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New Apostolic Church
Photography in divine service
◼ Post-processing ↑
“A good photo is a photo people look at for longer than one second,” said Henri Cartier-Bresson (1908–2004), a French photographer and co-founder of the Magnum photo agency.
Tone curves, masking blurs, falling lines, the Right to One’s Own Image, copyright, image size, etc. Before a photo “goes out the door” there is still a lot to do and take care of. And if every beholder then looks at the photo for longer than one second (and not because they are unable to recognise anything because of the blurs, or because they want to note down the photo number as a violation of personality rights), well, then it is a good picture!
Image processing takes time. If you pay close attention to basic set-up elements while actually taking photos, you will save many hours of unnecessary work on the computer and may be able to limit your image processing to reducing the image size to an Internet-compatible 1,500 pixels. For example, moving a church pew out of the way when taking a group photo takes about eight seconds, but retouching an image at home to make the church pew disappear from the photo will take ten, twenty, or perhaps even thirty minutes ... A poorly executed tie knot in a group picture can be corrected in three seconds with the proper communication on site. Retouching the picture at home will take at least two minutes.
And only once everything is finished can the photos be published or distributed: they must be carefully selected, neatly edited, in the right format, bear a meaningful caption, and include the proper credit to the author.
◼ Photo selection ↑
“There’s small choice in rotten apples,” said William Shakespeare (1564–1616), English poet, playwright, actor, and theatre director.
Before publishing or distributing photos, it is time for quality control. One last decisive look, and the photo selection is final. Even photos that are technically perfect, carefully composed, bright, and recognisable in every facet can still cause powerful annoyance if the person(s) depicted are unhappy with the picture. With a little sensitivity, experience shows that it is quite possible to successfully carry out this quality control phase and leave out pictures that might make others unhappy or dissatisfied—or possibly even bring their blood to a boil.
If any of the following questions can be answered with a yes, any publication or distribution of the photo in question must absolutely be avoided.
- Will any of the persons depicted on the photo be brought into disrepute?
- Will the photohurt the feelings of any of the persons depicted?
- Will the photo violate personality law (key term: the Right to One’s Own Image)?
- Would I personally be unhappy about the publication of such a subject?
- Is the photo completely unrelated to the actual event it is intended to depict?
- Does the photo itself (even in association with other photos) actually have no message/picture information
◼ Histogram ↑
Many cameras (as well as photo editing programs) offer a histogram display. The histogram indicates how many areas of the image have low (= dark) or high (= bright) tones.
The histogram has two levels: the horizontal axis indicates the darkest (black) pixels on the left side, and the presence of the brightest (white) pixels of the image on the right side. The vertical axis, that is, the height of the respective bars, reflects the frequency of pixels per tonal value. A large, high reading represents a high proportion of the respective tonal value. A low, or barely perceptible reading represents few or completely missing pixels of the corresponding tonal value.
Photos that are very bright or too bright can be recognised on a histogram showing strong, high readings particularly on the right side (see above left for example).
Photos that are very dark or too dark can be recognised on a histogram showing strong, high readings particularly on the left side (see below left for example).
As a photographer I need only take a glance at the histogram, immediately after snapping my photo, to see whether the photo is balanced with respect to tonal values, or whether it is possibly overexposed/underexposed. If I detect too many unwanted dark or bright tones, I can adapt subsequent shots by way of exposure correction.
If my actual photography engagement is already over and I am limited to seeing darkness and brightness on my monitor only, then the histogram can serve as the basis for an objective correction using the image processing function “brightness and contrast” or “tonal correction” or “tone curve”.
Incidentally, the histogram is true. The image preview on the display of my camera or the display on my monitor can be affected by individually adjusted brightness or even by ambient lighting. By contrast, however, I can rely totally on the information contained in the histogram.
◼ Brightness and contrast ↑
“Bright lives by dark, and dark by bright,” said Manfred Hinrich (born 1926), a German philosopher and journalist.
Most image processing programs offer a simple—but in many cases very effective—editing function, namely one that changes brightness and contrast.
Simple and superficial corrections in the tonal range of an image can be performed using the command “brightness and contrast”. The command does not work on individual colour channels, and is therefore not very well suited to high-quality, large-scale developments in the photo lab.
In order to optimise an image that does not show the desired brightness—due to an incorrect camera setting at the time of recording—and that is only to be processed for internet use, the command can be implemented quickly even by untrained users.
In the image editing program, open the “Brightness and Contrast” dialogue box via the menu or toolbar. The existing brightness can be corrected with a slide control. An image preview allows you to see the pending edit directly. A simple click on the famous “OK” button allows you to save the edited version of the image.
Tip: the original files should be saved untouched in a special place on your computer. Ideally, you will only edit copies of the originals, such that in the case of an unsuccessful edit, the original files are still around and available for a second, third, or fourth editing attempt. — Note: data recovery or recovery after unintentional deletion, and formatting currently costs an estimated $ 1,000 or more! On the other hand, you might also purchase an external hard drive for roughly $ 100. For this reason, I recommend purchasing an external hard drive—and investing the “profit” resulting from the difference between the aforementioned cost and the cost of a hard drive in a good lens!
◼ Tonal correction ↑
Another editing function to adjust brightness is “Tonal Correction”, also known as “Shadow/Highlight Adjustment”, or “Black and White Adjustment”.
The command “Tonal Correction” can also be applied to individual colour channels (by contrast to the simple “Brightness and Contrast” function). This is how you can correct colour casts.
