An Alternative to Focus Stacking

[Michael Erlewine]

I am not saying this is a great solution, just that it is one solution. And that is to use Chroma Key instead of stacking focus (with resulting artifacts) or using a one-shot photo at a narrow aperture, which means little to no bokeh.

I am looking for a sharp foreground image against a soft bokeh background… usually.

Chroma key requires two layers of image, a background layer that can be as bokeh as all get out, and a foreground layer than can be a sharp close-up at higher aperture or even a carefully-stacked shot. The two are merged together in Photoshop and become one.

For this to work, the foreground shot (in this case the flower) has to be shot against a solid background, using a green or a blue background. For nature, the choice would be “blue” because green occurs more frequently in nature than does blue. We want a color that is not in the foreground image. In this case, I used a black background, just a piece of black velvet. My thanks to an anonymous Nikon-Gear member for his suggestions.

An important point is that it is best to shoot the foreground image on the same background it naturally is, but just to make the foreground image very much in focus and the background image blurred out to bokeh. That way they complement one another. That is what I have done here. Actually I took a background shot and blurred it in Photoshop to accent the effect.

Next, in Photoshop, place the background image on a layer below the foreground image. Then using the Magic Wand, select the background color we want to remove (blue, green, black, etc.) and select that color and delete it. The result is that the background image shows through in a nice bokeh. You may have to remove the background color in several steps looking carefully in the foreground image for places where it occurs.

I am not saying this is a great alternative or whether I will use it for my work, but it is a fair way to avoid the retouching artifacts that a normal focus-stack is heir to. Here is my first attempt, which looks sort-of OK. I would have to work on the upper stem and leaves of the flower more to make it really blend in, but here it is for a quick look, a proof of concept.  I imagine, like anything else, I could get good at it over time.

I just put this out there as another alternative to the eternal problem of foreground and background struggles.

Nikon D810, El Nikkor 105 APO

[Grahame Hamblin]

Thanks Michael will give it a go.
Grahame

[Frank Fremerey]

Seeing the image I would never have been able to guess how you did it. Thank you for sharing your insights

....what a pop out & how nicely retouched the borders are.

[pluton]

It works.  It will be a trick to make it look as realistic as your "straight" shots or the very finely-honed focus stacks. By the way, when you key using black or white,  a "chroma-key" composite becomes a "luma-key".

[Airy]

The result is pleasant, although the subject is not forgiving : the hairy stems... I guess focus stacking would provide a slightly better result on that particular detail. But to me at least Chroma Key is the only feasible alternative.

[Michael Erlewine]

The result is pleasant, although the subject is not forgiving : the hairy stems... I guess focus stacking would provide a slightly better result on that particular detail. But to me at least Chroma Key is the only feasible alternative.

Actually, in this case, the main flower is focus stacked, FYI.

[Dr Klaus Schmitt]

It still looks "staged", but for a first try it is very good IMHO