Questions tagged [artifacts]
Elements of a photograph that are generally undesirable or have a negative impact. Examples include noise, flare, dead or hot pixels, sensor "spots", reflections inside the camera/lens system, etc.
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What is moiré? How can we avoid it?
What is the image defect called "moiré"? What causes it, and how can we avoid or reduce it? Is it related to "false color"?
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How can I stop my HDR shots looking so fake?
All my attempts at HDR come out looking remarkably fake, how can I reduce the halos effect?
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What is noise in a digital photograph?
What kinds of effects are present in digital images that are referred to as "noise"?
What are the different sources of noise?
What causes each type of noise?
What are the characteristics of the ...
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Taken a picture of my monitor while spinning in circles - why is it distorted?
I just found a picture again I took years ago, and I'm wondering what's happened ever since then - I hope this is the right place to ask!
I sat on my swivel chair and spun a few times, while taking ...
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What could be the reason for these block-like artefacts in the blue sky?
I'm using the Huawei P10 with its Leica camera.
Recently I noticed very visible large block-like artefacts in the sky. These artefacts are present on some pictures, but not on all, and they are ...
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Why do photos of digital screens turn out the way they do? [duplicate]
When I take pictures of a screen at school or at my house, they turn out really weirdly. When blown up to 100%, they look fine, but when they get sized down, they look really weird, here is a ...
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What are jpeg artifacts and what can be done about them?
I know JPEG is a "lossy" compression algorithm that discards information in order to save space. What is the visual impact of this? I've heard of "JPEG artifacts". What do these look like?
Are there ...
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What causes these white, squiggly lines in my photos?
I took this self portrait this morning getting out of the shower. There are some white squiggly lines: two near the sink and one on the door handle. What causes them?
The picture was taken with a ...
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How can I avoid soft dull "spots" in my pictures?
Recently, I've been doing a lot more photography, particularly with my 100-400mm telephoto and 16-35mm wide. I am skilled enough that I can capture the shot mostly as I want with just the camera gear, ...
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What causes these inconsistent dark bands in some of my photos from an indoor event?
Yesterday I took photos of an event at school.
The lighting was poor so I increased the iso to 3200,
shutter speed was between 80 and 250 and the aperture between 2.8 and 4.0.
Canon EOS500
about 10%...
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Why do I see this yellow color shift at high ISOs and fast shutter speeds? [duplicate]
I recently purchased a full-frame DSLR with a reported highest ISO of 204,800. I’m intrigued by the possibilities of the high ISO range and how far Lightroom and Aperture (I use each of them) can ...
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Why does using flash sometimes create these white spots in the photo?
I have an Olympus FE-190. When I take a picture with flash in Digital Image Stabilizer (DIS) mode, I get white spots in pictures. This doesn't happen always.
There is an option called Pixel Mapping, ...
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What causes and how can I avoid this moiré pattern in a composite night sky photograph?
I'm new to taking star trails, and fairly new to photography in general.
After my first attempt at taking a star trail, I composited them in Photoshop and when I merged the layers I got this pattern ...
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is it normal to get significant lens flare with a 50mm f/1.8 prime lens?
I've purchased a Canon EF 50mm f/1.8 II. But I'm really disappointed in the results, especially when using it for night photography. :(
In my night shots a lot of lens flare appears in my photos. I'...
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How can I avoid green flare on my sunrise photos?
I took a series of sunrise photos. Once the sun actually came above the horizon, the brighter the sun became the more apparent and brighter a green flare (glare?) appeared. How can I avoid that?
...
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Why does the left windmill have too many blades?
Ok, check this shot out:
These are the 3 windmills in Marshfield Massachusetts. It was shot from Provincetown, MA about 35 miles away. (I wasn't out to shoot them, I was shooting Right Whales... I ...
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How to avoid jpeg compression artefacts when saving photos in web resolution?
When I save a web-resolution image (for example, 1920×1024px), flat areas tints often have damaged shades of color. I'm saving in Photoshop CS4 with quality 2 in standard mode, because I need the ...
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Why are red lights in night / city scenes coming out as big red blobs?
I've noticed that in a lot of my night shots of cityscapes, red lights (e.g. neon signs on buildings, etc.) tend to come out as big red blobs:
The above was taken with my Canon 500D.
What can I do ...
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Why does this satellite image of an airplane in motion show red, green, and blue bands with strange artifacts?
I stumbled upon this satellite image (http://goo.gl/Wv503u) capturing a plane in flight over a city.
I'm having a little trouble explaining the color effects caused by the aircraft motion.
What I ...
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Where does this reflection come from in a long exposure shot?
Using a long (10 second) exposure I found I was getting an odd "reflection" in the picture, where the brightest object leaves a residue in the opposite part of the frame.
You can see it here:...
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multi-strobe-like motion blur outdoors?
This photo (cropped here) appears on p. 48 of the October 2020 issue of the Experimental Aircraft Association's Sport Aviation magazine. The upper blade of the propeller shows the motion blur that is ...
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What causes these streaked rays from light sources?
I recently bought an LG G4, whose camera can shoot in an auto and both manual mode (I can manually set the iso, aperture). I shoot 100% of the time in auto.
It takes better than average photos at ...
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What's the reason for this exceedingly blue reflection from buildings in this image?
I've noticed that lately my camera has some issues with blue neon lights. Here's an example shot.
You can notice the effect in the reflection of the water in a building and in the blue dome of ...
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What causes faint circles in astrophotography images?
When processing an astro-images taken with a Canon 450D and prime focus, I often end up with a series of faint circles radiating outwards from an off centre point. What are they and how do I get rid ...
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How do I take a photo so the moon doesn't have bright "rays"?
