The last article on curves looked at linear adjustments and how those adjustments affect the image and the histogram. So now we’ll take a look at some nonlinear adjustments within the curves adjustment tool found in many photo editing software packages.

We’re basically building on our basic understanding of the histogram and our knowledge of linear curve adjustments to take the next step into nonlinear adjustments (the curvy curves).

NONLINEAR MANIPULATIONS

What I’m going to show here are some very basic curves at each extreme. The single bend and double bend curves are most commonly used during post-processing, but these are not the only options. Curves can have a large number of set points, bends, and inflections — it’s just not feasible to cover every possibility in an article like this.

SINGLE BEND CURVES

The simplest form of a nonlinear curve is accomplished by moving a mid-tone location toward the upper left or lower right corner, forming a basic arc with a single bend. Essentially, your black and white points remain fixed while your mid-tones become lighter or darker (aka: brightness). Also note that one end of your tones will take on more contrast while the other end will lose contrast due to the change in slope of the curve (remember: vertical = high contrast, horizontal = low contrast).

This can be used to brighten or darken the overall image if you want to maintain your highlights and shadows at their current values.

DOUBLE BEND CURVES

Also known as the “S-Curve”, this curve manipulation pushes one section of tones brighter and another section of tones darker (aka: contrast). Again, you can maintain your black and white points, but you also maintain some middle tone where the curve crosses the diagonal. On the note of contrast again, be aware that you will sacrifice contrast in one area to gain it in another.

This can be used to raise or lower the contrast of the overall image with a focus on the mid-tone areas. The bright/dark tone changes of the highlights/shadows are amplified by the mid-tone slope change — so it doesn’t take much to really change the contrast.

APPLYING NONLINEAR CURVES

The beauty of the curve adjustment is that you have such a wide range of possibilities — much more dynamic than a single slider adjustment. To apply curve adjustments, you simply click a location on the curve and drag it to the desired location. The curve will bend on its own based only on your set points. You can continue to add set points until you have the desired result.

Using the example image above (middle of series), here’s one possible curve that combines linear, single bend, and double bend curves. Keep in mind that I haven’t applied any basic adjustments and what you’re seeing is pure curves from an unprocessed raw file (except for the b/w conversion).

Notice that I used a double bend curve to increase contrast. Combine that with a single bend curve to increase brightness. And combine that with a linear adjustment to set my black and white points. I’ve also placed several extra points on the curve in order to bend it into the shape I wanted while maintaining a smooth transition.

As you work with curves, you’ll noticed that they sometimes have a mind of their own. Extra points will help shape the curve and provide you with the ability to make the adjustments you want. On that same note, too many set points can lead to choppy and lumpy curves. Non-smooth transitions generally begin to produce strange contrast artifacts that are easily seen in the image.

A Guest post from Lisa Newton by Lisa Newton Travelin’ Local

My business website is a hyper-local niche online lifestyle magazine, Travelin’ Local, where I features countless walking and bike riding maps, including a judicious quantity of photos to accompany my stories for the area that we specialize in, which includes Los Angeles and environs.

Eager to figure out and learn how to Geo-Tag my walks, I was amazed at the lack of information and knowledge regarding the how’s, what’s, where’s, when’s, why’s, and who’s, as it pertains to this technology and how to integrate it into stories, blogs, and websites. So, I took matters into my own hands and learned the old fashioned way; by investigation, experimentation, and implementation.

The first stop on my learn-by-doing adventure was, of course, the king of maps, Google.

Simply put, I would walk a route, and keep copious notes of the streets I was walking, the turns I made, or the landmarks I saw along the way.

While taking pictures at the same time, my goal is to obtain the best possible visual record of where I’m going, and where I’ve been. Sometimes, I would just shoot the street sign to avoid the interruption between story and record keeping, as well as having to not write anything down.

After I got home, I’d pull up my Google Maps and create a new map based on whatever particular story I was working on. You need to have a Google account in order to create a map, but that’s a snap to set up.

Once you have an account, go to My Maps and “Create a Map.”

moves the map around

creates a place marker. By using the dropdown menu, you are offered many choices for this icon.

the third and final option is the best of all. With its line tool dropdown list, Google provides several methods for mapping your route:

1. Draw a line, which allows you to draw any type of line anywhere on your map
2. Draw a line along roads: Just as the name suggests, the tool follows lines along established roads. Here it pays to mark your route by clicking often. Sometimes, Google tends to have a mind of its own.
3. Draw a shape: If you need to map an area rather than a route, this freehand tool allows for that.

Once you determine which tool suits your purpose, you’re ready to start creating.

After you get your route done, the fun part starts by adding points of interest, photos, comments, information, links, and any other necessary information to create the story you want your readers to enjoy.

