White Table for Shadowless Lighting

A portable table for high-key photography in the field.

Many times we encounter great photographic opportunities in the field and can accomplish making some superb images of the subject in its habitat. (The mating stink bugs, below) Often however, it would be nice to capture images with greater clarity by the eliminating of ugly or distracting elements and improve the subject view by removing all the background.

I am often told by many that you can do all this in Photoshop or other post processing software. (Don’t worry, fix it in Photoshop.) While I know that to be true, why spend a lot of time in front of the computer when we can manage the technique in the field and in the camera?

 So, my suggestion is to use a translucent white acrylic plastic background sheet and create near shadowless, high-key lighting by using an electronic flash as backlight. Similar to the White Box technique, (See: Create shadowless macro backgrounds) this has been a common studio practice for many years. Now recreating this technique in the field sheds a new light on our subjects. (Pardon the pun.) Enter the White Table.

This simple tool is an open framework created of PVC plumbing pipe. My dimensions are simple, 12 inches on each side. And with the addition of a 12 inch square white acrylic plastic top, the table is complete. I do not cement the PVC joints so the legs readily come apart for ease of transport.

In use, above, the unit rests on the ground. A back light flash is positioned to fire upward through the plastic top to provide a blown-out background. A second flash on, or near, camera provides front light for the subject and the trigger for the back light flash.

Here is an example of the same mating stink bugs carefully moved to the White Table. This process provides a completely different view of the insects without background distractions. The photo is clean and this technique allows lighting for maximum detail.

A simple twist to this technique is to switch the white acrylic for a black sheet of the same material. This will allow the production of some images with nice, contrasting black backgrounds and interesting reflections. This works exceptionally well with hairy subjects like the tarantula, (below).

Copyright © 2016 Brian Loflin. All rights reserved.

Review: LAOWA 15mm F4.0 Wide Macro Lens

Nikon D800, 15mm F4.0 LAOWA Wide Macro lens.

SPECIFICATIONS

• Focal Length                        15mm
• Construction                        12 elements 9 groups
• Focus                                   Manual
• Aperture                               Manual
• Aperture, Maximum            4.0
• Aperture, Minimum            32
• Aperture                               14 blades
• Angle of view                      110⁰ 31’’ (Full Frame Camera)
  • 85⁰ 52” (APSC)
• Minimum Focus Distance   122mm (4.8 in) from sensor
• 4.7 mm (0.19 in) from front element
• Magnification                      1:1
• Shift                                     +/- 6mm
• Filter threads                       77mm
• Dimensions                          83.8 x 64.7mm (3.3 x 2.54 in)
• Weight                                 410 gm   (13 oz)

 OVERALL IMPRESSIONS

Upon reading of this new lens from Venus Optics I was skeptical of its performance. It always seems that when manufacturers try to put lots of capabilities into a single package, something ends up being a compromise.

Upon handling the product for the first time, I was impressed by the clean lines and smooth operation. The focus was smooth from minimum to infinity and required only a quarter of a turn of the barrel. The focus scale read in meters from 0.12m to Infinity. The barrel was also marked in Magnification units from 0.1:1 to 1:1. Upon focusing to minimum, the lens length increased only 1/4 inch, short for a macro lens. There was no turning of the barrel so filter orientation was not affected.

The aperture ring was marked from F4.0 to F32 and had no click stop detents. The separation of the aperture indices was very small and much care was required to accurately line up the index. The aperture ring was smooth and had no slippage.

It was interesting to note the lens had a Depth of Field Scale marked on the barrel, a feature seldom found on today’s electronic aperture lenses. The difference from max DoF to min DoF is a very small change of about 2mm rotation of the focus ring.

The lens is stated to be “Tilt-Shift” when in fact, the lens shifts up and down in the horizontal camera orientation only. No tilt is available. The shift moves +/- 6mm and is stopped by a locking lever and solid detents. The shift was somewhat stiff upon use. This should not be an issue on a tripod and may become smother with use.

NO SHIFT

 

FULL UPWARD SHIFT +6MM

Front filter threads are standard 77mm and with a lens of this wide angle thin filters must be used to prevent vignetting. The lens is supplied with a tulip shape lens hood and front and rear caps. When the lens hood is in place significant vignetting occurs in the full upward shift position of the lens on the Nikon D800 full frame sensor. This is said not to occur with a crop (APSc) sensor camera.

Nikon D800, 15mm F4.0 LAOWA Wide Macro lens-Vertical shift-Note lens hood vignette.

APERTURE

The first standard test was to measure exposure consistency along the full aperture range. The test was made with a standard photographic gray card in ideal, even illumination. Aperture priority mode and spot metering was used. The camera and gray card standard were tripod mounted. As previously stated the aperture markings were small and indexing was critical. Upon examination of resultant images it was discovered there was an inconsistency in exposure from wide open maximum aperture to minimum aperture.

