Tag Archives: Bellows

Nature & Macro in the Texas Hill Country

Join me at Mo Ranch in the very heart of the magical Texas Hill Country for a three-day nature and macro photography workshop geared to shooting in field settings and indoors. Dates are Friday-Sunday, September 18-20, 2015.

This workshop will be packed with hands-on instruction to help you grow your photographic abilities with new found skills, techniques and proficiency. Two nights lodging and six meals provided.

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The historic, 500 acre Mo Ranch is located in a beautiful setting on the North Fork of the Guadalupe River. Here, habitats include: aquatic, riparian areas, grasslands, oak-juniper woodlands, and limestone hills. We will make use of all of them.

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The workshop will feature classroom instruction, hands-on learning, and computer demonstrations  with native flora and fauna of the area. A computer lab is available for all participants for processing images. The workshop will cover many subjects including discussions on:

•    Equipment for getting close   •    Wide Angle Close-Ups
•    Backgrounds   •    Tools to make macro work easier
•    Lighting with Flash & High Speed Flash
•    High Key and White Box
     •    Macro Panorama
•    Extreme Macro   •    Focus Stacking

For more information, visit my website: Nature-Macro Workshop 
Or, E-mail me direct: bkloflin@austin.rr.com  .

Copyright © 2015 Brian K Loflin. All rights reserved. 

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Small, smaller, smallest: Now nearly complete

This is an update of the first installment from

Commonly, when we think of close up images we envision filling the frame with subjects the size of a butterfly. When we think of macro, that subject size becomes smaller by a factor of five or so. That might be a small beetle or maybe a fly. There is a vast world that is much smaller that is worthy of our photography prowess. That is the world of ultra macro or indeed micro photography.

There are many tools used for life-sized images. The macro lens, extension tubes, bellows attachment and even microscopes. Each has its advantages,  disadvantages and limitations. Some of the major considerations when doing image capture at magnifications vastly greater than life-size include, image resolution, focus, depth of field, lighting and vibrations to name a few. The micro world is a challenging one indeed.

Extreme magnification image making calls for a stable specimen and camera platform, precise and uniform movements in focus and absolutely uniform, clean lighting. In order to accomplish this a bellows and true macro lens is used with a micrometer specimen stage and electronic flash. All this apparatus may create a big problem: movement through vibrations. This really reduces image resolution.

To overcome these problems, I am have assembled a specialized piece of  equipment to enable the precision required on the lab bench in a controlled environment. This is my work as is nearly completed. The idea is not new, but getting all the pieces together has been interesting. Macro work in the field requires a completely different set of equipment.

This micro set up is designed for stability combined with versatility and for use from magnifications of 1:1 or life-size on the sensor with a 55 mm macro lens to magnifications of up to to 40:1 with a true microscope lens on the bellows. It looks like this:

_BKL2340

For smaller magnifications near life-size, the Nikon D-SLR camera is equipped with a 55 mm Micro Nikkor lens. Camera movement is facilitated by a geared linear positioner with provisions for a stepper motor, a long Arca-style plate on the positioner table with small ball head. All components are uniformly equipped with Arca-style QR clamps or plates. For greater magnifications, the camera is fitted with a Nikon PB-4 bellows with focusing rail. Various lenses may be used from the 55 mm Micro Nikkor to the 19 mm Macro Nikkor as seen in the two images below:

_BKL2369-A_2

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Subject positioning  is possible in all four X, Y, Z and Theta planes. A cannibalized AO microscope stand provides coarse and fine movement in the vertical direction. A linear motion micrometer stage provides precise movement in X and Y directions and a rotation stage assembly with micrometer provides precise rotation. The specimen is held by an articulating holder mounted on the linear stage. (See Variable macro specimen holder) This holder will facilitate the use of pinned insects in addition to other larger materials fastened to the stage itself.

All this assembly is mounted together on a platform to reduce independent vibrations. The weight is substantial, providing additional aid in mitigating vibrations. The current mounting base is dimensional lumber, future refinements include an all-metal base and the addition of a stepper motor for automating focus stacking.

The design  is clean and compact and without bulky tripods and other equipment in the way. The Arca-style rails provide unobstructed mounting for  SB-800 or SB-910 electronic flash on a Wimberley articulated macro arm.

High magnification imaging viewing is provided via camera live view or tethered shooting on a laptop.

With this equipment arrangement deep focus stacks at high magnifications are possible in increments of 0.001 inch and at extremely high resolution with mirror lock-up and hands-free electronic remote cable release.

