Not everything on this site is deep-sky stuff, occasionally I publish something interesting that’s associated with the photographic process. This one has recently kept me occupied. With deep-sky images we stack lots of sub-exposures to push up the signal to noise ratio in the final image. But there’s other types of stacking we can do as well. We can stack images of wildly different exposure (HDR) to get an image with a big dynamic range (this is also a technique used in deep-sky imaging) – and we can also take a set of images of the same scene with different set foci to get an image where all objects in the scene appear to be in focus. This macrophotograph of the central region of an Orchid was taken in this way. If you consider that the distance between the part of the flower nearest the camera, to the furthest part was in excess of 2 cm, you can see the amazing effect that focus stacking can have!
