Tag Archives: photography

Increase Depth of Field with Focus Stacking

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Combination image of cactus with spines. Deep focus stack with 28 images, front to back, (left) and single image from center of stack (right). Nikon D800, 105 mm F2.8 Micro Nikkor, SB 910 flash and circular diffuser.

There are many times when a single image, even at the smallest aperture simply will not produce enough depth of field (DoF) to render the image sharply. This is regardless of the lens quality, camera or technique. The image above is a demonstration from a recent Nature and Macro Photography Workshop.

We have learned that DoF is dependent primarily on Aperture. (The bigger the aperture number; the bigger the DoF.) But DoF is also dependent upon Subject Distance, and lens Focal Length. As we get closer to the image and increase our lens focal length in macro photography, the total measured distance of the DoF gets smaller. Working in close-up am macro photography we are working against ourselves when it comes to DoF. Therefore, we need to improve upon this fault.

To extend the DoF we can now rely upon computer blending of several images into one with greatly extended DoF. Each image is focused at a different distance from the lens. An additional benefit of this technique is the use of a middle range, somewhat sharper aperture. When blended in computer software, part of the resultant image uses near focus detail, part uses mid-focus detail and another uses far focus detail, and so on. Often, as many as 10 or more sequential images are “stacked” and blended into one.

This blending process can include the use of multiple layers in Photoshop or free software called CombineZ or Zyrene Stacker. However, the most powerful software and today’s industry standard is Helicon Focus. The current version is 6.3.7 and its cost ranges from $30 to $200 depending on length of subscription service and number of computers licensed.

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Nikon D2Xs, 50 mm flat field EL Nikkor lens on bellows, two SB-800 flashes, tripod. Image magnification in camera: 1.6X.

In this image (above) of the head of a bee 53 individual images with a different point of focus from the antennae to the rear of the head were made. Each image was spaced 0.005 inch from one another from the front to the back. These multiple images spanned the overall distance of o.265 inch, (or about a quarter of an inch).

So as you can see, focus stacking can help produce a little more DoF or a great amount as in the bee. It is also useful in landscape photography to produce foreground, midground and background in equally sharp focus.

Copyright © 2015 Brian Loflin. All rights reserved.

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The importance of managing light.

Needless to say, light is of paramount importance in photography. The word photography is translated from the Greek as “writing with light.” Without light, photography would be most difficult indeed.

Light does a lot for us in our image making. It allows making the very basic exposure itself. It provides shape, form, texture and dimension. The management of light helps us to render our subject with the most emphasis where desired. We’ll look at these ideas in a moment.

To further understand light we need to remember that it has several vastly important characteristics:

  • Light has intensity, or the characteristic of brightness. That characteristic requires us to produce a proper exposure using our camera meter, setting shutter speed aperture and ISO.
  • Light has color, the inherent wave length or color temperature of the light as it illuminates the subject. This color requires us to manage White Balance.
  • Light has direction, the angle that it strikes the subject. Front light, side light and backlight all have important uses in rendering our subject with the best results, and finally,
  • Light has quality. This characteristic is perhaps one of the most important. Light may be very soft and pleasing or hard, high contrast and very unflattering. Of all the light characteristics, the management of this quality of light requires our utmost effort.

Of all the light characteristics, the camera can manage intensity and color, but we need to be careful to manage light’s quality and direction to achieve the optimum reproduction of our subject. Unfortunately, I see a lack of lighting management in these two areas quite frequently. Let’s look at some ideas.

First let’s understand that light in itself helps us produce a shape but shadow helps us create form and dimension. We really need to manage both in the creation of quality images. I know that shadows are often bad; they may block up detail and detract from the image. And, often we appreciate images that are virtually shadow-free. I have written a piece for a shadow-less light application for small close-up and macro subjects. You may read it here.

Lighting direction is important to use in making our images. Front light gives us shape and form. Light from over our camera or shoulder can reveal a lot about our subject. As light wraps around the subject features, the variations in intensity, or falloff, tells us a lot about the features of the subject. But this comes with a price. Front light is often flat, that is, lacking in contrast. This low contrast lighting fails to give adequate details of the subject surface.

Therefore, lighting direction is most important when attempting to bring out the most subject details. Three lighting techniques are important to learn: Axial (Front), Side and Back.

With axial lighting the light source is at the lens or close to it and illuminates the subject directly on the front surface. (See Diagram Below) The image of the Overcup oak acorns below is lit with an off-camera Speedlight flash in a small softbox right up against the lens. While it produces a nice image, it is somewhat flat and lacks the contrast to illustrate the detail at its best.

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Side light, corrects this failure of front light. In fact, to visually achieve maximum surface texture, extreme side light is the answer. Texture is that all-important tactile quality of what the subject feels like; as in does it feel smooth or rough.

The image below is lit with the same Speedlight and softbox to the far right of the subject. This image produces maximum detail and texture of the acorn and the surface of the caps.

