The recording of images of extremely small moving objects or processes requires both ultra-high frame rates and high magnification. Slowmo has a special zoom lens to cover this type of application. When used with the new NOVA S12 high speed camera, extreme close-ups at ultra-high frame rates are possible.


Navitar 12x zoom lens with 2x Nikon mount adapter

A field of view (FOV) of ~1.4mm is attainable with the Navitar lens from a practical working distance of 86mm.

This working distance allows the flexible positioning of external light, focussed past the lens and onto the subject matter. The Nikon mount adapter allows for the full sensor (1024 x 1024 pixels) to be used. If there are space restrictions, the working distance can be extended to 325mm with the use of a 0.25x lens attachment (supplied with the kit).

At the highest magnification, for displacement/resonance calculations, each pixel at 1024 pixel resolution relates to 0.0013mm. With this same setup you can zoom out to a FOV of ~17.5mm.

EFFI-SPOT

Slowmo has recently purchased the new EFFI-SPOT light source from Effi-Lux for sole use with the Navitar zoom lens. The EFFI-Spot is a high-powered extremely bright LED projector with an integrated fan and perfectly suited for close-up scientific and industrial applications. It is also possible to control the light intensity via a dimming control.

The images below demonstrate the amount of magnification possible. All were taken with the Photron SAX2 mono camera with a frame rate of 20,000fps (higher frame rates are possible) at 1024 x 672 pixel resolution.

Subjects were lit with a Simpact Icarus light (The new EFFI-Spot light is now recommended). It is necessary to adjust the HDR in all the images in order to increase the level of exposure. As with any type of macro filming, the depth of focus is very narrow.

(The banner image at the top of the page shows a close up of a screw thread)

Example 1 – Metal Rule

The field of view (FOV) at minimum zoom is ~17.5mm. Zoom the lens in to its maximum point, the FOV becomes ~1.4mm. The black lines you see in the image on the right show the 1mm divisions on the metal rule.

Example 2 – Hypodermic Needle

This image shows a 0.7mm hypodermic needle at minimum and maximum zoom.

The types of applications that require this amount of magnification and frame rate recording are likely to be very specialised e.g. the movement of micro particles, inkjets, high frequency vibrations. The Navitar 12x zoom lens with the NOVA S12 or Photron SAX2 mono camera provide a workable system for filming macro subjects. This combination has already been used to study jets of adhesive, fine sprays, particles suspended in a fluid and the moving parts within various medical devices.

The lens is free to hire subject to a standard weekly dry hire rental of any the Slowmo range of Photron cameras.

Images showing the Photron SAX2 mono high speed camera with Navitar zoom lens in operation.