![]() In the example used for this tutorial we will use a set of two image one where the focus is on the foreground and in the other the point of focus is in the distance. In order to create an image using focus stacking you are going to need to shoot at least two identical images where only the point of focus changes. These images are then combined into a single image by taking the in focus area from each image and merging these together to give a much greater depth of field. The change in focus point is used to move the depth of field over the entire distance that needs to be in focus. This involves taking multiple identical images where only the point of focus changes. The solution to the depth of field problem is the technique of focus stacking. It can be very difficult to render objects sharp in their entirety. ![]() Here you can find that even using a very small aperture only gives a few millimetres of depth of field or even less. If you are interested in macro photography, the problem is even more acute as the subject is often so close to the camera. It then becomes necessary to use a much smaller aperture which is probably outside the optimal working range of the lens. ![]() Unfortunately, this may limit your depth of field and mean that more distant objects are out of focus. So if you are shooting a landscape with an object looming large in the foreground, it’s likely that you will focus on the object to ensure it is sharp. One of the problems we face with these types of photography is that as the point of focus gets nearer to the camera, the depth of field lessens. But in other forms of photography such as Landscapes and Macro you might want to maximise the depth of field. For some images you might need very little, for example in portrait photography where you throw the background to the subject out of focus. How much depth of field you need for an image is a bit of a moving target. Unfortunately, most people don’t have one of these cameras, or the patience to use one. This can be used to increase depth of field beyond what could be achieved with the aperture alone, allowing the aperture to remain within the optimal working range. This is one of the reasons many Landscape Photographers favour large format technical cameras which allow special movements such as tilt. Ideally you want to keep your aperture in the range where the lens performs at its best. The drawback with this approach is that as the aperture becomes smaller, something called diffraction sets in and the image sharpness suffers. You then carefully select the point of focus for maximum depth of field. The traditional approach (adopted by most) is to use a very small aperture. Trying to achieve a significant depth of field in your images can be quite frustrating. There are times when the depth of field you can achieve in a single shot just isn’t enough. Zerene gives the best final image by a large margin and the in camera stacking is noticeably better than Olympus Workspace.A focus stacking video to accompany this tutorial is also available. I have compared Zerene with Olympus Workspace and Olympus in camera stacking, by stacking the same bracketed images with all 3. Try them both to find out which interface you like the best and to decide if their output is worth the purchase price. You can try both programmes for free, as each offer a free 30 day trial. The personal edition of Zerene is currently $89USD for a lifetime licence and the lite version of Helicon is $115USD. ![]() The advantage of the Helicon approach is a simpler workflow.īoth programmes come in personal, enthusiast, and commercial variants with Zerene currently slightly cheaper in each version. The advantage of the Zerene approach is that it leaves raw conversion algorithms (and their updating) to the specialists. Zerene's philosophy is to let the user use an external raw editor (Lightroom, Capture One, etc.) to convert raw files to 16bit TIFF files which are then imported into Zerene to be stacked. One of the major differences in workflows is the way they handle raw files. Helicon has a more user friendly interface. The end results from either programme will be indistinguishable but their interfaces and workflow are different. Both do a very good job of stacking and offer the ability to edit the stacked images to correct any small stacking errors. There are two major specialist stacking programs, Zerene Stacker and Helicon Focus.
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