Sharpening Basics: A Primer

August 21, 2015 G Dan Mitchell 2 Comments

(Minor updates to this article were made in February 2019.)

Sharpening is a very important step for optimizing digital photograph files. If you let your camera save images in the common .jpg format (a compressed image format that is often used on the web) the camera is applying sharpening to the image produced by the camera sensor. If you use the raw format (a high quality format that retains the original sensor data of the exposure) you will find that the photograph looks soft until you apply sharpening during the post production phase.

Sharpening optimizes the visibility of details that are already in your photograph. It is a matter of more clearly revealing what is in the photograph than a matter of creating detail where there was none. Most sharpening works by increasing the contrast between light and dark areas in the image — what we call sharpening as actually more about adjusting the relative brightness of adjacent portions of the photograph.

The image above is an example of a small section of a photograph.[1] It is a “100% magnification crop” of a tiny area from a much larger photograph made with a high megapixel DSLR camera. A “100% magnification crop” is an image displayed so that each pixel — or individual picture element — of the original photograph is displayed using a single pixel on the screen. (Things are a bit more complicated than that when using modern high-resolution monitors, though I’ll let that description stand for now.) 100% magnification crops let us look very closely at what is going on in photographas “at the pixel level.” In this case, the full original image from which these small examples were extracted would be equivalent to prints at a width of roughly 10-12 feet.

The right side of the example shows this tiny section of the photograph before sharpening. The left side shows the results of fairly typical sharpening. Continue reading Sharpening Basics: A Primer →

Photographs: Architecture, Photographs: San Francisco, Photographs: Urban/Street

Colin P. Kelley

August 21, 2015 G Dan Mitchell Leave a comment

Stark light on an old building on Colin P. Kelly Street, San Francisco

Most often when I go out to make photographs I do not have extremely specific ideas about my subject or even about how I will photograph the subjects I encounter. Usually, and especially with street photography, it is more a matter of tuning in to my surroundings and essentially hunting, conspiring to be in places where I think I might find interesting things, paying attention, and being ready to take advantage of whatever opportunities arise. On the other hand, I often do have some general ideas about the sorts of things that might interest me, and on my way to this morning on San Francisco streets I had specifically thought about a sort of image that might be black and white and which might use rather stark light a bit later in the morning — so when I saw this building on a corner near the train station I didn’t hesitate to photograph it.

What about the name of this photograph? It was simply a practical matter. I usually do not like to name photographs in ways that tell the viewer how to think of the photograph — most often I feel that if the photograph has anything to say to the viewer, the viewer should be allowed to figure that out from the visual content. (Yes, there are some exceptions.) So in this case the choice to use the words on the street sign near the right side of the frame was simply a practical decision… especially since I forgot to look for any other name on the building! However, I did wonder who Colin P. Kelley is/was. Most likely the street is named after a man known for being “one of the first American heroes of the war [who sacrificed] his own life to save his crew” in World War II. (There are lots of interesting little San Francisco streets with unusual and surprising naming histories like this.)

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Photographs: Nature, Photographs: Sierra Nevada, Photographs: Yosemite

Forest Edge, Mountain Slopes, Evening

August 20, 2015 G Dan Mitchell Leave a comment

Forest edge in evening light with forest sloping upwards toward Sierra crest peaks

This is most certainly not an iconic view, but I’m sure that many fellow Yosemite high country aficionados have been to this spot and gazed at this and the surrounding view. (Part of one Yosemite high country icon does appear in this photograph, but it is the bottom part.)

Earlier on this visit to the park I had walked out into this landscape to photograph in the meadow, on low hills, among trees, and alongside a river. As I passed by here again on this early evening I stopped and was entranced by the warm evening light on the trees at the edge of the meadow and by the further forest-covered slopes rising into the alpine zone and eventually above tree line to the elevations where there is little but rock and tundra plants. While the landscape often seems rather static during the day, at moments like this near the beginning and ending of the day the landscape changes dynamically as light shifts and highlights and then shadows subjects. I had only a brief moment to make this photograph (and a couple of others) before the light lifted from the trees and left them in shadow.

Photographs: San Francisco, Photographs: Urban/Street

Paris, San Francisco

August 19, 2015 G Dan Mitchell Leave a comment

Closed Stockton Street shops, San Francisco

Today I’ll interrupt the nature/landscape photographs in order to share another photograph of a San Francisco street scene, photographed in late July when I was there for a night street photography shoot with friends. Members of the small group began assembling early enough to start with dinner — though I arrived late and had to meet up with them post-dinner on the street. We figured that if they walked south and I walked north that we might find one another along Stockton Street in the City’s Chinatown district.

This is a favorite area of mine for photography. I love the complex and often quite worn and utilitarian architecture. Shops are jam-packed close together, and at the right times of day the streets are packed with locals. Color and texture combinations can be wild, with colorful signs, painted and repainted walls, and more. On this early evening, there were no crowds. This spot is a ways up the hill from the touristy Grant, and shops were closed or closing for the day. Shops were closed or in the process of closing, so I had more unobstructed views of the buildings.

G Dan Mitchell Photography

Sharpening Basics: A Primer

Colin P. Kelley

Forest Edge, Mountain Slopes, Evening

Paris, San Francisco

Photographer and visual opportunist. Daily photos since 2005, plus articles, reviews, news, and ideas.