Reflection density results are as follows:

•F4.0 = 58.7    • F5.6 = 58.9   • F8.0 = 57.8    •F11  =  54.2

•F16  =  52.6    • F22  = 48.6    •F32  = 41.1

 FOCUS

Focus was evaluated using a standard Adobe Lens Calibration chart. Aperture selected was F11. Under image magnification, there was slight falloff at the horizontal ends of the frame, yet little falloff at the top and bottom of the horizontal frame.

RESOLUTION

Lens resolution tests could not be conducted empirically at this time in the studio/lab. However, when distant images were examined at magnification there were significant failures in sharpness both at the small and large ends of the aperture scale. It was perceived that only F8 and F11 were truly sharp. F4 and F5.6 were soft and F22 and F32 were unacceptable.

 

MINIMUM FOCUS DISTANCE

As a close focusing wide angle lens, this model performed as expected. Knowing that F8.0 was sharpest, several test images were made with near foreground and distant subject detail. This is an example of that performance.

The real test was to examine images shot near the Minimum Focus Distance while looking for distant background detail. Most wide angle lenses can produce tremendous Depth of Field; super wide angle lenses even more so. This lens employs a two stage focus where the near and distant focus occurs in one movement of the optic and extreme close up focus occurs as a result of a simple lens extension, similar to the use of a very thin extension tube. Expectations in performance due to that construction configuration were great.

When it came to the actual test, two things were rapidly apparent: the lens hood was in the way and the subject was so close to the front glass that it was often in shadow of the lens.

The first image of the flower and its environment was made at a magnification of 0.8:1 as marked on the lens barrel. It works rather satisfactorily. However, remember, I felt that F8 was the only sharp aperture which resulted in not having the detail in the background that I would have liked.

The second image of the flower was shot at 1:1 as marked on the barrel. It is nice and the center point of focus is very sharp. (See the cropped inset below). Interestingly, some of the flower petals are actually touching the front glass element. The lens hood was removed to get the flower in position and managing appropriate light on the flower was extremely difficult. These conditions were disappointing.

COLOR REPRODUCTION

In this series of samples, the lens did not reproduce any significant chromatic aberration. In a couple of the building images a very slight amount of red fringing was noticeable in the highlights at 10:1 magnification. What small amount of fringing present was easily corrected in software.

DISTORTION

As one can imagine there can be distortion with this lens just like any other super wide angle optic. And there is. What’s interesting is that when used correctly and held square to the subject there is little vertical perspective distortion. (See the building image above) But move only a few degrees from square and that error is extremely noticeable. (Below)

Fortunately for this lens the shift movement helps correct the issue. It is disappointing not to find the shift movement in both axes. Even old PC lenses have the ability to turn the barrel 90 degrees so that shift is available in both axes. (See shifted images far above.)

When used with vertical structures close to the edges of the frame, barrel distortion becomes evident. However software fixes are available for this error.

SUMMARY

For the LAOWA 15mm F4.0 Wide Macro lens to perform perfectly under all conditions was an exaggeration at best. The lens did well at many of the tasks performed. As a super wide angle lens it did well when used properly except for the higher F stops. As a macro lens, the detail was good near the macro end of the scale. Again, poor resolution at the higher F stops resulted in a lack of great Depth of Field. This is a shortcoming of lenses in the macro range but since F16, F22 and F32 are not sharp with this lens, this characteristic is a disappointing shortfall. In the two scenarios the use of the lens hood was a problem; when the lens was shifted upward (or downward) and when used at the close focusing distances.

For the casual shooter this can prove to be a useful lens, especially for the price. Canon and Nikon lenses are generally four times the price. And, to get the most from this optic, its shortcomings must be known and used in a manner that will minimize these shortfalls. When used properly and within known limitations, this lens can perform rather well.

For more specialized photographers however, the overall capabilities do not meet expectations. Both Canon and Nikon market top-of-the line tilt-shift lenses in focal length from wide angle to short telephoto. These lenses perform flawless at the tasks for which they were designed. These manufacturers also offer macro lenses in several focal lengths that produce macro images at 1:1 of the very highest caliber. If you need the best in these areas, you must pay the price.

Copyright © 2016. All rights reserved.

NEW: MacroQuest –coming soon!

 

MacroQuest is an intensive photographic expedition into the tiny natural world that surrounds us. During the Quest each photographer works to discover as many of the small natural subjects that can be found in the study area and to document those subjects using high quality, close-up and macro photographic techniques. MacroQuest is not a competition per se, but participants all work hard to build as large a body of work as possible during the period.

