Since the inception of digital microscopy, scientific grade CCD cameras have been the gold standard for imaging due to their sensitivity, linear response to light and low noise. However, many of these live cell mechanisms occur on short time scales and emit low luminescence signals, making imaging with sufficient signal-to-noise and temporal and spatial resolution difficult for slower CCD cameras.
Solution: sCMOS technology and its unique sensor architecture deliver a combination of low electronic noise that nearly triples the signal to noise ratio and image contrast of CCD cameras with up to ten times the frame rate potential, making it possible to collect high quality images with shorter exposure times. While early CMOS devices suffered with image quality issues, steady improvements in pixel readout circuitry and improved data handling have largely erased these deficiencies. With advanced sCMOS technology, researchers now have access to the speed needed to resolve time-sensitive cellular events, the sensitivity required to resolve low luminescence signals due to short exposures, and the resolution to resolve small cell structures.
The introduction of QImaging’s optiMOS™ sCMOS camera, is a recent example of a product that now puts this sCMOS technology within the reach of more life scientists. It’s an attractive alternative to traditional CCD cameras, capturing rapid cellular dynamics across a larger field of view without sacrificing sensitivity. At the same time, it’s more affordable and avoids the complex data management issues of other sCMOS cameras.
With a frame rate of 100 frames per second—ten times the time resolution of CCD cameras—the optiMOS captures high-speed cellular events, including vesicle formation, protein transport, and calcium wave propagations. The camera’s < 2e- of low electronic read noise nearly triples signal to noise ratio and image contrast, making it possible to collect high quality images and preserve cell vitality with shorter exposure times. Additionally, the camera’s 45 percent larger field of view (FOV) compared to standard CCD cameras allows users to acquire more data per image.
Also, in a practical nod to the enormous amount of data output by sCMOS cameras, the optiMOS eliminates excess pixels found in larger sensors that overfill the microscope’s field of view, saving time during imaging processing and further optimizing the user experience and budget. While many researchers are turning to sCMOS cameras because of their low noise and speed, they don’t realize the difficulties involved in managing sCMOS data. Most sCMOS cameras require complex computer frame grabber configurations and multiple expensive SSD hard drives in a RAID configuration to handle the overwhelming data rates and subsequent massive data volumes. Thanks to the data rate of the camera and optimized high-speed PCIe interface, optiMOS eliminates these two costly elements.
While there are several instances when using an sCMOS camera is preferred, knowing exactly when to use sCMOS over CCD depends on the application and most importantly exposure time. CCD cameras provide highly quantitative data and excel in applications like chemiluminescence with long exposure times. As not all CCD and sCMOS cameras are created equal, it’s important to factor not only frame rates, but data complexity, integration and total cost of ownership when choosing a camera best suited for you.