Tuesday, October 14, 2014

Macro Focus Stacking


We were recently tasked with shooting a sunflower seed for an ad agency that specializes in agriculture. Their client needed the image for a billboard and print ad campaign. For comparison, sunflower seeds are about 3/8 inches tall by 1/4 inches wide. Billboards, on average, are 14 feet tall by 48 feet wide. So...in order to get images of the teeny, tiny seed as large as possible, we needed specialized equipment. We rented a Canon MP-E 65mm Macro Lens that is capable of 5x magnification and a focusing rail. 

Because of the extreme magnification, we had very little depth of field – say, about the thickness of a sheet of paper. Therefore, we ended up employing a process called "focus stacking." We shot in increments of 1/4 centimeter to capture 15 images of the seed at various focal depths. While none of these 15 images had the seed entirely in focus, collectively, they contained the data needed to generate one focused image of a sunflower seed. 

We used Photoshop to blend the 15 shots together and generate the final seed image. Photoshop masks out the unfocused areas and keeps the areas of the image that are in focus. The end result is a crystal clear image in focus from top to bottom. Stand alone programs such as HeliconSoft and Zerene Stacker also offer this feature. If you plan to do a good deal of macro focus stacking, I'd suggest investing in a stand alone program.

Photography is about problem solving and visually communicating what your client wants to say. This project employed one of the smallest subjects we've ever photographed, and we had a blast figuring out how to show every detail of a sunflower seed!

Wide view of our teeny, tiny set.
Closer view of the set and seed being photographed.

We shot the seed on its side as it was easier to light it horizontally. It was rotated vertically in post-production.


Focusing rail we rented, which allowed us to seamlessly move the camera 1/4 centimeter at a time. 

David concentrating on focusing and shooting every 1/4 centimeter.

The final image with the "stacked" sunflower seed for the billboard campaign.


David's stylized version, with a more dramatic sky.