MICROSCOPY/ADVANCED BIOIMAGING: Life in HD: A new view of microscopic imaging

Although most people now expect high-definition (HD) from televisions, biologists still find HD images rather new in microscopy. In many cases, getting the clearest images to share or study requires an HD camera or monitor. The market now offers a number of options for HD microscopy, including new offerings from Lumenera Corporation (Ottawa, Canada), Martin Microscope Company (Easley, SC), and Olympus America (Center Valley, PA).

For a microscopist, the tools for capturing an image change fast these days. "About 10 years ago, biologists used lower-resolution digital cameras with microscopy," says Ian Holland, technical assistance center member at Lumenera. "Then demand grew to 2, 3, 5, 8, 11 Mpixels and more. All of the manufacturers followed the consumer market of more megapixels on a camera."

When asked where biologists want HD cameras or monitors for microscopy, Paul Jantzen, marketing manager for core microscopy and research imaging at Olympus America, says, "For live applications where they want to project an image on a large screen for multiple people to view."

Inspiration for adaptation

In 2004, Robert H. Martin, Jr., owner of Martin Microscope Company, helped researchers at the Smoky Mountains National Park (Gatlinburg, TN) make a video series for middle school students. "We'd been making adapters for consumer digital cameras to go on microscopes since 1999, and they wanted to take a video of microorganisms swimming," says Martin. "We used one of our MM99 still-camera adapters on a camcorder, and it worked really well."

About a year later, the same researchers wanted to try the adapter on an HD camcorder for their own use. "It was amazingly clear," Martin says, "better video output than we'd seen." That started Martin's work in HD imaging.

Martin expected to soon face competition. He says, "I thought it would only be a year or two before someone made a microscope camera with HD output, but it took quite a while for that." Although some microscope cameras now include an HD output, Martin adds, "We still haven't seen one with quite as good live output or quite as versatile as ours. The primary advantages of using a consumer HD camcorder for microscopy are relatively low price, the ability to actually record both digital still images and video, and the ability to use the camera without the microscope as a normal HD camcorder."

Martin currently offers an HD system, the MCV52 1080p High Definition Microscopy Package, that includes a Canon Vixia HF M52 1080p HD Camcorder and the Martin MM99-43 adapter (see Fig. 1). "We can also provide complete systems including a microscope, HD camera and adapter, and even an HD monitor," Martin says.

Most of the time, Martin finds that schools use this HD video system for live classroom viewing. "We've sold some to high schools," Martin says, "but mostly colleges and universities—quite often smaller colleges—buy them because they work extremely well, yet are affordable." Many customers, though, use this system's 30 frames per second (fps) for live-video analysis in research. Moreover, Martin says, "The pathology department at Duke University uses our system in their conference room for group consultations."

Balancing resolution and speed

Although more megapixels provide higher resolution, more pixels also re-quire more time for image acquisition. So the frame rate tends to go down as the number of megapixels goes up. In many biological situations, researchers prefer a balance between resolution and speed.

"In the majority of digital-camera applications in the life sciences—from pathology to marine biology—researchers find that 2 Mpixel cameras seem to satisfy the best of both worlds: reasonably fast frame rates and reasonably high-quality images," says Ian Holland, senior applications engineer at Lumenera Corporation.

The Lumenera INFINITYHD is making its mark for its fast frame rate, clear image quality, and superior color reproduction. It's a 1080p60, CMOS-based camera that can capture 60 fps. "This camera was purpose-built for applications with a direct connection to an HD monitor," says Shari Anne Bordeleau, director of channel business development at Lumenera Corporation. In addition, this camera has a built-in auto-intensity algorithm which makes the camera respond to changes in light levels as magnification is adjusted. "Feedback from end-users is that this feature, along with the three on-camera buttons, makes the camera simple to use," Bordeleau says.

When asked who makes up the users for this camera, Bordeleau says, "anyone doing live imaging where color reproduction and fast response is critical." More specific examples, says Holland, include "hospital review boards, teaching environments and surgical suites." He also notes some research applications, such as "looking at live cells in embryonic research."

Consumer to scientist

Beyond that direct connection to a monitor, these cameras benefit from another link: technology flowing from the consumer market to the research arena. "The higher definition of these cameras is built using proprietary Olympus color technology," Jantzen says, "and this technology came from the consumer-camera division." He adds, "It leverages our great experience in consumer cameras, and it provides extremely accurate, reproducible color in our images." It turns out that some colors can be captured more easily than others. "One of the most difficult colors is purple," Jantzen says, "because it's at the end of the spectrum, where silicon is not efficient." Nonetheless, these Olympus cameras even reproduce purples with great accuracy.

Beyond reproducing colors precisely, these cameras also give a steadier image when something under the microscope moves. This camera's so-called progressive scan technology, says Jantzen, "provides a smoother readout. So you can have a specimen on the microscope's stage, move the stage and not see blurring in an image projected to a monitor." The traditional approach, called interlaced scanning, reads out rows of pixels alternatively, which can blur the image during movement.

Having spent many, many hours teaching procedures to students and moving back and forth to let them see what's going on under the microscope, I completely appreciate the value of these HD devices to share a clear view. Likewise, from a purely research perspective, I can envision sitting back in a lab and just watching activity under a microscope. It would be great to get the clear picture and just watch something taking place in real time under the objective. You just never know what you might see.