Extreme Depth of Field by the use of Helicon Focus

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Entering into the new field of extreme photography, close-up photography, and one can now get a lot more powerful and exciting pictures by simple experiments than ever before. With the advent of latest innovations in field of digital photography one can try out real limits of larger depths of field and keep the resolution to highest. For instance, when photographing a smaller object of the size of a house fly, the required depth of the field is usually 0.1 mm or even less, while the optimum point is generally f/8 or even wider.

The real problem that arises then is of the stopping down of the lens. Of course stopping down offers more depth of field, too much stopping down make the image blurry due to diffraction effect. Thus greater the magnification, greater is the problem encountered. But with the advanced digital photography options, the transactional swapping between the stopping down the lens for larger depth of field and opening up the aperture for good resolution has been relaxed.

The simple techniques, that causes miracles is to shoot a stack of several pictures, instead of one single shot with critical focus plane. Now, while shooting this stack, one has to sweep the focus plane through all the places whose detailing is of critical importance. Later some easy software processes the stack. The actual job of the software is to combine the portions of each photo in perfect focus and create a single photo. Thus, getting your photograph a large depth of field and high resolution at same instance.

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For this kind of photography, all you will need are the following items:

  • A Digital camera with macro-focusing lens or close-up lenses.
  • Ability to focus manually.
  • A PC with Windows installed on it.
  • Helicon Focus.
  • Appropriate subject and sufficient lighting conditions.

This technique is effectual over a wide variety of purposes in field of extreme close up photography. If you are satisfied with the resolution settings of your camera, usually then taking 2-10 frames will be desirable. Getting further into the depth of the technology, one can practically, using current computers and cameras achieve a stack of 100 or even more different foci planes. This enables opening up of the lens to achieve best possible resolution, while still achieving adequate depth of field in order to cover your entire subject.

The result can appear as to be identical to scanning electron micrograph, that too in true color. The major constraint, being that your subject should not move while the photo stack is being shot. 

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Helicon Focus 

Helicon Focus is a software package, which is inexpensive and suitable for this kind of photography. Although it is a commercial product which can be used for free, but under some restrictions. These kinds of packages have complementary capabilities. Generally speaking, Helicon Focus is easier to use. The crux of the matter lies in the processing engine of Helicon Soft's ingenious program, is Helicon Focus, which combines the in-focus areas of multiple exposures of the same subject which are manually focused on different planes throughout the field of view.

This completely focused image which gives virtually unlimited depth of field is a magic played by this software. It further uses the algorithms to create final images. These images are indubitably complex; while the photographers who use Helicon Soft will find its operation quite straight-forward.

The three basic steps needed to use helicon focus 

Initially, one has to find a subject that can be captured using an extensive depth of field. Definitely all that comes to mind are subjects of macro and micro photography. In fact, Helicon Focus enables the photographers to take shots which are otherwise impossible even with huge view cameras. If a scene contains one of the objects occupying a vertical plane just near the camera and other objects in vertical planes enormous distances away, the solution that is most sought is extremely small apertures.

At this case, sharpness is a critical issue to be dealt with sensibly. Always bear in mind sharpness is relative. Thus depth of field may cause the image to be slightly blurred but in fact it may be in focus. With the use of Helicon Focus, everything can be pin-sharp, be it the nearest tree or even the distant hillside. This is possible in helicon focus due to processing of the circles of confusion in the final to reduce to tiny particles. The results are satisfying and in fact natural.

In following step two, one has to mount the camera solidly on a tripod, take several pictures, focusing gradually from far away to close by objects or details. First take one picture; then refocus closer to same object. Follow the same process for the second one and so on. Important to note is that, do not base your refocusing on the distance scale of lens. Instead one has to turn the focus ring in equal degrees or divisions between distant end and the closest point in focus.

Another important fact to be kept constant is the manual exposure for all set of images. And now as you turn the lens gradually back toward the closest point of the subject in question, that you want to appear sharp. Also try to keep your camera and tripod as still as possible. The software will process as many number of shots as you desire.

Lastly, the easiest step of all is to load the images into Helicon Focus and allow it to process the images. Helicon Focus rectifies for the gradual magnification that occurs when you focus from the infinity going back towards the camera. It even modifies and balances for the differences in the exposure conditions.

The real fun is of the process is freedom of zooming in to 100 percent, in order to capture all the details from just by the camera to far away objects, and getting them all in tack sharp focus!