Finding the proper camera settings and accessories for macro videography is much more a process of trial and error, but there are some factors to consider. Macro lenses and microscope optics will have very shallow depth of field and possibly required powerful illumination for ultra-high speed events such as shockwaves, crack propagation, cavitation in bubbles, and explosions.
Subject matter and size, working distance (WD), and field of view (FOV) are some essential when selecting the proper optics. Macro lenses typically offer a magnification ratio of 1:1 or greater, meaning that the size of the subject in the image is equal to or larger than its actual size. This capability is essential for achieving detailed and high-quality close-up images. Microscopes can provide much higher magnification levels than macro lenses.
Macro and Microscope Lens Options with Image Examples
One of our popular macro lenses is the ZEISS Milvus 2/100M which featuring a high1:2 maximum magnification for close-up shooting. Capturing the tiniest details with 1:1 magnification is the Zhong Yi Optics Mitakon 200mm F/4 Macro lens. Adding a Kenko TELEPLUS HD 2x DGX teleconverter, installing it between the lens and the camera body, will increase the effective focal length of your lens by 2x.
The Model K1 CentriMax is Infinity's Optics premier all-inclusive CentriTel® system long-distance microscope. The Model K1 CentriMax can first be brought to a selected working distance and field of view. Then, by using its internal focus adjustment, the focal depth can be ranged without essential magnification change--from a fixed position. This allows both precise "montaging" and precise dimensional measurements to be made—even at significant distances from objects.
Here are some examples of microscopic optic options with ultra-high speed Pharsighted E9-100s camera. The E9-100s can reaches 326,923 frames per second (full frame: 640 × 480 pixels) and up to 2,720,000 frames per second at a lower frame size (640 × 32 pixels).
Visual examples of microscopic optic options with the Pharsighted E9 100s ultra high speed camera
Handy tools we use to help with focusing and frame with macro and microscope lenses:
Pocket USAF Optical Test Pattern from Edmund Optics is a pocket size test pattern on a durable vinyl laminate card.
Digikey PCB ruler to show pitch examples and the trace width examples, on this side, were positioned on the edge so they could be placed over a PCB trace to estimate what width was used.
Lighting Options for Microscopic High Speed Imaging
There are many types if lighting options to accompany high speed cameras. To properly visually demonstrate these lighting senecios, we need to film a extremely fast event. A great testing subject that is considered a safe firework for all ages is a pop it or bang snap. These can display explosions in a small form factor that are visually pleasing in high speed imaging.
Our test subject: TNT Pop it
For these visual examples, we will be using a bang snap. A TNT Pop Its belong to a class of novelty fireworks collectively called bang snaps. Similar products are called snap-its, poppers, and party snaps. The "rock' is gravel or sand that has been soaked in silver fulminate. The coated grains are twisted into a piece of cigarette paper or tissue paper. When the bang snap is thrown or stepped on, the friction or pressure detonates the silver fulminate. (article ref.1).
Continuous High Output LED Illumination
GS Vitec MultiLED lamps cover all applications of high speed cameras and many applications in the machine vision market. Some fixtures cover sub microsecond exposure time, monochromatic light or give you enough light to fully close aperture at some microseconds exposure time. With digital controls to achieve high luminous outputs in both continuous and pulsed operation, there are multiple operation setups for users.
Example of the Pop it and GV Vitec continuous high powered LED system with GX8 controller
Pulse Diode Laser Illumination
CAVILUX Smart UHS is a powerful pulsed diode laser light source with very short pulses and very high repetition rates. It is an ideal light source for ultra high-speed cameras up to 10 MHz. CAVILUX Smart UHS can generate pulsed light power of hundreds of watts at as short as 10 ns pulses. The light output is essentially monochromatic with low degree of coherence, which is ideal for illumination purposes as there are no chromatic aberrations or speckle.
For this demonstration, we used a TTL pulse to trigger the event from the bang snap cutting a laser beam signal. The trigger information signal would output from the E9-100s to the UHS controller with a BNC connection. Lining up the impact of the bang snap with the metal surface and the pulse of the Cavitar Smart Laser, we can use the sign delay of the IO channel in the camera to offset.
Real time video:
Real time video of bang snap cutting the capture laser beam triggering the camera and pulsing the Cavitar Smart UHS system
Example of the bang snaps and offset difference of the trigger signal to the Cavitar UHS
LED Strobe Illumination
The GS Vitec GS-8 LED system is specifically designed for macro- and microscopy with pulsed light illumination down to 50 ns (color LED) and 100 ns (white LED). White LED or color LED up to 8 separate LED heads synchronized in one unit. This is a great substitute for laser based illumination.
Example of the bang snaps and offset difference of the trigger signal to the GS Vitec GS-8 along with front and back lighting techniques
For any follow up questions, please fell free to contacts us.