본 지침은 알찬 그림과 고화질 그림을 선정하는 기준을 담고 있습니다.
고화질 그림 후보는 반드시 아래의 요구사항을 모두 만족하여야 하고 위키미디어 공용에 로그인한 사용자에 의해 생성된 그림이어야 합니다.
알찬 그림 후보는 아래의 요구사항을 포함해 "감탄할한 요소"를 포함하고 있어야 하며, 반드시 업로드한 사용자에 의해 생성된 그림이 아니어도 됩니다. "감탄할한 요소"를 포함하며 촬영 당시 참작할 만한 사유가 있다면 기술적 측면에서 흠이 있더라도 알찬 그림으로 선정될 수 있습니다.
알찬 그림 후보에는 일반적으로, 특히 역사적 가치가 높고 재현할 수 없는 경우에는 더욱, 시각적 품질에 대한 제한을 두지 않습니다. 대부분의 세부적인 사항들이 보존되어 있는 적절한 해상도라면 일부 결함(색상 변경, 비네팅, 먼지 등)이 있더라도 현재 보존 상태 그대로 정확하게 보여주는 것이 최선이기 때문입니다.
일반적으로 너무 유사한 그림들 여러 개가 모두 알찬 그림으로 선정되지 않습니다. 알찬 그림의 목적은 현재까지 그림 중 가장 우수한 그림, 즉 상위 몇 퍼센트에 속하는 그림들을 선정하는 것이기 때문입니다. 전반적인 이미지 품질이 개선되면 일부 이미지는 목록에서 제외됩니다. 고화질 그림을 선정하는 목적은 생성 시점에 위키미디어 공용의 사용자가 바람직한 수준의 품질을 능숙하게 달성했음을 인정하는 것이며, 이렇게 선정 된 것은 이후 지워지지 않습니다.
유사한 화질의 그림 수에는 제한이 없으며, 고화질 그림의 등록을 취소하는 공식적인 절차도 없습니다.
좋은 사진작가는 기쁜 감정을 일깨우는데 그치지 않습니다. 그림은 사람들마다 다르게 해석되며, 지루함, 게으름, 욕망, 거부, 행복, 슬픔과 같은 인간의 감정을 일깨우기도 합니다.
알찬 그림에 대해서 어떤 사용자들은 기술적으로 평범하지만 특별한 주제에 대한 그림이 기술적으로는 우수하지만 평범한 주제를 다루는 그림보다 더 가치 있는 그림으로 인식될 수 있다고 하고, 다른 유형의 사용자들은 모든 그림이 순전히 자신의 가치만으로 판단해야 한다고 생각합니다. 예 를들어, 기술적 품질이 낮은 중요한 사건의 촬영은 종종 묘사된 사건의 중요성 때문에 알찬 그림으로 선정되는데 지지를 받으며, 기술적인 품질 때문에 동일한 양의 반대에 부딪치게 되곤 합니다.
무엇보다도, 겸손해지십시오. 귀하가 판정하는 사진은 어떤 다른 사람의 작업입니다. "이 것은 매우 끔찍하군."이나 "나는 이게 싫어."와 같은 말의 사용을 피하시는 게 좋습니다. 만일 귀하가 그 사진에 대해서 반대의 입장을 갖고 있다면, 신중하게 그 사진에 대한 단점에 대해서 논하십시오. 또 위키미디어 공용의 모든 사용자가 당신처럼 영어를 잘 구사할 수 있는 것이 아님을 고려하여 언어의 사용에 주의를 기하주십시오.
작업을 시작하기 이전에 모니터 색 보정해야 합니다. 만일 색 보정을 하지 않았다면 매우 밝은 부분 또는 매우 어두운 부분을 볼 수 없습니다. 그리고 어떤 모니터들은 지나치게 편중되게 조정되어 있어 무채색을 볼 수 없을 수도 있습니다.
아래의 완전히 검은 배경의 그림을 볼때, 귀하는 최소한 3개의 원을 볼 수 있어야 합니다. 만일 4개의 원을 볼 수 있다면 상태가 매우 좋은 것이고, 3개만 볼 수 있다면 양호한 것이며, 그 이하라면 적합하지 않은 상태입니다.
