1. How do I choose a Microscope Eyepiece camera?
Types of Cameras
There are a variety of different digital eyepiece cameras available designed specifically for use with standard (monocular, binocular, or trinocular) microscopes. The BigCatch "EM" series are compatible with both the 23mm and 30mm diameter ocular tubes found on most standard microscopes. The installation of the eyepiece camera is the same for both versions and requires the removal of the microscope eyepiece from one of the ocular tubes and simply inserting the eyepiece camera. Certain trinocular version microscopes may require a special C-mount adaptor which comes with the EM(C) model C-Mount eyepiece cameras.
You need to consider certain performance features of the digital camera and determine if they meet your requirements. You also need to ensure that your computer and operating system are compatible with the eyepiece digital camera software. Other things to consider;
* Determine the desired camera field of view.
* The camera must match the objective lens par-focalization.
* The camera must offer a sharp and clear image in true color.
* The camera should offer video imaging at speeds of 15-30 frames /sec.
Quality of sensor
There are Four types of sensors that we currently carry. Super Color CCD, CCD, Enhanced Color CMOS, and CMOS
Each one has certain advantages and disadvantages depending on application.
The CMOS sensor (Model # : EM-XXX) offers basic performance.
The Enhanced Color CMOS sensor (Model # : EM-X10) is an improved CMOS with great color quality & refresh rate.
The CCD sensor (Model # : EM-CXXX) has a fast transfer rate and also is great for florescent or darker applications.
The Super Color HP CCD (Model # : EM-XXXF) is an improved CCD that has excellent color quality with a refresh rate comparable to the CCD.
Finally, you should consider the software supplied with the camera. Some other cameras come without imaging software. Some come with basic imaging software with simple photo and video capturing functions only. Some users require enhanced software features with measurement and other image processing capabilities such as the "ScopePhoto" software included with the "EM" series eyepiece cameras.
Types of Microscopes
A binocular is a microscope with a head that has two eyepiece lens. Nowadays, binocular is typically used to refer to compound or high power microscopes where the two eyepieces view through a single objective lens. A stereo (or low power microscope) may also have two eyepieces, but since each eyepiece views through a separate objective lens, the specimen appears in stereo (3-Dimensional).
A trinocular port on a microscope is the third port. It is used for microphotography and video applications. This port is where cameras are attached, so the viewing port for the human eyes is left open for viewing the specimen. This dedicated port is typically located on the top of the microscope head. However, on some models, it can be located horizontal and off to the side.
BigCatch eyepiece cameras are capable of adapting to binocular and trinocular microscopes. BigCatch c-mount cameras are designed specifically for trinocular microscopes.
2. Field of View
Below are several example configurations, along with an estimate of the human eye field of view (FOV) for comparison.
|Model||Sensor Size||FOV @ 64x (16x4)||Objecteve @ 64x||FOV @ 160x (16x10)||Objective @ 160x|
|Human Eye||---||EST 3.3mm x 3.3mm||EST. 1.3mm x 1.3mm|
|EM-130||1/3||3.4mm x 2.6mm||90%||1.34mm x 1.06mm||92%|
|EM-310||1/2||2.77mm x 2.07mm||73%|
|EM-510||1/2.5||2.4mm x 1.8mm||63%||0.93mm x 0.69mm||62%|
|Model||Sensor Size||FOV @ 64x (16x4)||Objecteve @ 64x||FOV @ 160x (16x10)||Objective @ 160x|
|Human Eye||---||EST 3.3mm x 3.3mm|
|EM-130||1/3||2.9mm x 2.3mm||86%||---||---|
|EM-310||1/2||3.2mm x 2.4mm||92%||---||---|
|EM-510||1/2.5||2.0mm x 1.5mm||58%||---||---|
3. What are the system requirements for my computer?
CPU: Equal to Intel Core2 2.8GHz or Higher
Microsoft® Windows® XP / Vista / 7 (32 & 64 bit)
Memory: 2GB or More
Hi-speed USB 2.0Port
16-bit color display monitor or higher
21″ display monitor or higher (Recommended)
4. How to improve the image color quality for best results?
One-push White Balance
Setup > Video Source Properties > One-push
To get the most precise and consistent white balance results, adjust the white balance rectangle to a background region (where the color temperature of the illumination is reflected) and then click the One Push button. The size of the rectangle does not matter, but the area contained within the rectangle must be white.
5. About CCD Sensors
Basic CCD Characteristics
A CCD chip is an array of light-sensitive elements and very small electronic capacitors. These capacitors are charged by the electrons generated by the light. Each light element (photon), that reaches the CCD array's atoms displaces some electrons. This displacement provides the current source. These current sources are localized in small delimited areas (the capacitors) called pixels. Common CCD chips are composed of thousands or millions of pixels.
A single Output
The capacitors are discharged in lines and control gates allow the transfer of one pixel line into the next one. The last line of the array is transferred into a horizontal shift register. This shift register allows the transfer of one pixel to the next one, and the last pixel of this horizontal register is connected to the output gate.
