The following software is available for the automated stacking a series of photographs to create a greater depth of field image than there is in a single shot. All are either free or offer a free trial, so I suggest doing so before deciding on one. I find that some are better in certain situations than other ones.
This is FREE software written by Alan Hadley that is capable of great results. The files are downloadable from his website and offer a variety of options on aligning and stacking images. A support group on yahoo is where you can get help on the software.
This is a commercial software stacker with licenses currently ranging from $39 to $289 excluding taxes. The price varies according to whether you are a student or not and if you want to sell the resulting images.
Helicon Focus is another commercial stacking solution. It comes in 3 versions – each with one year or unlimited licenses. This sees the price ranging from $30 to $240. Included in the two more advanced versions is Helicon Remote for PC desktop – this can automatically stack images using a lens that can alter it’s focus Eg Canon 100mm Macro Lens. A new Android app is available FREE on google play – See my article & tutorial on using these: – Using Helicon Remote & Tutorial on Helicon Focus
Photoshop from CS4 includes the ability to align and stack macro images. This works well with a smaller number of images I find. But if you have it already the it is well worth looking into before buying something else. I have a tutorial on using photoshop for stacking : – Tutorial on Photoshop Stacking