On a gamma-adjusted display, the four circles in the color image blend into the background when seen from a few feet away. If they do not, you could adjust the gamma setting (found in the computer's settings, not on the display), until they do. This may be very difficult to attain, and a slight error is not detrimental. Uncorrected PC displays usually show the circles darker than the background.
Note that on most consumer LCD displays (laptop or flat screen) viewing angle strongly affects these images - correct adjustment on one part of the screen might be incorrect on another part for a stationary head position. Click on the images for more technical information.
If possible, calibration with a hardware monitor calibrator is recommended.
It is also important to ensure that your browser is displaying images at the correct resolution. To verify this, open the full 4000x2000 version of the grid you see at the left. The grid is 8 squares wide by 4 squares high, with the squares measuring 500 pixels on each side. After zooming in to 100%, you should check if it looks reasonable given your monitor resolution. For example, if you have a 1920x1080 monitor, the horizontal width should be just short of covering 4 squares, which would be 2000 pixels. Due to scroll bars, menus, etc. the actual amount of space available will be slightly less than your screen resolution.
Firefox is known for having issues on a Windows computer where the Display setting in Control Panel have been set to anything other than 100% scaling; it is common to have a default of 125% (Medium) for large monitors. This results in Firefox upsampling everything by 25%, causing images to appear less sharp than they really are! To fix this issue, you can either change the scaling factor in Display to 100% or go to about:config (in the URL bar) and change layout.css.devPixelsPerPx to 1.0.
그림에 대한 요구 사항
고화질 그림은 반드시 적합한 라이선스에 입각한 저작권에 의하여 위키미디어 공용에 업로드 되어야만 한다. 모든 라이선스에 대한 규정은 라이선스에서 살펴볼 수 있다.
GFDL으로만이거나 GFDL-비영리으로 된 그림은 재사용이 힘들어 알찬 그림에 등재되지 못한다.
Images should have at least 2 real megapixels of information (with the exception of animations, videos, and SVGs), for example, 1600 × 1250. For "easy to take" images, reviewers may choose to demand more if the image would benefit from it. This rule excludes images computer generated and constructed using a free licensed source code available in the image description.
Images should not be downsampled (sized down) in order to appear of better quality. Downsampling reduces the amount of information stored in the image file. Downsampling images of living persons can be advisable if the images would otherwise show details of the body (e. g. skin, teeth) in unacceptable magnification, which could be considered offensive or violate the person's rights. However for Featured Pictures, the original non-downsampled version is preferred.
Graphics located on Commons may be used in ways other than viewing on a conventional computer screen. They may be also used for printing or for viewing on very high resolution monitors.
We can't predict what devices may be used in the future, so it is important that our best pictures have as high a resolution as possible.
Use high-quality settings in your camera and imaging software. For example, set JPEG quality "superfine" in camera, or, if your camera can save images as RAW files, you can process these into uploadable JPEG files with appropriate software later. Use a JPEG compression quality between 80% and 90% when saving finished copies for upload, depending on acceptable file size.
When saving an image between multiple editing steps, use the editing software’s native format, or use a standard lossless format such as TIFF or PNG if you need to open the image in different editing software. Repeatedly editing and saving as a JPEG image will gradually lose quality.
Do not save edited JPEGs with a significantly higher quality than the original—doing so increases an image's file size but not its quality.
이 그림은 JPEG 압축 수준이 낮다.
This image has a strong JPEG compression level and visible artifacts.
Noise
Chromatic noise
Luminance noise
Visible grain
Scratches, dust and dirt
Spots
Images should not have distracting amount of noise when viewed in full size.
To reduce noise, use the lowest practical sensitivity or film speed (for example: 200 ISO film is less grainy than 1600 ISO!).
If the photo was taken in unique circumstances and cannot be repeated, the image can sometimes be improved by filtering.
Noisy image taken with a high ISO and fast shutter speed.
No noise here, the image was taken at base ISO with a longer exposure.
Exposure
Overexposure
Blown out highlights
Underexposure
Lost details in shadow areas
Considering the circumstances, images should be correctly and appropriately exposed.
In correctly exposed images, details in a significant part of image are retained.
It should be noted that exposure may serve a creative purpose, and this guideline should be evaluated with understanding of the idea or intent of the image. Exposure refers to the shutter diaphragm combination that renders an image with a tonal curve that ideally is able to represent in acceptable detail shadows and highlights within the image. This is called exposure latitude. Images can be on the low side of the tonal curve (low range), the middle (middle range) or high side (upper range). Digital cameras (or images) have a narrower latitude than film.
Lack of shadow detail is not necessarily a negative characteristic. In fact, it can be part of the desired effect. Burned highlights in large areas are a distracting element. When shooting with a digital camera, inspect the histogram. In challenging circumstances you may be forced to use overlap several photographs with different exposures – this is called HDR stitching.
Quality images must have reasonable colors and shouldn’t be too bright. Note that this does not necessarily mean natural colors.
Color balance can be often corrected by editing programs.
When taking Photographs in a RAW image format, it is possible to adjust the white-balance in post-production, i.e. on the computer, without any loss in quality.
Every important object on the picture should be sharp, considering the idea of the image.
The overall image should have clearly defined focus, for example, the main subject is in focus and the foreground and background are out of focus, or else, the whole scene is in focus.
Depth of field is often low intentionally. If in doubt, ask.
"Depth of field" (DOF) refers to the area in focus in front of and beyond main subject. Depth of field is chosen according to the specific needs of every picture.
Large or small DOF can add to or detract from the quality of the image. Low depth of field can be used to bring attention to the main subject, separating it from the general environment. High depth of field can be used to emphasize space. At a given subject distance, short focal length lenses (wide angles) yield larger DOF than longer focal length lenses (telephotos). Narrow apertures (high f-numbers) yield larger DOF than wide apertures (low f-numbers).
Bad problem with focus.
Correct focus and depth of field.
Shallow depth of field serving a purpose.
Motion Blur
Too long exposure: image has become blurred because of hand shaking or subject moving too fast.
Motion blur should have a purpose, most often to emphasize motion.
"Movement control" refers to the manner in which motion is represented in the image.
Motion can be frozen or blurred. Neither is better over the other by itself – it's representation that matters. Movement is relative within the objects of the image. For example, photographing a race car that appears frozen in relation to the background does not give us a sense of speed or motion, so technique dictates to represent the car in a frozen manner but with a blurred background, thus creating a sense of motion. This is called "panning". On the other hand, representing a basketball player in a high jump frozen in relation to everything else, due to the "unnatural" nature of the pose may well be a good photograph.
Adequately handled motion.
Subjects blurred.
Lighting
Distracting reflections (usual problem with built-in flash)
Lighting should be appropriate for portraying the subject.
Light is said to be the most important ingredient of a photograph, and quality images are expected to have it right. The quality of a shot may depend on conditions beyond the photographer’s control, like weather at outdoor shots or stage light.
Contrary to general belief, front lighting is not usually the best light as it flattens the subject. Side lighting often gives a better “texture” to surfaces. The best daylight is often early morning or late afternoon, or on a slightly cloudy day.
When photographing in strong light, you may want to soften the shadows by using “fill flash”.
Soft, nicely blended shadows, and lighting from different angles shows that subject is not flat.
Harsh and flat lighting resulting from the camera's pop-up flash.
Editing
Unnecessary or inappropriate use of artistic filters and effects. Editing programs have wonderful artistic filters and scripts. Unnecessary use of these, however, can be detrimental to the image.
Digital manipulation for the purpose of correcting flaws in an image is generally acceptable, provided it is limited, well-done, and not intended to deceive. Typical acceptable manipulations include cropping, perspective correction, sharpening/blurring, colour/exposure correction, and removal of distracting background elements.
Extensive manipulations must be clearly described in the image text, for example by means of the {{Retouched picture}} template. Unmentioned or misrepresented manipulations, or manipulations which cause the main subject to be misrepresented are never acceptable.
A part of post-processing includes HDR and tonemappings. Some like using strong HDR effects for images shared online, but the possibilities of such techniques are often used in a way that means that images have little resemblance with reality.
