Scabious Close Up

Digital cameras are getting more and more feature rich with each new version.  The problem is it is very difficult to keep up with all of the functions they offer, like the Nikon D850's new focus shift shooting.  

Not that it is that intuitive to use; you would hope it would allow you to set the near and far point of your focus range, allowing you to choose the number of shots to take based on the aperture you set.  Unfortunately, and this is the same case with the Olympus focus bracketing function, it only allows you to set the near point and then choose an arbitrary number from 1-10 to reflect the spacing between each new focus point, along with the number of shots.

It was worth some experimentation today, though I'm not sure I'm any the wiser after trying various settings.  I like to work with a wide aperture to soften the background of these images, so started with a 'narrow' setting of 3.  I needed 60 shots to capture sharp detail from front to back of the flower.  That appeared like overkill for this subject so I tried again with a setting of 7.  Still 20 shots for this image, though it does appear to have captured detail throughout the bracketed shots.  

I was using Helicon Focus to stack the images so I tried again, using every other image from the series I'd taken.  Comparison of the two stacked images at 100% left me thinking they were indistinguishable and only at 200% could I discern a slight banded softening in the second shot.  I'm now confused as I was shooting at about minimum focus, at wide aperture of f5.6, using a 105mm lens.  I would have expected to need to use a setting to keep the focus shift to a minimum.  I'm going to need to be a bit more scientific and use a ruler, or similar to see what is going on next time.  

Helicon remote works the way I would intuitively expect, setting the near and far point and it then calculates the number of images needed based on the focal length - it will be interesting to do a side by side comparison of the two techniques.