Taking a Picture
Clean the CCD array by reading the picture. Wait for a defined time ( the exposure time) to allow the light to charge the capacitors. The output gate of the CCD array can either be connected to an analogue or to a digital converter in order to digitize the picture, or it can provide a standard video signal if the clock's timing is according to the video norms. If the image is digitized, it will be easy to store it in a computer memory. So, its processing will be easy to perform.
6. About CMOS Sensors
Standard Fabrication Lowers Costs and Enables On-Chip Integration
CCD sensors rely on specialized fabrication that requires dedicated—and costly—manufacturing processes. In contrast, CMOS image sensors can be made at standard manufacturing facilities that produce 90% of all semiconductor chips, from powerful microprocessors to RAM and ROM memory chips. This standardization results in economies of scale and leads to ongoing process-line improvements. CMOS processes, moreover, enable very large scale integration (VLSI), and this is used by our “active-pixel” architectures to incorporate all necessary camera functions onto one chip. Such integration creates a compact camera system which is more reliable and removes the need for peripheral support chip packaging and assembly, further reducing the cost.
Low Power Usage Extends Battery Life
Active-pixel sensor architectures consume much less power—up to 100x less power—than their CCD counterparts. This is a great advantage in battery-dependent portable applications, such as laptop computers, hand-held scanners, and video cellphones. CCD systems, on the other hand, tend to be inherently power hungry. This is because CCDs are essentially capacitive devices, needing external control signals and large clock swings (5–15 volts) to achieve acceptable charge transfer efficiencies. Their off-chip support circuitry dissipates a significant amount of power. CCD systems require numerous power supplies and voltage regulators for operation, whereas active-pixel sensors use a single 5-volt (or 3.3-volt) supply, reducing power-supply inefficiency. A CCD system typically requires 2–5 watts (digital output), compared to 20–50 milliwatts for the same pixel throughput using an active-pixel system. For example, a CMOS digital camera system operating from a NiCd camcorder battery could operate for a week, while a CCD arrangement would drain the battery in a few hours.
Random Access to Pixel Regions of Interest Adds Flexibility
In CMOS active-pixel image sensors, both the photodetector and the readout amplifier are part of each pixel. This allows the integrated charge to be converted into a voltage inside the pixel, which can then be read out over X-Y wires (instead of using a charge domain shift register, as in CCDs). This column and row addressability, similar to common DRAM, allows for window-of-interest readout (windowing), which can be utilized for on-chip electronic pan, tilt, and zoom. Windowing provides much added flexibility in applications that need image compression, motion detection, or target tracking.
No Artifacts, Smear, or Blooming Means Higher-Quality Images
With our active-pixel architectures, the RMS input-referred noise is comparable to very high-end (and expensive) CCDs. Both technologies provide excellent imagery compared with other CMOS image sensors. Our active-pixel architectures use intra-pixel amplification in conjunction with both temporal and fixed-pattern noise suppression circuitry (i.e., correlated double sampling), which produces exceptional imagery in terms of dynamic range (a wide ~75 dB) and noise (a low ~15 e-RMS noise floor), with low fixed-pattern noise (<0.15% sat). Our active-pixel sensors achieve a quantum efficiency (sensitivity) that is comparable to high-end CCDs, but, unlike CCDs, they are not prone to column streaking due to blooming pixels. This is because CCDs rely on charge domain shift registers that can leak charge to adjacent pixels when the CCD register overflows, causing bright lights to “bloom,” leading to unwanted streaks in the image. In our active-pixel architectures, the signal charge is converted to a voltage inside the pixel and read out over the column bus, as in a DRAM. Our sensors have built-in anti-blooming protection in each pixel, so that there is no blooming. Smear, caused by charge transfer in a CCD under illumination, is also avoided.
Intra-Pixel Amplification and On-Chip ADC Produce Faster Frame Rates
CMOS active-pixel designs are inherently fast, which is a particular advantage in machine-vision and motion-analysis applications. Active pixels can drive an image array’s column buses at greater speeds than is possible on passive-pixel CMOS sensors or CCDs, and on-chip analog-to-digital conversion (ADC) it eases the driving of high-speed signals off-chip. A separate benefit of on-chip ADCs is the output signal’s low sensitivity to pick-up or crosstalk. This facilitates computer and digital-controller interfacing while adding to the system’s robustness.
On-Chip Integrated Circuitry Enables “Smart” Camera Functions
CMOS active-pixel architectures allow signal processing to be integrated on-chip. Beyond the standard camera functions—AGC, auto-exposure control, etc.—many higher-level DSP functions can be realized. These include anti-jitter (image stabilization) for camcorders, image compression (before and after readout), color encoding, computer database interface circuits, multi-resolution imaging, motion tracking for perimeter surveillance (“smart image sensing”), video conferencing, and wireless control.