Using the related histogram, I will already recognise whether the image quality is good or not. As a rule, a good photo makes use of all available tonal values from left to right. The readings in the histogram will thus be distributed almost evenly. An unsatisfactory image either fails to use the full width or fails to reach the end of the horizontal axis of the histogram at one or both ends (left/right).
In order to make a good histogram out of an unsatisfactory histogram (and thereby optimise the distribution of the tonal values in the image itself), the existing pixels are spread over the entire horizontal axis by means of the “Tonal Correction” editing function. This correction achieves a higher colour saturation and greater contrast in the processed image. Black becomes true black (instead of charcoal), and white becomes true white (instead of light gray).
In the image editor, open the “Tonal Correction” dialogue box on the menu or toolbar, and correct the setting of the two sliders at the left and right ends of the histogram to increase colour saturation and contrast. To achieve this, move the tonal distribution controls at both ends of the histogram to each of the first pixel groups. Use the middle tonal distribution control to adjust the brightness values of the medium grey tone range.
◼ Tone curves ↑
“Photography is about what you see, not what you construct,” said American photographer Elliot Erwitt (born 1928), who served as both president and, for a time, vice president of the Magnum photo agency. — Too much editing does not look good on a picture as a documentation of the past.
The function “Tone Curves” is more powerful and versatile than the simpler photo editing functions “Brightness and Contrast” and “Levels” If you have the appropriate expertise and knowledge, this tool can be used to edit the low tones and high tones of a photo with much greater accuracy.
The curve in the “Curves” dialogue box shows the distribution of the grayscale values. In its initial position, it is actually an absolutely straight 45° line that connects the lower left-hand corner with the upper right-hand corner.
In order to lighten a dark picture, drag the middle of the curve upward to change the curve (this brightens the so-called mid-tones, in other words, the middle tonal range). The formerly straight line now has a slightly, or perhaps more distinctly, upward curve—and the picture has been brightened. Dragging the middle of the curve downward achieves the opposite effect—see image, above left.
In order to increase the overall contrast of a picture, the straight line must be changed into an s-shaped curve. To achieve this, the line in the high range (that is, the right third of the line) must be dragged slightly upward, and the line in the low range (that is, the left third of the line), must be dragged gently downward—see image, below left.
As with the “Levels” function, the “Tone Curve” function can also be applied to individual colour channels.
◼ Image size ↑
In the year 2018, original images taken by a digital SLR will be between 5 and 10 MB in size (jpg format) and, at 24 million-pixel-resolution, will generate image files with a size of 6,000 x 4,000 pixels. In order to display such an image in its original size, you would have to set up just over four high-resolution 27-inch monitors next to one another. — The original image from a camera is therefore definitively too large to be published on the internet without previous processing.
On most websites, the prevailing maximum view of a large image is between 1,000 and 1,500 pixels (for the longer side). An image should be recalculated to this size before uploading or before publication—and ideally not the original image, but a copy of the original image. In nearly all cases, jpg format is best suited for publication in online media.
In order to reduce the size of an image, the “Resize” function allows you to select a new output size of, for example, 1,200 x 800 pixels (or in the case of the 4:3 aspect ratio of a compact camera: 1,200 x 900 pixels) or 1,500 x 1,000 pixels (or in the 4:3 aspect ratio of a compact camera: 1,500 x 1,125 pixels). If the dialogue box allows for it, you can/should select “Keep Aspect Ratio” and “Recalculate Image”. As an alternative to fixed pixel specifications, percentages can also be specified as a reduction value in the dialogue boxes of some image processing programs.
When taking photos, the highest possible resolution should always be selected in the camera menu—irrespective of the possibilities offered by this editing function. For those of you who are now thinking about your small memory card, and the fact that you could take a lot more photos with a smaller resolution, please consider how much your camera equipment has cost, and how much—or comparatively speaking, how little—a new memory card with 32 or 64 GB of space costs. In my view, there is no reason to settle for a minimised image size when taking photographs—and thus be restricted when it comes to future use. Beyond that, a second or third memory card (and therefore more storage space) is something that fits on anyone’s wish list.
◼ Cropping and cutting ↑
And what now? Is there still too much in the picture after all? If, while taking my photos, I failed to notice that there are still a few distracting elements on the right or left side of the image (but have already attentively read the “Pars pro toto” chapter), I can even now reduce my photo to showcase its actual subject using the cropping or cutting editing tools.
Incidentally, some image editing programs feature the very convenient option of setting the output dimensions of the image in the cropping dialogue box. In this case, I can save myself the extra step of adapting the image size.
In order to crop an image down to the actual subject or remove distracting elements on the edges of the picture, I select the “Cropping” tool, enter the output dimensions of the image—if possible—and draw a selection frame in the corresponding format. A single click on “OK” will remove all distracting elements. The photo will now have the correct pixel dimensions and feature the proper image detail.
◼ Hue, saturation ↑
Using the command “Hue/Saturation”, you can optimise the hue, saturation, and brightness of the entire image or of a single colour channel. This tool is very useful for images with a colour cast. Colour casts are caused, for example, by improperly calibrated white balances, by indirect flashes off a coloured wall/ceiling, or by incorrect exposure metering.
To correct the image, call up the “Hue/Saturation” dialogue box. When correcting a colour cast, open the respective colour channel and reduce the saturation. As an alternative, all colour channels can be edited simultaneously, for example when contrasts in the original image are too strong.
When submitting raw data (raw format), a good alternative is to correct for colour casts or modify colour channels using pre-set standards. Image editing programs that can develop such raw data offer a variety of predefined parameters that can be individually optimised.