Small, smaller, smallest: A work in progress

Commonly, when we think of close up images we envision filling the frame with subjects the size of a butterfly. When we think of macro, that subject size becomes smaller by a factor of five or so. That might be a small beetle or maybe a fly. There is a vast world that is much smaller that is worthy of our photography prowess. That is the world of ultra macro or indeed micro photography.

There are many tools used for life-sized images. The macro lens, extension tubes, bellows attachment and even microscopes. Each has its advantages,  disadvantages and limitations. Some of the major considerations when doing image capture at magnifications vastly greater than life-size include, image resolution, focus, depth of field, lighting and vibrations to name a few. The micro world is a challenging one indeed.

DA01-bloflin0312

The above image is the head of a bee. It is magnified about 1.6 times on the sensor. This is not a very great magnification, but in order to capture sufficient depth of field in this image 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.

Image making like this calls for a stable specimen and camera platform, precise and uniform movements in focus and absolutely uniform, clean lighting. In order to accomplish this a bellows and true macro lens was used with a micrometer specimen stage and electronic flash. All this apparatus may create a big problem: movement through vibrations. This really reduces image resolution.

To overcome the problems, I am assembling a specialized piece of equipment to enable the precision required. This is my work in process. The idea is not new, per se, but getting all the pieces together has been interesting. It looks like this:

Micro-6098-Sm

This micro set up is designed for versatility and for use from magnifications of 1:1 or life-size on the sensor with a 55 mm macro lens to magnifications of close to 40:1 with a true microscope lens on the bellows.

Camera movement is facilitated by a geared linear positioner with provisions for a stepper motor, an Arca-style plate on the positioner table and the focusing rail of the Nikon PB-4 bellows.

Subject positioning  is possible in all three X, Y, and Z planes. A cannibalized AO microscope stand provides coarse and fine movement in the vertical direction. A linear motion micrometer stage provides movement in X and Y directions. The specimen is held by an articulating holder mounted on the linear stage. (See Variable macro specimen holder) This holder will facilitate the use of pinned insects in addition to other larger materials fastened to the stage itself.

All this assembly is mounted together on a platform to reduce independent vibrations. The weight is substantial, providing additional aid in mitigating vibrations. While the current prototype mounting base is dimensional lumber, future refinements include an all-metal positioning table and the addition of a stepper motor for automating focus stacking.

The clean design without bulky tripods and other equipment in the way allows the use of SB-800 or SB-910 electronic flash on articulated arms in a unobstructed manner.

A future post will visit images made in much greater magnifications. Improvements to image resolution will be measured and discussed. Stay tuned!

Variable macro specimen holder

Many times when photographing tiny specimens with great magnification, the best subject angle is difficult to obtain. When attempting to make a change, the images change is too great or still not the best view.

This simple subject holder provides good stability and almost infinite angles to work with. Several microscope stages are commercially available from suppliers such as BioQuip of California. However, the construction of this holder is easy and much less expensive with a only couple of dollars of common hardware store parts.

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Variable specimen holder-three views.

The holder is made with a 3/8 x 1/2 x 1 inch steel spacer sleeve, a 3/8 inch cap nut, a magnet and a bit of wire and cork. The magnet is shaped to create a friction fit when recessed a bit into the sleeve so that when the cap nut is inserted into the sleeve it will hold the nut securely in place but provide infinite rotary motion. To finish off the project a short length of wire for a handle is inserted into a hole drilled on the face of the nut and, along with the piece of cork, is epoxied into the nut. Lastly, a machine screw is epoxied into the lower end of the sleeve to use as an anchor to the macro stage.

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A- 3/8 inch steel sleeve; B- 3/8 inch cap nut; C- cork disc; D- piece of stiff wire.

Copyright © 2014 Brian Loflin. All rights reserved.

Where’s the aperture ring?

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Modern Nikkor lenses: 60mm F2.8 Micro Nikkor with manual aperture ring (left) and 18-200mm F3.5 – 5.6 VR zoom. Notice the absence of the aperture ring on the zoom. Image made with Nikon D2Xs and 200 mm F4.0 Micro Nikkor and flash.

With today’s electronic technology-driven cameras, many of our exposure controls are as convenient as a finger push on the camera body. And with experience, we never have to remove our eye from the viewfinder.

The shutter speed and aperture selection is controlled electronically through the selector wheel on the camera body. However, in natural science photography there are cases where electronic aperture selection is not possible because the electronic connections between the lens and the camera body are not workable.

Do I mean the camera malfunctions? No, not at all. What I mean is that, through the addition of some components between the camera body and lens, the electronic circuitry is interrupted. This happens with some extension tubes and bellows (below), as well as microscope adapters. This is not uncommon, nor does it really pose a problem when you are aware of what’s really happening.

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So without electronic aperture selection, apertures need to be selected manually with the aperture selector ring and the exposures made in Aperture Priority (or Av) shooting mode. The camera will measure the light that falls on the internal metering sensor and set the shutter speed appropriately.

There may be one problem, however. Some lenses do not have a manual aperture selection ring on the lens barrel. Nikon calls these lenses “G” lenses. We fondly call them “gelded” lenses. Many Canon lenses are without the ring as well. So, it ends up that these are not really appropriate for this type of photography. We need to look for those lenses with aperture rings available. There a number of current Nikkor optics with the aperture ring. The 60 mm, 105 mm, and 200 mm macro lenses still have the aperture selector ring. Also the series of manual Nikkor lenses from 20 mm to 105 mm also retain the aperture selector ring.

Fortunately, under the correct circumstances, many older lenses (Canon and Nikon, too) may be used on modern D-SLR cameras. These lenses frequently have the aperture selector ring. And with adapters, Nikkor lenses may be used on Canon EOS series camera bodies. This is a nice option due to the great selection available  of Nikkor optics.

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.

Macro platform-0964-Sm

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.

Extreme Macro Depth of Field

Again and again, we have learned that there are several occasions where a single, yet well-executed, digital image may not capture the expected results. Most commonly we see High Dynamic Range images from a series of bracketed frames
providing greater tone values of a scene than possible with a single exposure.

Many pictorial images have a very wide Depth of Field range that somewhat limits the capability to capture front-to-back sharpness in a traditional digital image regardless of the aperture selected. We have also learned this DoF is dependent primarily on Aperture, then on Subject Distance, and lens Focal Length. As we get closer to the image in macro photography, the total measured distance of the DoF gets smaller. Therefore, we need to improve upon this fault.

Like in HDR, with the Extreme Depth of Field process we rely upon the blending of several images into one with greatly extended DoF. Each image is focused at a different distance from the lens. 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 a free software called CombineZ. However, the most powerful software and today’s industry standard is Helicon Focus. The current version is 5.2.16 and its cost ranges from $30 to $200 depending on length of subscription service and number of computers licensed.

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 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.

The screen shot above is from Helicon Focus. It illustrates the blending of these images into the resultant single Extreme Depth of Field image of the bee. The two images below demonstrate the difference in focus from one of the more front images to one of the most rear images. As illustrated, the DoF of any of the images is nil at this magnification.

A most helpful tool for capturing the many individual images required is a focus slider, a tripod mounted, rail-like device that facilitates the movement of the camera backward and forward at very small increments, thus changing the point of focus. (Moving the camera for focus is done as opposed to rotating the lens barrel normally which would change magnification at this scale.)

In my lab, the camera remains stationary and solidly mounted on a heavy tripod. I use a micrometer stage to move the specimen which provides infinite, yet measured travel over a distance of just more than one inch in measured intervals of 0.001 inch. This process proves most ideal when dealing with insects and other tiny specimens. This equipment set-up with a variety of macro lenses is capable of producing images up to 40X magnification. (See image below.)

Camera and bellows with focusing rail mounted on heavy tripod, specimen on micrometer stage, twin SB-800 on articulating arms with ball heads, auxiliary battery power for Speedlights, electronic cable release.

As in other high-magnification applications, any movement of the camera or subject is most detrimental to image quality. Therefore, solid mounting is paramount. Bolt everything down on solid, vibration-free surfaces. The heavier, the better. In addition, use an electronic cable release and mirror lock-up to minimize motion at every possible point.

The use of electronic flash with its inherent high speed flash duration is most helpful. This is especially true as at great bellows extension, a lot of light loss is encountered. Flash provides these high light levels required for appropriate exposures. As a side benefit, the use of high shutter speed synchronization will also help reduce image deterioration due to internal camera vibrations. As a rule, I generally use 1/250 to 1/500 second shutter speeds at ISO 100 with flash. With these settings I can use the “sweet spot” aperture of F8.0 for highest resolution.

Extreme Depth of Field techniques are exceptionally useful in macro, but the technique is not limited to macro images alone. Remember, DoF is affected
by aperture, lens-to-subject distance, and lens focal length. So you are able to use EDoF whenever given aperture and selected focal length precludes deep DoF.

Copyright © 2012 Brian Loflin. All rights reserved.