John this technique is about 10 years old. Google focus bracketing
Overcoming the Challenge of Depth of Field in Macro Photography
Posted on Sunday, 16 February, 2014 by Xenedis
As anyone who has experimented with macro photography will know, this style of photography, and more specifically the nature of the subjects and lenses used, makes achieving a suitable depth of field very challenging.
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To produce a focus-stacked composite image in Photoshop, the technique is as follows:
1.After raw conversion, load all of the raw files into Photoshop.
2.One at a time, and in sequential order (this is important), copy each image to the clipboard, and then paste it as a new layer into the first image.
3.Rename the layers using a logical naming scheme (eg, IMG_0001, IMG_0002, etc.).
4.In the layers pallette, select all of the layers.
5.Click the Edit menu, and select ‘Auto-Align Layers…’.
6.Set the Projection set to ‘Auto’ and click OK. Photoshop will align the layers.
7.Click the Edit menu and select ‘Auto-Blend Layers…’.
8.Make sure that ‘Stack Images’ is selected, and click OK.
Whole article here:
