formula for the pinhole camera model (which is an approximation, but should work well in the cases of interest). You need to know the focal distance (which by ...
Cal-linux's user avatar
  • 219
3 votes
Accepted

Resolution on smaller vs larger sensors

The resolving power of a sensor is (roughly) its pixel/sensel density. Conveniently, for the same pixels count and aspect ratio, when you decrease the sensor size, you mathematically increase the ...
xenoid's user avatar
  • 21.5k
3 votes

Fake image so confuesd real or not

It looks real. The background is small compared to the heads of the ladies because of perspective distance. The camera has a fairly wide angle view, so that objects near the camera appear much larger ...
scottbb's user avatar
  • 32.9k
2 votes

What megapixel value is equivalent to which ISO film?

Depending a lot on the developer used as well. 35 mm Adox CMS 20II dev. in Adotech IV gives you a resolution of about 500 MPix! http://www.adox.de/Photo/adox-films-2/cms-20-ii-adotech-ii/ With 510-...
Dr. Ruediger Hartung's user avatar
2 votes

What are these purple pixels on my Canon 60D and how do I get rid of them?

These are irregular shapes and my guess is that they are not pixels, but drops of some purple liquid. If you set your camera to the cleaning mode, remove the lens and inspect your sensor with loupe ...
MirekE's user avatar
  • 5,203
2 votes

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?

Only if you still have the original data from the raw file. You cannot normally derive the original monochromatic luminance values from each sensel (pixel well) on the sensor from the demosaiced data ...
Michael C's user avatar
  • 175k
2 votes

What happens when pixels cover almost all the area of the sensor?

With conventional CMOS sensors the issue isn't so much the spacing between photosites (pixels). It's all of the circuitry on top of them (usually on the edges of each photosite) that blocks light from ...
Michael C's user avatar
  • 175k
2 votes

poor image quality

it looks like a weird design on my bare skin that is green and my bf swears its a tattoo and it's not how can I prove its not a tattoo Simple. Show him the area of skin. If it's not tatted or ...
OnBreak.'s user avatar
  • 20.5k
2 votes

Does higher resolution in an image imply more bits per pixel?

Not in common digital imaging terminology. Instead, we call bits-per-pixel bit depth. Once unpacked from whatever compression format they were stored in, digital images are usually represented as ...
mattdm's user avatar
  • 143k
2 votes
Accepted

Pixels and photodiodes

The pixels you get in a finished, camera-independent image file - a JPEG, TIFF, BMP, ...) file you get either from your camera or from your RAW processor software - are usually the results of multiple ...
rackandboneman's user avatar
2 votes

Since larger pixels increase depth of field and sensitivity, why don't we have large sensors with a low number of pixels?

The drawback is that if the sensor area is fixed, you have less pixels with increasing pixel size. Thus, the image resolution suffers. That's hardly what photographers want. Also, DoF depends on the ...
juhist's user avatar
  • 6,780
2 votes

What is a better pixel size for a scanner to use for showing photos only on screen 25um or 30um?

I assume your intent is to scan physical media, perhaps film X-rays, and display the results on a monitor? The issue boils down to resolution : Resolution of the physical media Resolution of the ...
user10216038's user avatar
  • 2,239

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