Scientific Macrophotography - Methods & Gallery

All photos are my own, created entirely by me. Use the menu at the top of the page to view the gallery

I use a software called zereneStacker for focus-stacking and Photoshop/Lightroom for edits and cleanup

Scientific Macrophotography: Technical Methodology & Application

Scientific macrophotography in biological research utilizes specialized optical systems to image microscopic plant structures at relatively high magnifications. The fundamental distinction between scientific macrophotography and traditional microscopy lies in the structural preservation of the specimen. Macrophotography maintains the complete three-dimensional shape and structure of botanical subjects throughout the imaging process, while conventional microscopy usually requires destructive sampling techniques that often compromises or completely eliminates the original 3D architecture of the sample.

Challenges at High Magnification

At relatively high magnifications, the insurmountable constraint governing image quality becomes the extremely limited depth of field. Magnification and depth of field have an inverse relationship to one another, where increased magnification results in proportionally decreased focal depth.

This means that the "band" of the image which is in focus at one point:

• At 5× magnification: is approximately 10 - 20 microns 'deep'

• At 10× magnification: is approximately 5 - 10 microns 'deep'

These optical limitations ensure that conventional photography techniques are entirely inadequate for full and accurate documentation of three-dimensional botanical structures.

Focus Stacking

Focus stacking has become the standard solution for overcoming depth of field challenges in high-magnification photography. This specialized photography technique involves photographing sequential images across the focal range of the specimen, from 'front' to 'back', followed by digital processing to merge in-focus regions from each frame into a composite image with extended depth of field.

Automated Positioning System (Rail)

Implementation of focus stacking protocols necessitates automated macro rail systems capable of micron-level positioning accuracy. Using this the camera is advanced to the position where the point of the subject closest to the camera is clearly in focus, here is the startpoint. The camera is slowly advanced forward using the rail to the position where the point of the subject furthest from the camera is clearly in focus, here is the endpoint.

Doing this, the total 'depth' of the subject which needs to be imaged has been determined.

Capture Parameters and Calculations

The relationship between three parameters (total depth of subject, distance of each step, & number of steps) follows a simple formula, and allows for the determination of the values required for an ideal imaging session.

The total depth refers to the total three-dimensional span of your subject from its nearest point to its farthest point that requires focus; basically measuring how "thick" the specimen is in the direction of the camera's imaging axis. 

The chosen step distance determines how far the automated rail moves the camera between following frames, most often set to ~80% of the lens's actual depth of field to ensure proper overlap between adjacent images (avoids banding). 

The number of steps is then calculated using the simple formula: total depth divided by step distance, plus one additional frame to ensure complete coverage. 

Example

Photographing a moss that measures 2mm from front to back (depth), selecting a 25 micron step distance, yields approximately ~81 images to completely document the specimen without gaps in focus coverage.