6. Increase Depth of Field.

The Depth of Field (DOF) is the portion of a scene that appears acceptably sharp in the resulting image. The DOF is determined by the subject distance (that is, the distance to the plane that is perfectly in focus), the lens focal length, the lens f-number, and the format size. See the Depth of field article on wikipedia.org for a detailed explanation. The small depth of field is often a problem in macro photography. Also in "landscape" photography this can be a problem. Lots of photographers strugle with the fact that it is extremely difficult to have complete sharpess (focus) from foreground to background.
This is where techniques like focus-stacking are trying to achieve an increased depth of field. Focus stacks are actually multiple images of the same scene with the focus set at different distances. Enfuse and Align_Image_stack can be used to increase the Depth of Field for such image sets with limited DOF. ImageFuser is your friend when it comes to a user-friendly Gui to both programs.

This chapter is not to give you a theoretical background, but just to get you going.

Note: These images are not mine as I have a "cheap" consumer camera that doesn't allow me to vary focusing distances. The images used in this chapter are copyrighted by Höss Lajos. He has generously made them available for use in this chapter.

Used images

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The images have their focus at different distances ranging, from the foreground to the background.
Note: It is very important that your images are correctly aligned.

Workflow

On the "Align_Image_Stack" tab check the "optimize all except first" checkbox.
On the "Enfuse" tab check the "Hard Mask" checkbox. Also set wExposure and wSaturation to 0, set wContrast to 1.

The settings described here are the most important settings. All the other settings are left at their default values. It sometimes helps to play a little with them as well, especially with the settings on the "Enfuse Expert" tab like the "Contrast Window Size" and contrast enhancement in the "Edge Scale" settings. All of this is explained in detail in Christopher Spiel's enfuse manual (1.).

Further sources for reading and examples

(1.)Focus Stacks - Depth-of-Field Increase (enfuse extend manual) by Christopher Spiel.
Extended Depth-Of-Field Using Panorama Tools by Rick LittleField.
How to obtain a greater depth of field in macro photography by Eduardo Perez