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Backlight, while sometimes difficult to work with because of little definition to front details, provide a maximum understanding of shape, a two-dimensional quality. Backlight can separate the subject from the background and produce a striking edge-light or “halo” around our subject for maximum definition. In the image below, the single Speedlight and softbox is placed behind the acorns. The image illustrates maximum shape and edge detail, but is lacking in front surface detail due to insufficient light from the single source.

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Now, as it turns out, we may use more than only one style of lighting direction; a mixture is frequently best. Here the lighting is predominant back light with a front fill card. This image provides more information, better illustrating the acorns and the detail of the caps.

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In addition to direction, lighting quality is vastly important as well. Small point light sources create hard, high contrast light. A point light source is very small in relation to the subject and directional. The light from our sun is actually small (you can cover the sun with your thumb at noon) and directional, creating lots of unflattering, dark shadows.

On the other hand, large and broad light sources are much softer, especially when close to the subject. An overcast sky is a perfect example of a large light source; the clouds themselves act as the large source of light. Let’s look at some specific examples.

In the first two images below the light is a single off-camera Speedlight flash both at the same distance (2 ft.) from the subject. In the left image the flash is unmodified and the right uses an 18 inch diffuser in front of the Speedlight. The first has considerable more specular reflections and sharper (harder) shadows; the next with the larger light source is more diffused, both in the highlights and shadows. The larger the light source, the softer the light and less contrast.

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The quality of the light is also subject to the size of the light source relative to the subject as a function of its distance from the subject. In the four examples immediately below, the light source is the same exact fixture — an eight-inch softbox on a Speedlight. In the top examples the light source is six feet from the subject. In the lower images the light is only one foot away.

When the light source is at a distance it seems small as below, shadows are at their maximum and spectral highlights are small and hard. Look at the detail of the reflection from the light source. (Closeup second below).

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When the light source is large (closer) as below, shadows are at their minimum and spectral highlights are large and soft. (See the next closeup.)

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The images below are shot with a very soft lighting technique making use of a large light, close to the subject with reflectors and diffusers, resulting in less contrast, less shadows and more diffused highlights. This is a technique used frequently for shadow-less lighting with diffused specular highlights, like shiny metal or glass objects.

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So after all that, let’s take a look at some examples where direction and quality play an important role in making or breaking an image. The images below are of the skull of a white-tailed deer. This animal was probably killed by being hit by a car resulting in the crushed skull as shown here.

The first image is taken with the light suggested for everything. Near axial, front lighting with a softbox on an off-camera Speedlight flash. The enlarged detail shows the image is well lit and exposed and illustrates the subject and the trauma.

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The image below however, used side light with the same Speedlight and softbox. This image illustrates more detail than the first as the sidelight creates more texture, giving more definition to the bone and its structures. This is clearly visible in the enlarged detail.

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Copyright © 2015 Brian Loflin. All rights reserved.

Sights and colors of Autum

The last week of September, I took a short trip to Rocky Mountain National Park in Colorado. In addition to getting some much-needed “away time”, I wanted to photograph Elk in the rut and the colorful Aspens at their peak. I was surprised to discover that I arrived at the best week- for both!

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 Nikon D-800, 600mm F4.0 Nikkor lens, tripod.

The bulls and their hormones were very active and good images were easily found. The color was a bit splotchy as there was a previous beetle kill in the the pines. But a little perseverance paid off with some nice color.

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Nikon D-800, 80-200 mm zoom Nikkor lens, tripod.

Copyright © 2014 Brian Loflin. All rights reserved.

Don’t miss: Two new South Texas bird photography workshops

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South Texas Bird Photography Workshop •Laguna Seca Ranch Edinburg, Texas
• October 23-26, 2014
• February 27-March 1-2015

This instructional, hands-on bird photography workshop is located in the heart of the South Texas flyway. The October workshop features a half-day of hands-on instruction and a day and two and a half days of shooting (or a day and a half in February ) in some of the best South Texas birding habitat available where neotropical South Texas varieties abound.

The workshop will be held at the Laguna Seca Ranch north of Edinburg, Texas in the heart of the lush Rio Grande Valley. The facilities of the 700-acre ranch are purpose-designed for photography and preserved with all native species. It features four constant-level ponds, each with permanent photography blinds oriented for the best use of light. A fifth blind is set up specifically for raptors.

Each location has been hand-crafted to provide the most outstanding bird photography opportunities. With nearly eighty species found on the property, Laguna Seca Ranch clearly offers a uniquely outstanding South Texas bird photography adventure! Many photographers have added numerous birds to their species life list while at the workshop. Read the website for their testimonials.

For more information, see: http://www.thenatureconnection.com/SoTxBirdPhotoWS.html

June Macro Photo Workshop

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Ten avid participants from as far away as Minnesota discovered great surprises as they developed new skills in the exciting small world of macro photography. The workshop was held in the heart of the Texas Hill Country at the historic Mo Ranch Conference Center in Hunt. Everyone expanded their understanding and skills through classroom instruction, and intensive, hands-on field and lab photography sessions.

