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Image quality describes how well a photograph matches a perceived technical ideal.

learn more… | top users | synonyms (1)

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1answer
2k views

How do the Pentax 18-55mm and 18-135mm compare in image quality?

I've been reading a lot about the Pentax DA 18-135mm lens and its performance compared to other lenses. I've heard that this lens is very soft at 135mm regardless of aperture. However, I've also ...
19
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1answer
1k views

What is decentering?

I have heard of a condition in imperfect lenses known as "decentering". What is decentering? When a lens is decentered, what exactly is wrong with the optical elements? What are its symptoms and ...
4
votes
1answer
546 views

Do you suggest using an extender/tele converter with a Macro lens such as Canon 100mm f2.8 macro lens?

Do you suggest using a teleconverter with a dedicated macro lens? I have tried out using a Kenko TC with canon macro lens - however I am not 100% satisfied with the "extra" magnification that I got on ...
11
votes
3answers
487 views

How can one determine the ideal resampling algorithm for a given type of image?

Was reading this question and got to thinking. How exactly can you determine what the best resampling solution is? I have a concept, albeit somewhat vague, of what the basic methods do. Are there ...
17
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4answers
1k views

Does it give higher quality to shoot in low-res mode in-camera, or to downsize high-res photos later?

Suppose you want to store your photos at some lower resolution, let's say about ~1 MB large. You own a camera able to make photos at 5 MPix and more. And, you want to have the maximum quality at the ...
11
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1answer
3k views

Does image quality of a lens depend on the camera used?

I recently bought a Canon 50mm f1.8 for my Canon 1000d. But, I find that the images are not as sharp as those I saw in the reviews or any other images taken using other cameras like the 550d and ...
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2answers
417 views

Am I being unrealistic about image quality expectations from Canon 70-200 F/4 USM IS L Lens?

I'm shopping for a 70-200 F/4 USM IS L, and took a few test shots with it. Here's a full resolution jpeg, and a 100% crop with a focus point highlighted. It was shot handheld with IS on at 70mm / F4 ...
7
votes
5answers
565 views

What parameters can I use to evaluate a “Perceptual Image Quality”?

Might be a naive question, but I want to fix few subjective metrics / parameters which would let me decide image quality. I mean, I can use some objective metrics like Mean Squared Error or Mean ...
0
votes
2answers
273 views

Camera producing blurred images under average lighting conditions

I have an old digital camera (A Fuji Finepix 6900Z) that, in automatic mode, tends to produce extremely blurry images, especially under slightly darker lighting conditions, most of the time but not ...
12
votes
7answers
4k views

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 on Digital Image Stabilizer (DIS) mode, I get white spots in pictures. This doesn't happen always. There is only an option called Pixel ...
8
votes
5answers
3k views

Can anyone recommend *freeware* to reduce motion blur by deconvolution?

Can anyone please recommend free (preferably also portable i.e. no need to install) software for Windows XP or later to improve image quality of large (12 megapixel) terrestrial (not astronomical) ...
9
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7answers
3k views

Photographic techniques to avoid chromatic aberration?

I've read several informations here on Photo SE, as well as the wikipedia article on CA. I understand that it is inevitable that some amount of chromatic aberration shows up for a particular lens, ...
7
votes
3answers
1k views

How can these photos have so high quality?

Today, I ended up in a site showing famous people faces in a very first plane. I just got impressed by the quality those photos had. What do you think are the factors you have to tweak to reach that ...
12
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1answer
1k views

Different versions of DIGIC processors, is there any difference in image quality?

While comparing the features of Canon 400D and 1000D, I've noticed that Canon 1000D has an improved DIGIC III processor, over the DIGIC II for Canon 400D. From Wikipedia: The DIGIC III Image ...
2
votes
2answers
7k views

How to improve quality of pictures that are already taken (if possible in GIMP)?

I'm not a photographer but a graphic designer. In GIMP, I only discovered two methods of improving the quality of an photo: Filters > Enhance > Unsharp Mask Noise > HSV Noise Basically, ...
2
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7answers
7k views

Is there an IQ gain from Canon's 18-135 to 24-105L?

Just got a Canon 40D body, and was about to get Canon's 24-105L lens. I hear people raving about the lens, and it all made sense until I saw a Cameralabs' review of the lens. So donโ€™t buy the EF ...
40
votes
11answers
3k views

Should I keep Image Stabilization (IS) off when I do not actually need it?

I own a Canon 7D and a EF-S 15-85 IS lens and I keep the image stabilization turned on all the time. Recently, an experienced photographer told me that this is a huge mistake because it reduces image ...
12
votes
2answers
1k views

What is the best technology for large, permanent digital printing?

Few questions: What is the best printer/plotter for printing large format images (best means best visual quality) What material and inkjet is the most permanent? I'm thinking of printing images ...
6
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7answers
3k views

Are there websites which compare digital cameras based on technical image quality?

There are lot of sites, which compare digital cameras by parameters, user experience and etc. I looking for a website which has some kind of procedure to test image quality and compares digital ...
6
votes
2answers
180 views

Fisheye Image Quality: Improves with Price?

Using a little Opteka fish attachment, I've gotten some very cool shots. The problem is that all shots get, of course, progressively less sharp as you move out from the center. I know that this is to ...
4
votes
3answers
313 views

What feature in a digital camera do I want to give better quality pictures?

Five years ago I bought the Canon PowerShot S2 IS and loved the pictures it took. All pictures were very sharp and overall I was very happy with the camera. Last year I "upgraded" to the Panasonic ...
13
votes
4answers
4k views

When shooting in mRAW or sRAW, how does the camera generate smaller files?

Most mid- and high-end DLSRs offer two or three sizes for RAW capture. When the camera is generating the medium or small sized RAW files, how does it make them smaller? Does it capture less ...
22
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3answers
3k views

With all other things equal, in a DSLR, will a larger sensor produce a sharper image?

I asked a question a while ago here about the "sweet spot" of a lens, which led to a really interesting discussion of "sharpness", the physics of light, and general image quality. 1st Question In ...
18
votes
12answers
15k views

How does the lens diameter influence photo quality?

I have tested two different 50mm lenses in my camera. One was a Nikkor 50mm โˆ…52mm. The other one was a Sigma 50mm โˆ…72mm. I took some pictures with both lenses using the same setup for aperture and ...
16
votes
6answers
460 views

Are there any important considerations for stock photos?

I have quite a few photos, some of which I consider to be particularly good. I've been thinking of putting some up on stock photo sites (that's another discussion), but have been wondering about image ...
20
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8answers
2k views

How much “noise” is acceptable in a photograph?

I've been at photography for a little over a year, and I primarily do landscape and wildlife/bird photography. Most of my work has been a learning experience so far, with few shots actually something ...
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3answers
176 views

What are some good online forums for discussing photographic editing?

What are some good forums for talking about editing photos in Photoshop or GIMP? Where do you talk about such things? EDIT: Other than here, of course.
23
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18answers
2k views

What are some techniques for hand-held image stabilization?

My zoom lens (75-300mm) is fairly slow: 5.6 at its farthest point. (I think it's 3.5-5.6, and it's not image stabilizing. I'm on a budget, sadly!) Unfortunately, my primary use for it is hand-held ...