On the other side, some subjects such as church interiors often require further editing work and the combination of multiple images to avoid over- or underexposure. In such cases, extensive post-processing can even be desirable if done with appropriate care.
Overprocessed.
Well-handled dynamic range.
Composition
Unbalanced composition
Unclear subject
Non-existent subject
Too tight crop
Too busy
The arrangement of the elements within the image should support depiction of the subject, not distract from it.
Foreground and background objects should not be distracting.
The subject should not be cropped, unless it is only a specific part of the subject that is of interest. Foreground and background objects should not be distracting. Objects in front of the subject shouldn't hide important elements and background elements shouldn't spoil the composition (for example that the streetlight doesn't "stand" on someone's head).
The Golden Ratio and Rule of Thirds are common guidelines for composition that have been inherited from painting. Centering the subject is often considered a negative practice. Subjects of interest are placed in one of the "interest points", where horizontal and vertical lines intersect (4 interest points are created). Horizons are almost never placed in the middle, for they "cut" the image in half. They are placed either in the upper or lower horizontal line. The main idea here is NOT to center the subject without a very good reason (such as symmetry).
Typical use of the rule of thirds.
왜곡
Tilt
Perspective distortion
Barrel distortion
Images should not be unintentionally tilted.
Images of architecture should usually be rectilinear.
Perspective distortion should either have a purpose or be insignificant.
The human brain is a sensitive detector capable of spotting even a small tilt. Falling trees, towers and inclined water surfaces rarely improve landscape photography.
Tilt can be easily corrected in almost any photo editing software. Various more complicated distortions can be adjusted in programs such as hugin and Panorama Tools. If you don't have access to suitable programs or don't understand them, ask at the Commons:Graphics village pump and someone may be able to process the image.
Distorted perspective.
Perspective corrected.
Stitched images, panoramas
Height
Guideline: Panoramic images need to have a minimum height of 800px.
Stitching
Common problems: Stitching artifacts. Colors or luminance are not consistent across the image. Horizon line sinusoidal or even more complicated shape.
Guideline: Getting a good panorama ready takes time. Recent releases of programs like hugin and Enblend make simple errors like bad alignment and ghosts at blurred seam lines less common than they used to be, but parallax errors and more intricate quality problems still occur. Two examples:
The ingredient photos were taken with a camera not in panorama mode, and camera-bundled software was used for the top stitch. One notices that the left part is darker, due to the camera exposing each photo individually. This could be dealt with by adjusting brightness before stitching.
More subtle errors are at the right of the castle, where there appear to be two vertical bands in the sky. Look where these bands touch the hill, at the middle one the stitching program misaligned, producing a ghost. Also, the program feathers the transitions. While this avoids a visible edge, one can see that in such feathering region, image noise is reduced, which makes these parts stand out from the rest of the image.
The bottom image shows that using different software, the photos can be stitched without such errors.
Lighting
Common problem: different exposure in different images, leading to overexposure or visible differences in brightness and posterisation.
Guideline: Even when photos are taken with the camera in panorama mode, unless one chooses an overall exposure for all images to handle the brightest part of the brightest image, then blown highlights are likely.
Ciemniak panorama.jpg
If possible, set for underexposure, as well as panorama mode. Expected advances in software based exposure correction may soon make panorama construction viable from a photo series not shot in panoramic mode. Until then, use the brightest part of your panoramic scene to set the in-camera exposure when shooting.
Some software provides blending algorithms that make the seamline invisible. But if the brightness of the original photos differs significantly, one still notices a transition in between photos. A few minor misalignments notwithstanding, this is what the top photo shows.
Some programs incorporate brightness adjustment for the photos, but the algorithm has to be designed carefully otherwise one can end up with posterisation effects like the purple and light blue patches in the clouds on the left in the bottom image.
Vignetting
Blending-only programs can do away with seam lines and smooth structure using feathered overblending, but to correct lens vignetting one needs a radius-dependent brightness correction.