Within the place marker box, Google gives you three options to take advantage of:

• Plain text which is just as it reads; you type and it appears
• Rich text parallels WYSIWYG, giving you the ability to add images, make font changes, and add bullets, etc., to your place maker. If you’re not an expert at coding, which is where I tend to live, this tool is a lifesaver.
• Edit HTML allows you to get behind the scenes, so to speak, and change the coding or add coding as you deem fit.

Basically, if you’re skilled at coding, you can create a webpage for each place maker.

As far as geotagging your pictures within Google Maps, it’s a totally manual project. You place the marker where the photo was taken, and when you hit the image icon, an html box pops up. Each picture is uploaded via the Rich text tool, so each picture has to have its own URL. When I add pictures to Google Maps, I upload them to my blog first, cut and paste the URL, and then add them to Google.

Once you finish your map, the best part is that you can now embed it into your site, or share the link with friends:
View Hollywood Walk of Fame in a larger map

It’s a time consuming process, but one well worth the effort. I love sharing my walks with my readers, and Google Maps is one way to do that.

Classical or contemporary; architectural photography can be as challenging as it is rewarding. Here are some pointers to help you get started…

Ice Skating at Rockefeller Center – by Stuck in Customs

1. Be sensitive to the direction of light as this can increase contrast, shadows, textures and reflections. High levels of contrast can fool cameras into exposing the scene incorrectly, but shooters can easily overcome this by applying exposure compensation. Another trick is to bracket shots at different exposure values (exposing one for the highlights, one for the midtones and one for the shadows) and later merge them in a dedicated HDR program (such as Photomatix).

2. A fish eye or wide-angle lens (and focal length) is ideal for this genre as it enables photographers to frame the entire building within its environment. However sometimes your glass may not be able to encompass the whole scene, which is where the helpful panoramic format can come in handy. Many compacts now offer a specific Scene mode for stitching together several shots in camera, but the same effect can be achieved post-shoot with dedicated panoramic software such as; as Hugin or PTgui if you are shooting with a DSLR.

3. We are told it’s what’s on the inside that counts and sure enough architecture photography isn’t restricted to the facia of a building. It can be difficult to correctly white balance an interior setting, especially ones that are reliant on various forms of artificial lighting, so remember to compensate accordingly in the White Balance menu or take a reading from a grey card. Interior shots in older buildings tend to be more irksome because they traditionally feature small windows and doors – thus lack natural light. Try using a tripod and executing a long-exposure and remember you could always utilise an ND filter to stop highlights being blown out when shooting in the day. Alternatively you could use supplementary lighting, such as a diffused flash but be careful as this may rob the scene of its atmosphere and detail.

4. When the sun goes down a new form of architectural photographer can surface. To shoot a structure as a silhouette during sunset, position the architecture between yourself and the sun. Make sure the flash is deactivated and expose for the sky. If the foreground is too light set the exposure compensation to a negative value to darken it. This effect can produce particularly enigmatic results. Night shots can be very dramatic and atmospheric too, but remember to take them when there is still some light and colour left in the sky as this adds tone to the backdrop and help to illuminate details. As before get into a good position and set your camera on a tripod and wait for the dazzling display of urban lights from windows, street lights, signs – all of these in their rainbow of neon colours will add to the ambience. Use a wide aperture and long exposure, and if your camera is supported you’ll be able to employ a low ISO to ensure details aren’t depreciated by noise.

The Neo Monoliths of Chicago – by Stuck in Customs

5. Unlike other forms of photography, exciting architectural images can be produced in all weathers. A church on a clear day may strike the viewer as pleasant but maybe a bit bland, revisit it when there’s a storm brewing overhead or a mist rising from the damp earth and the results can be altogether more intriguing. By revisiting and shooting the same building in these various weather conditions, photographer’s can produce a neat portfolio of shots – maybe select the best three and you’ll have yourself an interest triptych.

6. Reflections add an extra dimension to architectural images and allow the photographer to create a canvas on which the building can be playfully distorted. Urban environments are littered with a multitude of reflective surfaces, so you’ll never have to look too far to practice, for example: windows, water features, puddles and wet streets, sunglasses, rivers and modern art.

Tervuren, Belgium – by fatboyke (Luc)

7. Research the reason why the architecture exists – you’ll be surprised how a little bit of background information can fuel a great deal of inspiration. Ask a guide to point out small yet interesting aspects that perhaps go unnoticed by the general public. Buildings of architectural merit usually include focal points so try cropping in close on these for frame-filling abstracts. Furthermore you may want to include repeated artefacts that are littered across the exterior, for example; intricate brickwork or chequer board windows. Use a telephoto lens to zoom in close and don’t forget a tripod to support those longer focal lengths.