MacroQuest will explore all areas of the biotic environment including land, air and aquatic realms. The Quest targets may include all forms of plant, animal and mineral specimens. The goal is to discover as many unique species from as many orders and families as possible.

MacroQuest will be held in designated geographical areas of rich biodiversity that include as many habitat types as possible and that are not restricted to public access. Occasionally, MacroQuest may be held on other private lands. The goal always is to capture biodiversity.

Equally important to MacroQuest is the informed identification of the subject of every photographic image and the inclusion of the location and habitat where found. Therefore, an image data form will be completed for each image and will be shared at the end of the quest period. It is requested that representative images from every participant be used in the promotion of MacroQuest and of biodiversity itself. All photographic images shall remain the personal property of the image maker and copyright to those images will remain with the maker.

Watch here for upcoming announcements. For more information, please contact: bkloflin@austin.rr.com.

Copyright © 2016 Brian K. Loflin. All rights reserved.

Which lens do you use?

 

Nikon D800, Nikkor 105 mm F 2.8 lens.

We are told that the key to making a good composition is to pick the “right” lens and decide where to place it and the camera in relation to the subject.

It quite true that you can fill the frame with a portrait and make the head size the same dimension in the frame regardless of the lens focal length used. Even though this is true, there may be a better choice for selecting one focal length over another. Let’s evaluate a few images all made at the same spot:

   

This image on the left is made with a 20mm Wide Angle lens. It is quite obvious the face is distorted by the wide angle. In addition, the lens was just over one foot from this lady’s nose- quite uncomfortable for the subject.

This image on the right is made with a “portrait” lens, a fast 60mm F2.8 prime. It still is a bit wide and the lens to subject distance is still quite uncomfortable. With these two lenses the background is more defined that desirable.

    

The left image (above) is made with a fast 85 mm, F1.8 prime. It is beginning to look better. There is more comfort with the subject. Yet, the background is still somewhat more defined than desired.

The image on the right is a prime 105 mm F 2.8 lens. The working distance is very comfortable, the background becoming soft and there is little distortion of the subject’s face.

The next pair of images (below) are made with focal lengths in the telephoto range. They look much better than those above.

   
Camera: Nikon D800. Nikkor lenses: 20mm F2.8, 60mm F2.8, 85mm F1.8, 135mm F2.8, and 70-200 F2.8 zoom.

The left image is a 135mm F2.8 prime and the right, a 200mm F2.8 zoom . Both of these lenses produced good frame-filling head shots with pleasing facial features and nicely softened backgrounds. All images are made on a full frame Nikon D800 digital SLR at an aperture of F3.5.

So, in my book you can’t beat the image quality and feeling with the two telephoto lenses. For years and years, the choice for portraits on full frame cameras has been the 105 mm lens, regardless of whether shooting on film or in digital. We can now understand why.

So, the concept of a “portrait” lens for digital is a little misleading. The 50mm F1.4 is and always has been a great choice for editorial portraiture. This is because of the ability to better manage the Depth of Field and to tell a story, not for its focal length. For many this lens is simply just too short to use for pleasing head shots.

However, with a full frame 50mm lens on a crop sensor camera, the 50mm acts much more like a 75mm in its angle of view and  because you may be a bit further back.

Still it’s hard to beat the longer lenses. The advantages are many. You may fill the frame further from the subject, reducing distortion and improving a soft bokeh and shallow Depth of Field in the background. The narrow angle of view allows a small  “slice of life” to be made, eliminating many background distractions. Additionally, if you are shooting with lights or lighting modifiers, you have more working room if further back.

Copyright © 2016 Brian Loflin. All rights reserved.

 

 

 

 

 

 

 

Manage the Background – Part three.

I previously discussed managing the background through Depth of Field and through contrasting tone values. This last discussion revolves around the third method of setting off the subject, using contrasting or complimentary colors.

To understand this color concept better, we need to review the theory revealed in the Color Chart. For purposes of discussion in digital photographic terms, we use the RGB (Red, Green, Blue) color chart (below), an additive color scheme.

In the RGB color chart (above) we see the photographic Primary Colors of Red, Green and Blue labeled in white. You may notice they are spaced evenly in thirds, or 120 degrees, around the wheel. Across the wheel from each of the the primary colors we see the Secondary Colors of Magenta, Cyan and Yellow. These secondary colors are actually made up of equal parts of the two adjacent primary colors.

Colors that are opposite each other on the chart have maximum color contrast, and are called complimentary colors. Two colors commonly found in nature are blue and yellow, a maximum color contrast of two complimentary colors.

In this sunflower photo the yellow flower contrasts perfectly in color with the blue background. This is because the yellow is exactly opposite the blue on the color chart. That makes them complimentary colors and one of the most visible of color contrasts.

Nikon D2Xs, 200mm F4.0 Micro Nikkor, daylight.

