Re: A Challenge to Focus Stacking
3
AeroPhotographer wrote:
My goal was to show that surprisingly deep depth of field is achievable without stacking, if you shoot from a greater distance. That's because depth of field is proportional to distance squared. So double your distance and you quadruple your depth of field.
But you lose detail from the cropping. Here are some comparisons between a focus stack at f/3.5 versus cropped single images at f/11, f/16 and f/22.
Here is a comparison of the field of view for the stack, on the left, and one of the single images, on the right.

Here is a comparison to show the depth of field as between the uncropped focus stack at the top left and the three single images cropped to match the field of view of the stack. (f/22 top right, f/16 bottom left, f/11 bottom right.)

Here is the same comparison, but at 50% for the cropped single images and at 27% for the focus stack to match the fields of view.

Here is the comparison at 100% for the cropped single images and at 53% for the focus stack.

In this case the focus stack has greater depth of field than the f/22 single capture and better detail across the whole in-focus range than the f/11 single capture has in its best in focus range.
You can use post processing to get as much as you can out of single images, but there are limits to how far you can get with that and how large an image you can produce with image quality that is sufficient for your needs.
However, with stacking there are practicalities to consider, especially with live subjects in their natural environment, which may present difficulties for stacking such as moving around, parts of them moving and/or being on something that is moving around in the breeze. They may also be located in an awkward to get at position for which single shots are practical but multiple shots suitable for focus stacking are not.
There are therefore trade-offs to explore to find what combination of magnification, aperture, cropping, stacking and processing best fit your preferences for the look of your images and the nature of your subject matter.
There are people who use stacking successfully for live subjects in the field. Using huge numbers of captures for a stack is obviously not being to be practical much of the time for live subjects in the field, but good results can be obtained with just a few images for a stack, as few as two sometimes, including hand-held.
My own preference has been to stick with single captures, use small apertures and use strong post processing, with varying amounts of cropping depending on composition, to produce images that are relatively small at 1300 pixels high.
I typically shoot at f/45 on full frame, which produces effective f-numbers of around f/56 to f/135 for the magnifications I use, and equivalent f-numbers on other formats. This is the sort of images I end up with.










However my image is only 945 pixels wide, which is 30% of yours. But 945 pixels does quite well in many places.
Alan