Originally Posted by
DanK
I don't have a link to one that is written without regard for the specific software, but there are good tutorials on the zerene.com site for stacking with their software, which is what I use.
For taking the photos, the key is to start with the closest point you want in focus, rather than starting at the back, because the framing of the photo will change as you refocus, and starting at the front end insures that you aren't framing too closely. Then just take a series of photos, focusing slightly farther back each time, until you have one that is sharp at the rear-most point you want in focus. I generally overshoot the mark just to play it safe.
The only hard part of this is learning how much to change the focus each time. This is trial and error at first, but the principle is that it is better to err on the side of too many shots close together. Even using software to control the focus doesn't necessarily solve this problem. When I bought Helicon remote, I found that the intervals were too large for my lens and camera, and I had to try several different adjustments before it worked correctly. However, once you have done this by hand a number of times, it becomes second nature.