101 votes
Accepted

Took my first ever 4k picture; Why is it so disappointing?

4K might be the next big thing in video, but for still photography that's just 8 megapixels, which is quite low for most cameras, and I think around the resolution of the iPhone. I have a Nikon D5300 ...
PGnome's user avatar
  • 1,059
47 votes

Took my first ever 4k picture; Why is it so disappointing?

Most cameras already have a resolution going far beyond 4K. Assuming you mean Ultra HD (3840x2160) opposed to "true" DCI 4K (4096x2160) you get a resolution of about 8MP (DCI 4K would be about 8.8MP). ...
Xudonax's user avatar
  • 571
46 votes
Accepted

Why does the Canon 1D X MK 2 only have 20.2MP

All pixels are not equal Larger pixel wells, such as those found on a 20MP full frame sensor, are able to capture more photons than smaller pixels like those on a high resolution phone sensor. The ...
Michael C's user avatar
  • 175k
34 votes
Accepted

Maximum useful resolution for scanning 35mm film

According to Ken Rockwell: Fuji Velvia 50 is rated to resolve 160 lines per millimeter. This is the finest level of detail it can resolve, at which point its MTF just about hits zero. Each line will ...
xiota's user avatar
  • 27k
28 votes

Why does the Canon 1D X MK 2 only have 20.2MP

Compromises are made in everything. Look a little harder and you can find "top" DSLRs with many, many more pixels. Hasselblad H6D-100c has 100 MP, for example. But looking at only megapixels gives ...
Dan Wolfgang's user avatar
  • 12.5k
27 votes

Are online photos safe from damage?

one of my Facebook accounts seem to have lost a significant amount of resolution Facebook (and other social media sites) compress photos while storing/displaying. Considering the amount of data that ...
suvartheec's user avatar
25 votes

What does a client mean when they request 300 ppi pictures?

I'm having trouble understanding what it means. What it means is that whoever wrote the request probably doesn't have a clue how JPEGs are rendered using most current image viewing applications. PPI (...
Michael C's user avatar
  • 175k
24 votes
Accepted

Does aliasing occur in film photography?

No. Aliasing is result of sampling, taking discrete samples or readings of a signal, at a low enough frequency that the frequencies in the input signal are confused for other frequencies, such that ...
scottbb's user avatar
  • 32.7k
21 votes

What is the resolution of a satellite image when measured in centimeters and meters?

Spatial resolution in Remote Sensing is normally expressed in distance per sample rather than samples per unit distance. The same information is there, it's just expressed as the reciprocal of what ...
smithkm's user avatar
  • 311
21 votes
Accepted

How is picture format related to sensor format resolution?

1/1.57″ is not a height/width ratio, but the diagonal of the sensor measured in inch. For some reason, camera manufacturers tend to define the sensor size as a fraction instead of simply writing 0.64″....
jarnbjo's user avatar
  • 3,282
19 votes

Took my first ever 4k picture; Why is it so disappointing?

Whoever told you about 4K probably mislead you. At least, you have the resolution right. You see, 4K at 3840x2160 is a resolution term used for video, signifying almost 4000 pixels in width. The ...
Itai's user avatar
  • 103k
19 votes
Accepted

What is a resolution unit?

This is in the Exif standard for metadata, on page 26: ResolutionUnit The unit for measuring XResolution and YResolution. The same unit is used for both XResolution and ...
mattdm's user avatar
  • 143k
16 votes

What does a client mean when they request 300 ppi pictures?

While other answers are correct regarding the general usage of ppi/dpi in digital images, there is a specific and important usage that may apply here. As you said it's for an archaeological project, ...
OrangeDog's user avatar
  • 261
14 votes
Accepted

Can a blind person resize a photo independently?

The image I uploaded was rejected because it was under 300 DPI. The DPI is just a number which has no relevance to a digital image. It relates only to printing and not the quality or resolution of ...
StephenG - Help Ukraine's user avatar
14 votes

What does a client mean when they request 300 ppi pictures?

What does a client mean when they request 300 ppi pictures? It means that they have no idea what they're talking about. Deliver full-size images as you would to any client. You can change the ...
osullic's user avatar
  • 12.1k
13 votes

Is it better to crop in Raw than JPEG?