Deliberately strong vignetting
The left image shows a technically acceptable stitch, except for the vignetting effect which has been strongly exaggerated. Good stitching programs incorporate vignetting correction. Make sure to incorporate good vignetting correction. Pre-processing the input images is less elegant, but one can obtain good results. In the sky can be seen three bright areas, separated by two darker bands. These correspond to the middles and the sides of the three original images. Although programs like Enblend remove visible seam lines, they do not remove vignetting effects. In the sequence hugin-enblend it is at the hugin stage where vignetting has to be corrected, either inside a recent hugin version or as already corrected input.
On the right is a more subtle example of vignetting, most visible in the sky, where one can see three bright areas from left to right separated by two darker bands. These correspond to the middle and the sides/corners of the three original images.
See in the photo below how the sky brightness spans the spectrum without being burnt out, but still the sky brightness has a wavy structure, most noticeable in the left part.
Tatra Mountains Panorama 01.jpg
Camera positioning
For the left stitch, the photographer captured the bottom part of the church, then stepped left and took a photo of the top part. The seam line is visible in the windows just below the clock, and one sees shifts in different directions in the middle and on the tower structures. Stitching software is not meant to cope with such parallax error as the problem here is located behind the camera, and the way out in this case was the availability of matching photos, albeit from a different perspective, to create the image on the right.
Image alignment
Proper alignment of images is a crucial first step and has been achieved in this view taken in the Western Scottish Highlands. But the exposure differs between images and cameras have vignetting, both make seamlines visible. And as these photos have been aligned regarding the distant features, some parallax errors can be seen at seamlines in the foreground. There exists software that makes such seams disappear and the parallax errors can be concealed by choosing a suitable seamline.
Composition
Common problems: Panoramas frequently lack a central focal point. If taken within urban settings, much of the scene may be uninteresting with unattractive features such as rubbish bins and light poles almost impossible to avoid.
Color space
Different color spaces cover different colors and yield different rendering.
Different color spaces exist, which determine how the colors in an image are stored and displayed. sRGB is most common and compatible, while other color spaces, notably Adobe RGB, allow more colors but are less compatible, and must be correctly supported by users' computers.
Simplest is to use sRGB, which is usually default on Windows and Linux, but must be selected when saving files on Mac (prior to OS X 10.6). For further options, read on.
Images should either be in sRGB (either untagged, or specifically tagged as sRGB), or, if in another color space, explicitly tagged as such. Tagging means either including an Exif tag with the name of the color space (options are "sRGB", "Adobe RGB", and "other"), or including an ICC profile, which explicitly specifies the color space. Including an embedded profile is safer, as Exif tags are not always respected by web browsers. Untagged non-sRGB images ("mystery meat") will not render correctly on the vast majority of computers.
For most Windows and Linux users, sRGB is default unless changed, and untagged images will generally be sRGB. However, Mac users should take care that their images are exported in sRGB, and not "Generic RGB" or "Apple RGB".
Best color spaces are sRGB or, optionally, Adobe RGB, which is wider, as these are standard color spaces and hence easiest to support and for other editors to use. If using a non-sRGB color space – say for greater color range – consider making an sRGB version of the image for greater compatibility.
Technical details
It is safest to use sRGB: which is the default on most computers, including Windows and Mac OS X 10.6 and later. Images in other color spaces will not render correctly at all in many web browsers; color profile support is included and enabled by default in Safari, and in Firefox 3.5, but not in all browsers.
Untagged non-sRGB images will not render correctly except by chance. Notably, untagged Mac images prior to OS X 10.6 used a different color space (Apple RGB prior to OS X, "Generic RGB" in OS X prior to 10.6), which notably included a gamma of 1.8, rather than 2.2; these images thus appearing dark when viewed on non-Mac computer that assumes sRGB (with gamma of 2.2).
If the location is difficult to obtain (eg. in the wilderness areas), you may have the choice of giving the general location (to 3 decimal places or fewer, as appropriate), use {{Location estimated}} or simply mentioning a nearby geographical feature (eg. valley, river, mountain range) or a settlement that would help to identify the location.
Photos that can't or shouldn't be geocoded include those which would show the locations of endangered plants and animals, military installations, studio photos or locations that should be hidden to respect rights of privacy. To communicate this in the image, you may wish to use {{Location withheld}} template.
Exif
See Commons:Exif for help on using and editing Exif metadata.
