Monday, June 25, 2012

Focus Stack of a Salvia


I saw this flower last spring and have tried to get acceptable photographs with a single shot.  I do not want to shoot it directly on but still wish to see the full depth of all of the spikes and I want the background to be highly blurred.  The weed is generally mixed in with other grass so the background tends to be busy and distracting, so focus stacking was an ideal alternative.  Neighboring blossoms are seen nicely out of focus.  I utilized Zerene stacker to generate the composite.  This program has a helpful editing capability which came in handy to pick a single image with the best shot of the fly and make sure that it is used in the composite.  Nice feature.


Tuesday, June 19, 2012

Focus Stacking for Macro and Close-up Photography

Focus stacking is a relatively new digital photography technique which can, to me, produce startling results.  To generate the images shown here, I utilized a focusing rail (Novoflex - Castel-L), my D700 camera and Nikon 105mm VR II lens combination, a steady tripod and Zerene Stacker software.  Since, I am interested primarily in outdoor photography, I also now use some sort of mechanism to steady the target.  A breeze is always blowing. 

I always operate in the Manual exposure and focusing mode.  The camera is arranged the appropriately aimed at the target and manually focused in LiveView mode to where the focus plane is just before the target and the first image is collected and then advanced in steps moving the focusing plane through the object collecting multiple images.  The step increment is selected depending on the depth of field.  Once collected all images are then processed identically.  I generate Jpegs and the resulting stack is input into the software which creates an image made up of "in-focus" portions of each image.  In this way, one still has the advantages of a sharp DOF fall-off in front of and behind the first and last image combined with a large DOF. 

The first image is a stack of 30 images of a Poppy which is just blooming.  The resulting images are still startling to me.  One sees how each image plane is in focus as the rail is used to step through the scene, but the entire scene only becomes "in-focus" as it is processed.



To me the detail is just stunning.

The next three images are stacks of Thistle blooms.  I searched for plants which had bright Magenta coloring.  The first image is a close-up of the blossom which is just about to emerge.  The focus distance was relatively close, so the DOF is narrow and about 50 slices were collected.

The second and third images were of a wider view and fewer images were needed. 




As with both Macro and Telephoto photography, what one sees with the naked eye and through the lens, is strikingly different but with stacking the difference is even greater.  Through the macro lens, one sees the magnified scene but only a narrow region is in focus.  When all put together by the software, the results show all the detail in each image.  It really is amazing!