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Helicon focus rail1/16/2024 ![]() Then the position of the camera is adjusted to the final position of the stack. Pressing the Up/Down button sets the starting point for the stack. StackShot will travel in both directions so it can stack from the foreground to the background or visa versa. Next, using the FWD and BACK buttons the position of the camera is adjusted to the initial starting point for the first picture in the stack. It is desirable to have some overlap of in focus depth between photographs. Since the DOF of our lens at f/5.6 is 0.176 mm, the "Distance per Step" variable in the controller is adjusted to 0.150 mm. In this example we're going to use the "Auto-Distance" mode in StackShot. The auto exposure modes tend to meter the scene a bit inconsistently causing a significant variation in brightness of the photographs over the range of images in the stack. The one difference for focus stacking is that you will want to use full manual mode for both the flash, shutter and aperture. The first step in the stacking process is to adjust your camera and flash settings to get proper exposure. Rik Littlefield of Zerene does an excellent job of explaining how to best determine the step size for focus stacking in an article here. In the ant example below the manual states the depth of field for the Canon MP-E 65mm, at 3x magnification and f/5.6 is 0.176mm or 176um. Consult your lens manual as this information is often published there. Regardless of the setup you choose you will want to have a feel for the depth-of-field (DOF) of your lens and aperture setting. Use whatever lens and camera setup you are comfortable with. There are plenty of options in the photographic world for taking macro photographs macro lenses, microscope objectives, bellows, inverted lenses, extension tubes, etc. Using the Arca Clamps and Plates has the advantage of giving the user the option to quickly add or remove the StackShot from the tripod without any threaded connections. The image below also shows the optional Controller Carrier Kit and Li-Ion Battery for a complete field setup. The Arca Adapter plate drawing can be downloaded here. The Arca Adapter Plate has mounting holes so you can mount the clamp in either orientation. You will need the optional Arca Adapter Plate to firmly secure the clamp to the rail. If you are an Arca Swiss user you would attach StackShot to the tripod as shown below. To mount the camera to the top of the rail, it comes standard with a 1/4-20 stud that will thread into the base of your camera. ![]() In the case you are not an Arca Clamp user you would mount your tripod plate of choice to the base of the rail with one of the threaded holes in the base of the rail and then mount the rail to the tripod. There is a drawing showing the position of the holes here. ![]() StackShot has a dovetail machined into the base as well as both 1/4-20 and 3/8-16 threaded holes. ![]() If you are an Arca Swiss clamp user the image below shows the most flexible setup with all of the extras. The most common of these options is a tripod. There are a lot of options for mounting StackShot, these include a tripod, optical bench, copy stand etc. So how does it work? Let's first start off with mounting options and the electrical connections.įocus Stacked Carpenter Bee courtesy of Alexander Zubrickij This precision controlled rail will take as many pictures you want at whatever step size you'd like (down to 2 um). StackShot automates the movement of the rail and the triggering of the camera's shutter. So what does Cognisys have to offer the world of focus stacking? StackShot. Take picture, move the rail slightly, take a picture (ugh! Did I just bump the camera?), move the rail a little more, it is a fairly tedious process. If you've done this before you know it can be a slow and tedious task. There are more educational links about focus stacking at the bottom of the page. This movement slides the in-focus part of the image through the subject. The macro rail allows finely controlled movement of the camera to change the distance between the camera and the subject. Typically the camera's position is adjusted in relation to the subject of interest by using a macro-rail. You can move the camera, the subject, or change the distance between the lens and the camera. There are several different ways to create a stack of photos. With focus stacking we can create high magnification photos without the limited in focus area (Depth of Field) We do this by collecting several images with whatever depth of field our lenses will provide and digitally combine them to increase the in focus area. Anyone that has taken a close up photo knows that as the magnifcation gets larger the in focus area gets smaller. Wikipedia defines focus stacking as " a digital image processing technique which combines multiple images taken at different focus distances to give a resulting image with a greater depth of field (DOF) than any of the individual source images.
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