Take your photography to the next level and beyond...

  • NEWS
  • REVIEWS
  • INSPIRATION
  • COMMUNITY
  • COMPETITIONS

Why not join for free today?

Join for Free

Your total photography experience starts here


Christmas Prize Draw 2017

Practical Microphotography Tips With Huub De Waard

Practical Microphotography Tips With Huub De Waard - Insect macro photographer extraordinaire Huub de Waard is back with some practical tips for microphotography.

 Add Comment

Close-Up


Dutch photographer Huub de Waard is no stranger to Microphotography and he has already written two previous articles for ePHOTOzine - Microphotography tips and information and Microphotography tips for insect photography

Here, Huub looks at the practical side of Microphotography and includes handy information for camera settings:

Ant

Black Garden Ant: Magnification 8, f/6.4, ISO 100 and 1/250 sec

The world of insects, spiders and other small forms can be enjoyed on any beautiful day from early spring until late autumn. I can step out of my house on any sunny morning with a cup of coffee and leisurely browse the garden to see where the action is. Or I can choose my spot and watch and wait. And with a little patience, insects and spiders will show themselves and sometimes seem to pose for the camera. Watching the world of gardens in this way quickly reveals that it is truly “a jungle out there” – a jungle of small predators and prey striving for survival. Walking through any flower garden, you’re likely to see bees, hoverflies, and any number of unrecognised insects flying around or walking upon the petals and blossoms of the beautiful flowers. Microphotography can uncover amazing details of the mysterious world of insects. This amazing world of insects is right outside the door of virtually every home.

Introduction to Microphotography describes microphotography as the extreme form of macro photography, dedicated to the photography of very small objects from life-size to modest enlargements of up to about 20. Working with these large magnifications means that the subject is only a few centimetres in front of the lens.

hoverfly 3

Small Cheilosia Male Hoverfly:  Magnification 10, f/6.4, ISO 100 and 1/250 sec.

Effective f-stop

A camera's aperture setting controls the area over which light can pass through the camera lens. It is specified in terms of an f-stop or f-number value. An f-stop is defined as the ratio of the focal length F to aperture diameter D. For example, if the focal length is 32 mm and the aperture diameter is 2 mm, the f-stop is 16 and the aperture would be expressed as f/16. The area of the opening increases as the f-stop decreases. In photographer slang, when someone says they are "stopping down" or "opening up" their lens, they are referring to increasing and decreasing the f-stop value, respectively.

In order for a camera lens to focus progressively closer, the lens apparatus has to move further from the camera's sensor by using modestly priced equipment like extension tubes, continuously adjustable bellows or in my case the more expensive extreme macro lens Canon MP-E 65 mm f/2.8. However, once one approaches greater magnifications, the lens becomes so far from the sensor that it actually behaves as if it had a longer focal length. At 1:1 magnification, the lens moves all the way out to twice the focal length from the camera's sensor. The most important consequence is that the lens's effective f-stop increases because the effective focal length increases. This has all the usual characteristics, including an increase in the depth of field, a longer exposure time and a greater susceptibility to diffraction. The effective f-stop is approximated by the equation effective f-stop = f-stop*(M+1) where M is the magnification.

A teleconverter is a secondary lens that you position between your lens and the camera body. It will increase the maximum magnification ratio and the effective focal length according to its multiplier M without affecting the working distance. The resulting effective f-stop is given by f-stop*M and the effective focal length by F*M.

huntingbug

Common Damsel Bug: Magnification 9, f/9, ISO 100 and 1/250 sec.

Diffraction

Diffraction is an optical effect which limits the total resolution of your photography - no matter how many megapixels your camera may have. It happens because light begins to disperse or "diffract" when passing through a small opening (such as your camera's aperture). For an ideal circular aperture, the diffraction pattern is called an Airy disk, after its discoverer George Airy. When the diameter of the Airy disk's central peak becomes large relative to the pixel size in the camera, it begins to have a visual impact on the image. The effect of diffraction is normally negligible since smaller apertures often improve sharpness by minimising lens aberrations. With greater magnification, you increase the effective focal length, so you also increase the effective f-stop. The aperture remains at the same diameter regardless of magnification. Longer focal lengths cause light to travel further before hitting the camera sensor - thus increasing the distance over which the Airy disk can continue to diverge. The effective f-stop is the most important determinant of diffraction and thus the resolution that the lens is producing at the detector. Here resolution is defined as the ability to distinguish two very small and closely-spaced objects as separate entities.

You are most likely to encounter diffraction when at high magnification in microphotography.

For example, the Canon extreme macro lens MP-E 65 mm f/2.8 has combined with a 2x teleconverter a maximum magnification of 10:1. Selecting f/6.4 at magnification 10 will result in an effective f-stop of 76.8.

