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Microscope camera is a crucially important module of any image analysis system for microscopic research. Camera selection depends on your application. Always feel free to contact us for professional help! To choose the right camera for your microscope image analysis task and complete a useful and universal workstation at reasonable price, consider the following:
CMOS or CCD
CCDs (Charge-Coupled Device) have been ruling the world of camera sensors since 1970. Several years ago, we would have recommended CCDs as the most sensitive and high quality solution for microscope camera. However, in the recent years, the CMOS technology (Complementary Metal–Oxide–Semiconductors) has made several revolutionary steps increasing image quality, sensitivity, dynamic range, signal to noise ratio and, especially, frame rate. Due to technological specialties of CMOS sensor production, they are also much cheaper then CCDs. Therefore, currently, we recommend using CMOS sensors for all microscopy imaging tasks, even including low light fluorescence.
Color or Monochrome Camera
If color does not play any role in detection of objects of your microscopic examination and/or object classification, always choose monochrome camera, since monochrome and color versions of the same sensor have different resolution and sensitivity.
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Color versions of the most available image sensors are built by overlaying an array of color filters (red, green, blue) on monochrome sensor. This filter array is called Bayer Filter mosaic (named after its inventor Bryce Bayer). The actual color of every camera pixel is then interpolated by considering the information from the pixels in its neighborhood. This process is called demosaicing or debayering. This means, some camera pixels are used to obtain green color, some for red, some for blue and then the real color is reconstructed: |
There are 2 times more green filters than other colros, since human eye resolution is higher in green region of the spectrum. Due to this interpolation algorithm, the actual reolution of a color camer is a bit less than that of the monochrome camera based on the same sensor, because every value from a monochrome sensor directly becomse the pixel of the image. The image from a sensor with color filters array (even if it has a greyscale mode) will be providing less contrasted details, a bit bulrred as compared to the image from the same sensor without color filter. Additionally, the color filters absorb some light, which is the reason why monochrome sensors are more sensitive than color versions. There are some different ways to receive color on camera: using 3 sensors, one for every color plane, or subsequent exchange of filters with the same color. However, such technologies have no wide use in camera production because of high costs and/or very low frame rate.
For applications in microscopy whith low light conditions, especially, fluorescence microscopy, we recommend using monochrome versions of the cameras. MMC FISH software module will aid you in assigning pseudocolor to combined monochrome images.
Camera Resolution
The term «digital camera resolution» is often used to describe the overall number of camera sensor pixels: resolution 5 Mp. But this is not exactly correct because the real resolution on object, which is the number of pixels describing the objects, depends on pixel size and not on the overall number of pixels.
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