(Not the most interesting title for a blog post, I'll admit. )
Most of the work I've posted lately has involved focus stacked
shots, using a very shallow depth of field to achieve sharp focus in the
subject while maintaining a soft bokeh in the background. I was asked recently
if the same results could be achieved by shooting with a deeper focus, applying
a blur layer and painting in the areas I wanted in focus. On the surface, it
seems like it would be achievable. Outside of aligning and merging the original
photos, the rest of the process is very similar.
While out on my daily walk, I found a candidate in this
leaf, all alone on a stem and nicely curled, showing both it's front and back
texture. I shot this at ISO1600 f8.0
1/60sec. (It was late afternoon and a cloudy day, hence the high ISO.)
Next I took 5 shots, in aperture priority mode, at f2.8,
with my ISO at 800 this time (the wider aperture allowed a lower ISO) with
exposures ranging from 1/100-1/200sec, each time focusing on different parts of
the leaf,.
The following is the result of aligning and merging the 5
shots in Photoshop, without any other editing.
I opened the first image in Photoshop and applied a high
pass filter at 2.6 pixels, masking the area of the leaf to reduce the already
high noise level in the background. I applied a levels layer to increase the
contrast and deepen the mid tones. Next I copied the background layer and
applying a Gaussian blur at 62.7 pixels to try and replicate the background of
the second image. Using the quick select tool on the background, I selected the
leaf and applied it in an inverted layer mask to the blur layer. I spent
several minutes with a brush tool cleaning up the edges. The following is the
result.
I switched over to my second merged image and did basically
the same process. I applied a high pass filter at 2.6 pixels and applied it to
the leaf to keep the noise to a minimum. I applied a levels layer to add
contrast and deepen mid tones. Here is the result:
After playing with a few different textures, I decided on
one and applied it to both images, switching the blend mode to Soft Light at
100% opacity in both images.
My conclusion? I prefer the focus stacking approach. Once I
have the merged layers, I can much more easily apply sharpening to it than I
can paint in a blurred layer mask. In this particular image I managed
reasonable results, because the leaf was alone, and had clean edges. Even
still, I think there is an unappealing artificial look to the image (which was
reduced when I applied the texture). My recent shot of burst milkweed pods
would have been impossible to do in this way. The variation in focus in the
surrounding areas that don't make it in the focus stacking make for a more
natural looking image, in my opinion. Lastly, I find that naturally occurring
bokeh looks nicer than one I artificially produce in Photoshop. This is just as
likely to be my own inexperience in Photoshop as for any other reason. I tried
using other blur filters and was not able to replicate what I achieved by
shooting with a low aperture.
The beauty of Photoshop is that there are multiple ways to
achieve the same or similar results. Each can be used according to the dictates
of the image being edited, and the comfort level of the person editing the
image. I have developed a work flow that I am comfortable with and get good
results with. That doesn't make it the best way, just the best way for me. My work flow is ever evolving,
as I learn new things about photography and editing, and adapt them into my
creative process.
