Focus Stacking

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Focus stacked image in Helicon Focus. Two Images combined. Both shot at F/8.0 on an Olympus EM5. One image was focussed on infinity whilst the other was focussed on the foreground.
Focus stacked image in Helicon Focus. Two Images combined. Both shot at F/8.0 on an Olympus EM5. One image was focussed on infinity whilst the other was focussed on the foreground.

 

One of the great advantages of small sensor cameras for the Landscape photographer is the increased depth of field that can be achieved, even at relatively wide apertures. For example, I shoot most of my landscapes with the Olympus EM5 set to f/8.0 where the image quality is still excellent and depth of field is front to back. Or is it?

Take a look at this example (all images are at 100% magnification and haven’t been sharpened).

This first example is the very bottom left of the image on this page which was shot at f/8.0. The point of focus is on the near foreground.

Bottom left corner with focus in the foreground.
Bottom left corner with focus in the foreground.

The heather in the image is blowing in the wind but you can see the grass is very sharp.

In this next image you can see the distant horizon for the same image.

Distant hills with point of focus on the foreground
Distant hills with point of focus on the foreground

This is actually quite soft and not as sharp as if we had focussed at infinity. In this next shot you can see what happens when we do focus on infinity.

Distant hills with focus on infinity
Distant hills with focus on infinity

This second version of the distance is substantially sharper but look what’s happened to the foreground in the bottom left corner.

Bottom left corner when the focus is on infinity
Bottom left corner when the focus is on infinity

It is possible to be a little more careful with the point of focus selection and achieve a better balance but this doesn’t give us the ultimate sharpness and depth of field. What we really need to do is combine the two images into a single image which gives a full depth of field. That’s where focus stacking software can help.

I have been a long time user of Helicon Focus for focus stacking but I have to admit that I stopped using it for a while when I switched over to Micro 43. That’s because I thought I could achieve the depth of field I wanted and also the interface was a little clunky. Recently though I decided to update my version of the software (I have a lifetime license) to version 6. What a pleasant surprise. The interface is a joy to use and the software is very fast.

The software offers three methods of blending and all do a good job. My preferred option is B (something called a depth map) where I can set the Radius and Smoothing. I have found that sometimes the default settings leave small areas which don’t blend perfectly. But by adjusting these options a little it’s usually possible to achieve a perfect blend. Another nice feature of the software is that it has retouching brushes. Just pick the source image and paint an area onto the finished image, it’s that simple.

If you haven’t tried Helicon Focus before and you want to achieve the ultimate depth of field, you will find it quite a remarkable tool.

That’s probably it for this year. Have a great Christmas and New Year everyone.

4 thoughts on “Focus Stacking

    Greg Butler said:
    December 24, 2015 at 7:41 pm

    Beautiful image. This scene would lend itself to even more shots. I find the FocusStacker app invaluable for telling me all the focal distances I need, how many, what f/stop, and how sharp of an image I can expect.

    You image would probably take nine shots for the optimum results.

      thelightweightphotographer said:
      December 26, 2015 at 12:00 pm

      Hi Greg. Pleased you like the image. I did do some with 4 images and to be honest, you can’t see the difference. Even looking at the depth map, the software was taking very little information from one of the images. But I do get your point, and with a full frame camera I would agree that you need to take a few more than just 2 shots.

    David said:
    December 25, 2015 at 4:52 pm

    Merry Christmas, Robin. Thanks for all your interesting and educating posts this year.
    Best wishes for 2016

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