You might be inclined to think that the effects of diffraction are now obliterating all the detail you worked so hard to get. In normal photography, the more you decrease the aperture, the more the effects of diffraction affect the image. Since the detail in the image is not getting larger, the more detail you lose as the Airy discs grow. When it comes to microphotography, you’re magnifying the detail as you increase magnification. The facets of an insect’s eye become gigantic, and the fine details of the facets are visible with enough magnification, to the point where they span large clusters of pixels ... where the Airy disc of diffraction may only span a few pixels. Eventually, the effects of diffraction will prevent you from continuing to make useful gains with additional magnification. But you can push magnification very far as I have shown with my photography.

shieldbug

Green Shield Bug: Magnification 6, f/14, ISO 100 and 1/250 sec.

Sensor Dust

When the size of the aperture is large and the effective f-stop is small (e.g. effective f-stop 5.6), light rays reach dust particles that are sitting on the sensor filter from different angles. Remember, although I refer to this as “sensor dust”, dust actually never touches the sensor, because there is a thick filter that sits in front of the camera sensor. Therefore, by the time light reaches the physical sensor, it is spread out on a very large area, making dust appear as a large, light blob with a soft ring. When using very large apertures like f/1.4 on fast prime lenses, these blobs might be so washed out that they might be practically invisible to your eye. That’s why portrait photographers notice dust less often than landscape photographers!

When the effective f-stop value is significantly larger, say 76.8, light rays coming from the lens diaphragm are perpendicular to the sensor filter. Because the angle is more or less 90 degrees, dust specks also cast direct and defined shadows on the sensor. That’s why dust shows up in images much smaller, darker and with more defined edges at large effective f-stop values.

The clone and spot healing brush tools can be very effective ways of removing dust spots. However, this only works if the spots appear in easy to remove regions of your photo, and if the dust problem remains minor; eventually you'll still have to get the sensor cleaned. Personally, I prefer a sensor brush. A sensor brush works by electrostatically attracting dust particles to its fibres, and not by actually scrubbing these off the sensor physically. It will likely remove all but the most stubborn dust, and generally has little risk of scratching if it only makes light contact. There are even types which are designed to surgically remove individual particles without having to sweep over the whole sensor.

small wasp

Small Ichneumon Wasp standing on dandelion, size around 1.5 mm: Magnification 8, f/8, ISO 100 and 1/250 sec.

Micro lighting

By far the biggest challenge to microphotography in the field is getting enough light on the subject. Light is lost when using macro lenses, extension tubes and teleconverters. As magnification increases, depth of field decreases rapidly. Due to loss of light and depth of field considerations, it is advisable to use a ring flash or twin flash when shooting micros. It will allow you to shoot at a reasonable speed, yet enable you to use a small aperture for sufficient depth of field and a fast shutter speed (e.g. 1/200 sec) to capture moving insects. It becomes a necessity for most shooting above magnification 1:1 simply because there is normally not enough light.

Front lighting will provide better colour saturation, while side lighting gives your subject more light on one side than the other. This gives the picture a greater sense of depth and dimension even though it’s a two-dimensional image. A ring flash will provide an even level of lighting so that your image won’t have strong highlights and shadows, but the downside is that this often looks unrealistic because the flat front lighting produces a flat appearance.

A twin-flash system will produce a more natural lighting situation and the results are often more appealing because there is more dimensionality to the image. Being able to choose the position of twin flash units allows you to mix front lighting with side lighting. Twin-flash units also allow you to change the output levels of light. One flash may be brighter than the other, giving you much wider latitude for creating more natural shading and a greater sense of depth. The two flash tubes/heads can also be independently rotated around the lens rim to adjust the location of highlights and shadows, thus better matching the shooting situation and creative intentions of the photographer.

Getting the light just right is never simple. While single or twin flash units give us the opportunity to add light, sometimes, even with controls that allow us to vary the light output, the added light is still too harsh. To soften the light, you can choose to use flash diffusers. Diffusers are translucent plastic covers placed over the flash head so the light passes through them, softening the light.

 

About the author

Huub de Waard is a Dutch wildlife photographer who specialises in insect macro photography. He photographs very small invertebrates so close-up that they are transformed into large subjects.

Through his images, he aims to highlight the different characteristics of a variety of species - and their individual charm.

He does not apply focus stacking and all of his pictures are single images. His work can be found at http://www.huubdewaardmacros.com

Join ePHOTOzine and remove these ads.

Explore More

There are no comments here! Be the first!


Sign In

You must be a member to leave a comment.

ePHOTOzine, the web's friendliest photography community.

Join For Free

Upload photos, chat with photographers, win prizes and much more.