Participants said their macro images are much better than any they would have taken before this instruction.  Most participants were also in for a big surprise as they learned precisely how little DOF their macro lens has. All appreciated learning how to use flash to improve their work and learning to use Live View for better focusing on tiny objects.

Of special interest was the use of a macro focusing rail, focus stacking, flash for additional depth of field and techniques for mitigating wind.

Mo Ranch was a really great place to hold the workshop–very relaxing and lots of nature to photograph. Participants would definitely recommend this workshop to others.

Several of the images from the workshop are shown below:

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Photos:© Melody Lytle, Rose Epps, Steve Houston.

See more participants small world images on Facebook at https://www.facebook.com/pages/Brian-Loflin-Macro-Workshop/469018396566911

Copyright © 2014 Brian K. Loflin. All rights reserved.

Move the Mole Hill, not the Mountain

In macro photography we are supplied with a variety of components for fine-tuning focus. This equipment includes focus slider rails and built-in sliders as part of a bellows. All of these devices facilitate changes in focus by moving the camera closer or more distant from the subject.

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All of these components work quite well; some better than others. A well-made slider (above) can provide infinite adjustments in focus with extremely small changes in distance.  These are ideal for gross specimens or single shot macro images.

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Bee head. 53 images stacked in Helicon Focus. Nikon D2Xs, 50 mm flat field EL Nikkor lens on bellows, two SB-800 flashes, tripod. Image magnification in camera: 1.6X.

However, when enhanced depth of field of tiny subjects is required through focus stacking, moving the camera may not be the most ideal method of changing point of focus. With very small insects like the bee above for instance, many exposures–perhaps 50 or more– must be produced over a distance of less than one centimeter.

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Several problems are presented. First, the mass of the camera, bellows, and lens assembly is great. Moving it smoothly and accurately may not be possible. Second, the focusing rack and pinion may have coarse threads, not suitable of minute adjustments.  Further, the camera, bellows and lens combination when moved is subject to unwanted vibrations. The answer therefore, is to move the subject, leaving the camera solidly stationary.

Macro subjects like those encountered for focus stacking are most frequently tiny and present no above mentioned problems. They are small, lightweight and can be easily and smoothly moved. And making repeated movements at uniform dimensions is practical. All this suggests that moving the subject instead of the camera is an ideal solution.

In my photography, I use two devices. For single shot macro I have converted an Olympus microscope stage for an X-Y-Z motion platform in the image below. It has a movement of 3 inches in left-right and fore-aft directions and a vertical movement of just under 1 inch. In addition, it has a 2 x 3 inch hole for sub stage illumination. All movement controls are under the stage so they are perfectly out of the way.

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For focus stacking I use a single-axis micrometer linear positioning stage. Movements are possible along the lens axis for focus stacking in uniform increments as small as 0.001 inch. The movement for this stage is only one inch, but that is more than adequate for most focus stacking tasks. To center and align the subject, I use the gear head on my heavy duty Gitzo tripod. As illustrated in the photograph below, everything is locked down tight. Consistent, vibration-free images are possible with this set-up.

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For the ultimate in focus stacking, a motorized linear positioner like StackShot® by Cognisys makes life easy. The price is affordable if a lot of focus stacking photography is required. Even with the StackShot it still makes perfect sense to move the mole hill not the mountain!

© 2013 Brian Loflin. All rights reserved.

Texas photo workshops seem worlds apart

Happy New Year! To start the New Year out right, I will lead a series of nature photography workshops in 2013. While all are in Texas, the subject matter seems worlds apart. They range from an African wildlife photography workshop at
Fossil Rim Wildlife Center and another wild bird photography workshop in far South Texas. Let’s start in order.

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The first workshop will be held on February 22-24 on the Laguna Seca Ranch in far south Texas only a few miles from Edinburg and the Mexican border. This ranch is a well established for bird photography with permanent blinds and water features. The timing of this workshop will allow the participants to capture images of south Texas and northern Mexico specialties, as well as migrant species. The details of this most economical workshop are found here: http://www.thenatureconnection.com/SoTxBirdPhotoWS.html .

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The next workshops feature Africa in Texas at the Fossil Rim Wildlife Center near Glen Rose, Texas. Four workshops will be featured in April, June, September and October on the 1,900 acre facility. One- and two-day workshops are offered, with the two-day workshop featuring lodging overnight at Safari Camp in the heart of the center’s wildlife preserve. For more information visit http://www.fossilrim.org/workshops.php.

All workshops feature copious hands-on instruction, plenty of great subjects and are limited in participant numbers to assure lots of individual attention. To download a flier for either of the workshops click on the link below:
South Texas Bird Photography Workshop:     RGV Bird Photography
Fossil Rim Wildlife Photography Workshop: FR WildlifePhotoWS

© 2013 Brian Loflin. All Rights reserved.