Note that you can crop JPEG images without having to reencode them if you use tools that work with the JPEG format, such as jpegcrops, ...
Dai's user avatar
  • 233
13 votes

What is the resolution of a satellite image when measured in centimeters and meters?

"Resolution: <whatever>" means that the image contains sufficient detail to resolve an object of size <whatever> on the ground. There are multiple definitions of exactly what it means to be able ...
Philip Kendall's user avatar
  • 21.9k
11 votes

Is it better to crop in Raw than JPEG?

When shooting JPEG you usually have to option to select the size and quality of your image. For instance with Nikon cameras you can select Large and Fine. This option will give you the maximum ...
Brendan Burkett's user avatar
11 votes

Are online photos safe from damage?

Short answer: no. Especially not in the case of facebook, where you explicitely give them the right to use your images almost as they want. From their terms: Specifically, when you share, post, or ...
remco's user avatar
  • 3,161
10 votes

Why does the Canon 1D X MK 2 only have 20.2MP

Quoting from DPReview's spec sheet for the 1D X Mark II: Continuous drive 16.0 fps That means that the 1D X Mark II is pushing 20 MP × 16 = 320 MP through its pipeline every second, which is a ...
Philip Kendall's user avatar
  • 21.9k
10 votes

Why does the Canon 1D X MK 2 only have 20.2MP

Imagine yourself at the side line of a major sports event. Yeah it's bloody dark despite the stadium lights and you cannot send in your assistant to chase the athletes with a flash. You'd rather have ...
null's user avatar
  • 8,514
9 votes
Accepted

Determining the size of the smallest resolvable detail for a given camera

If you want tens to hundreds of pixels per 50 micron area, you need a microscope. Based on your object size, with that resolution, you want at least 10px/50um * 3000um/50um a 600px wide view of your ...
Brandon Dube's user avatar
  • 2,445
9 votes

How to determine the actual or "true" resolution of a digital photograph?

You could compute the Fourier transform of the picture and analyze it in frequency space. If the image was upsampled, higher frequencies will be missing in the transformed image. Note that the ...
bogl's user avatar
  • 739
8 votes

I am going to advertise on a billboard. Is 127 kilobytes good enough?

Would an image of 127 kilobytes be good enough for an advertisement that size? You really need to know the dimensions of the target billboard in pixels. It's possible that you've got a highly ...
Caleb's user avatar
  • 31.7k
8 votes

By what mechanism does a camera change its output resolution?

Let's say that with your 24 megapixel digital camera, you have selected an output size of 6 megapixels. Usually what this means is that the camera captures the scene at the full 24 MP, performs some ...
Nayuki's user avatar
  • 745
8 votes
Accepted

Do high export resolutions compromise image safety?

An image doesn't have a DPI until you print it. All it has are dimensions in pixels. Anything else is simply an interpolation of one system to another in order to display on your screen... which is ...
Tetsujin's user avatar
  • 23.3k
8 votes
Accepted

What does "12MP + 12MP Camera" mean in the specs of a mobile phone?

A quick search indicates that that "12MP + 12MP" means exactly that: two 12MP cameras. One is a "standard" camera, for the other several possibilities exist (depending on maker): monochrome, wide ...
remco's user avatar
  • 3,161
8 votes

Are online photos safe from damage?

The photos on one of my Facebook accounts seem to have lost a significant amount of resolution after they had already been posted. This is not damage, this is facebook deciding to not store the ...
TomTom's user avatar
  • 393
8 votes
Accepted

Lumix G7: Raw photos only in 1920x1440, no higher res available

Don't worry — the RAW files are the full resolution. They contain all of the data recorded by the camera. The option to change resolution is grayed out because there's no in-camera way to reduce it, ...
mattdm's user avatar
  • 143k
8 votes
Accepted

Photo quality if you upscale a low-quality photo with Gigapixel AI then downscale back

I think you are expecting far too much from Gigapixel; which is not surprising given the amount of BS in some of their marketing. Many of their marketing examples are just... umm... misleading at best....
Steven Kersting's user avatar

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