I recently read an article about some scientists travelling around the world, taking high-definition pictures of different species of Ants (link). I was intrigued, and wanted to find out how they do what they do. I think I found out, and will explain the technique here now.
Before I talk about how we do this, I will talk about why I think we do this. I talked a bit about depth of field in my post about aperture (here). In photography, depth of field is related to the magnification. Larger the magnification, the shallower the depth of field is. Hence when taking pictures of small objects using magnification, we often get results such as one below:
As you can see, the entire picture is not in focus.
A big problem indeed. 🙂
Luckily, with image stacking (or focus stacking), we can solve this problem. First thing to do is to take series of pictures, manually changing the focus, so that the first image is the image above, and the final image is the image below:
I took 18 pictures in total. Next step is to open them in Photoshop and put all the pictures as layers in one image.
There might be an easier way, but I created layers by pressing “Ctrl+A” and “Ctrl+C” in the original image, and pasting it as a layer in the final image.
Since all my pictures were taken remotely from my camera, they were all aligned, but otherwise, at this point, press the “Edit->Auto-Align Layers…”. The auto align setting should work. Next step is to blend the image using the following settings:
And this is why I called the method image stacking. 🙂
Voila, we are done… 🙂
The final image:
Now you know. 🙂