For this cone flower (above) we have the  secondary color of magenta petals against the primary green background. Based upon our understanding of the color wheel these colors are still complimentary, thus of maximum color contrast.

Nikon D2Xs, 200mm F4.0 Micro Nikkor, daylight.

However, in the Indian blanket flower photo (above) the reds and oranges are not complementary to the green background. This is because they are not opposite on the color wheel.They are in fact, analogous, meaning adjacent on the wheel. Analagous colors work well together and create a harmonious color scheme. Here, the yellow tips to the flower petals separate it from the background primarily by contrasting tones rather than color.

However , the Shinia moth near the flower  center, a symbiotic insect to the Indian blanket, does not contrast well with the flower. This is actually to the moth’s benefit- a color mimicry trait that protects this moth from predators.

So, what ever the method you can use to separate your subject from the background, it’s a good tool to help attract the viewer’s attention to the subject. If more than one technique can be used in a single image, that’s even better.

Good photographic composition begins with a visual preview of the scene. Do everything you can to find and use as many elements of good design to give your image as much impact as you can within the camera. That will make the task of post processing must easier and allow your images leave the viewer with a lasting impression.

Copyright © 2016 Brian Loflin. All rights reserved.

Manage the Background – Part two

I have often discussed the importance of assuring the subject stands out in the frame. To do this you must manage the background.

Previously, I discussed the first method in which you can separate the subject from the background by using a very small Depth of Field. Here I will talk about using contrasting tone values.

Nikon D800, 105mm F2.8 Micro Nikkor lens, daylight.

In the image of the flowering seed head of Bushy bluestem grass, the highlight and mid-tone values of the plant structure contrast very well with the dark, mottled tones of the background. This allows even the finest detail to be visualized quite well. Remember, here I talk about tone values- not colors. This means changes in reflectance from dark to light. Even though monochromatic in characteristic, this subject is very well defined.

Nikon D800, 200mm F4.0 Micro Nikkor, sun, SB-910 fill flash. Three frame HDR image.

A more colorful Passion flower really snaps out against the darkest of backgrounds. In this case some of the flower’s filamentous petals and the leaves themselves make up the background.

I am frequently asked how do you make the background dark. The answer is simple, don’t put light on it. In other words, find or make the background about two stops darker that the mid-tone exposure value. Find a Point of View that yields a nice underexposed background. Or conversely, shade the brighter background with your hand, body or a piece of cardboard or opaque reflector. If you make a shadow fall behind the subject, that’s it!

Nikon D800, 105mm F2.8 Micro Nikkor. Two SB-910 Speedlight flashes.

The polar opposite of dark backgrounds is to make a high key, or very light background. In this case, the high key background is useful to better define the edges of medium-to-dark subjects as in the mating stink bugs above. Many times natural lighter surfaces or backgrounds may be found. When that is not possible, placing a light material or lighted surface behind the subject works well. In the case of the stink bugs, the subjects were placed on a sheet of opal acrylic plastic that was illuminated from behind with a flash (speedlight). An additional speedlight provided front illumination from above. With the capabilities found in today’s flashes, it is relatively simple to vary the TTL (Through the Lens) power ratio of each flash independently, producing the desired tone values of the subject and of the background separately.

Regardless of your choice-light or dark- be sure to manage the distractions to produce a subject that pops!

Copyright © 2016 Brian Loflin. All rights reserved.

 

 

 

 

 

 

 

Showoff your Subject- Manage the Background

Northern Cardinal female, Nikon D800, Nikkor 80-200 F2.8 lens, 1.7x teleconverter.

 

To achieve the very best from every photographic composition it is very important to assure the subject stands out in the frame. To do this you must manage the background.

There are three basic ways to manage the background: Separate the subject from the background by using a very small Depth of Field; Use contrasting tone values; and Use complementary colors. The more of these effects that are used in a photograph, the more successful that composition becomes.

The first method is to set off or separate the subject from the background by muting all background distractions by using a minimum amount of Depth of Field  (or depth of focus).  To do this effectively first focus carefully on the subject and use a small F number aperture. The small F numbers provide a very small amount of the scene, both in front of and behind the point of focus that is in acceptable focus.

It is not reasonable to simply use the smallest F number provided by the lens. It is important to have enough DoF to cover the subject in its entirety. Larger subjects require a bit larger DoF.

Here is a comparison. The first image below is of the branch where the cardinal was perched. It was made with a lens at 340mm and at F29. The second image was made at F4.8. The comparison is quite evident. It is also important to remember that the DoF gets smaller as the lens focal length gets longer.

Deep and distracting background above. Few distractions and smooth, pastel background below.

In the next post we will review the second technique, use of contrasting tone values.

Copyright © 2016 Brian Loflin. All rights reserved.