Any advice on how to remove moon "rays"? (Looking to learn how to take a photo without them, not remove them in post)
Artistic opinion - is it too underexposed?
The picture was shot at shutter speed ...
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Why do my photos look like they're painted?
I'm not an expert, but all the photos I take look like they've been painted. It doesn't look like normal blur.
I'm using a FinePix S2500HD and the following photo was taken at 1/2000 exposure. I ...
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How do I eliminate lens flare in my pictures?
I have taken a few pictures that show these circles, and I'm getting very annoyed at this problem. Seems most common on sunny days. This particular picture is not my own, but it is a good example of ...
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Why is my camera showing a lot of stuck red and white pixels?
After shooting for one hour with my Rebelt2i + Tamron 17-55 f2.8, I went back home and checked pictures on my computer.
For every single picture, there are a lot of 'dead' pixels at the same location....
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How can I avoid circular banding artifacts in clear skies when de-noising?
I photograph in RAW, and convert using Darktable. Camera happens to be Nikon D40, 55-200mm lens. For a small number of photos, especially of clear blue skies, I cannot reduce noise without introducing ...
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How to edit photograph to remove flashes of light / glow / glare?
How can I remove the "glare" on the musicians in the photo below using Photoshop?
I do not have the relevant vocabulary to express what this "glare" really should be called.
I am not a photographer ...
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Why do my photos show blocky gradients, even in RAW?
I am learning to use my new DSLR, a Sony a57 with 18-55mm kit lens. I was shooting last night at sundown, and after exporting the RAW images to Lightroom, was surprised to see the gradient as showing ...
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Why do I get horizontal grey bar with flash at shutter speeds slower than max sync speed?
I'm a total newbie to flash photography, and I am just trying to do some test shooting with Canon Speedlite 580 EXII using my 7D.
I saw on the user manual that the maximum sync speed is 1/250 sec.
...
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Why do I get dark horizontal lines (stripes or bands) in bad lighting with my Fuji X-T1?
Can anyone explain why I get these lines when taking photos in bad/weak lighting? Here are some photos.
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Dust-like speck visible every few pictures — is it dust, or worse?
I seem to have to dust-like speck on my Sony Cybershot S950's lens, but it appears randomly every few pictures. Could something be going bad internally?
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How can one correct intensity flicker due to AC line frequency?
Is there a good image processing method to get rid of the horizontal stripes in the images taken under fluorescent lighting? These stripes (flicker) occur when you take pictures indoors due to the 50 ...
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What causes these green dots in my image?
I just received a 35mm f/1.8 DX lens for my Nikon D50 for Christmas, and took some shots where the lights on the tree were the main source of illumination. Almost all of them exhibit very prominent ...
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Why are those green spots on my photo?
Took a pic with my 35mm Nikon lens last night, and got this light artifact. Is this something normal? Reflection? Is it dirt on my lens? How do I prevent this from happening? I think it only happened ...
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What is this pattern artifact in a Hasselblad H4D picture?
Shot some shoots with Hasselblad H4D-50 and in (at least) one of them the following artifact(s) appeared:
Of course some questions arise:
What is this? (moire?)
Why it happened? (aside of lack of ...
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What does it mean to excite aliases?
I recently came across the phrase 'excited aliases.' The phrase seems to be related to lens sharpness in some way. While a web search turns up the phrase a few times, I am unable to locate a decent ...
user5283
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Are these blotches of wrong color caused by a corrupt SD card?
My old camera was taking images that had blotches of the wrong colors when zoomed in, and I take a lot of macro pictures. I bought a new camera and put my old sd card into it and now it's doing the ...
Carol
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Horizontal banding pattern near sun: sensor flare?
Following is a crop from a RAW shot, developed in Lightroom 5.7, into a setting sun from a Sony A77II – ISO 100, f/5, 1/20s, with a TTL fill flash.
In the darker regions near the sun a series ...
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Time-varying artifacts in long exposure: is it the sensor?
I have just made my first attempt to photograph the International Space Station, and I clearly need to improve my technique. Here are the details:
Body: Canon EOS-M (1)
Lens: EF-M 55-200mm at 200m, f/...
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What is "veiling glare"? How does it affect my photos, and how can I avoid it?
Someone mentioned that "veiling glare" or "veiling flare" was to blame for reduced contrast in a photo. What does this mean exactly?
What causes veiling glare, and how can it be avoided? How does it ...
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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 ...
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What causes the spots in my IR photos?
Below are images I've shot recently while experiminting with IR photography. The first is an IR image with +2 stops of exposure and a custom white balance based on the bright part of the tag on the ...
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How do I get rid of these different spots after sensor cleaning?
I've just cleaned sensor on my Nikon D40x for the first time using sensor swabs and Eclipse solution.
Here is a picture taken before cleaning and after .
Dark spots on the first photo do not appear ...
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What is the strange wide, bright line across this photograph?
I shot this image on a GoPro camera in time lapse mode. It was at ISO 100, f/3.6, 1/950sec. I also happened to be moving the camera at very high speed during the shot. What is the ligher horizonal bar ...
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What caused the strange "wave X" lines in the out of focus background area in this photo?
Can anyone explain these wavy lines forming a across in the photo?
I used a Nikon AF-S DX 18-140mm 3.5-5.6G ED VR at 140mm, ISO was set to 160.
Here is a 1:1 ...
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What is the cause of inclusions in my bokeh?
I was doing a lens review an two of my lenses showed these rather unsightly inclusions in their bokeh. There are two different lenses.
EDIT: The third lens I have tested also seems to have this ...
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What is the difference between Diffraction Spikes and Lens Flare?
When Googling for lens flare, one often finds images that also include stars (rays / diffraction spikes), like this:
What is the difference between diffraction spikes and lens flare and are the two ...
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