Sensor size and Pixel Size
Sensor size refers to the size of the chip inside of the camera. Your sensor size needs will vary based on your application, often than not this number is over looked and we look only at the mega pixel value of a camera, this can lead to lower quality images despite the high pixel count.
A Small sensor size in microscopy terms is usually seen to be around under half an inch. The smaller the sensor usually the more budget the camera (this may not always be the case).
A Larger sensor size (assuming the pixel count is the same) will give better low light imaging, such as florescence as the pixel size itself will be greater. A larger pixel size will give ultimately more light giving an image with lower noise.
Does a larger sensor size mean a higher pixel count?
No, the two are often associated. However, it is not always the case. For example if we use our smartphone camera we can get a 20 mega pixel image but certainly this won’t be a 1 inch chip. This is due to the pixel size, a phone will typically have a much lower pixel size to save space compared with a microscope camera that will increase pixel size to allow more light.
Software & Processing
You may think that a camera is the only factor to consider when buying a camera. But here at Indigo we have learnt over the years that two cameras may be practically identical on paper but produce vastly different results.
Why? Well often than not a cameras raw image to the user will be not be the end result the user sees. This is down to the processing (often done behind the scenes in the driver) with HDR filters and other forms of compensation you will see a completely different image. This makes choosing the correct manufacturer an important choice, two cameras may be the same in price and specifications but with completely different results. Here at Indigo we offer Jenoptik and Zeiss cameras which we have tested and stand by the result.
Manufactures will source their camera chips at varying quality’s. Often than not the most expensive camera brands will have stricter QC on issues such as dead pixels. Ultimately giving you a better experience.
This may sound obvious but picking a camera with a sensible interface is important. For example, older cameras use now redundant interfaces meaning users are forced to upgrade. However, customers who chose connections such as USB and Ethernet are continuing to use their cameras from the same time period.
A safe bet will be USB as this can only evolve to faster speeds and ensure backwards compatibility.
Most cameras brands will use binning to reduce large pixel images down to usable resolutions. Binning, in camera terms, is the process of grouping pixels together to produce a lower resolution.
Before purchasing a camera, be sure to check out the resolutions available and make sure this meets your needs. Too higher resolutions and lack of binning will give most people a headache in image processing. Too lower resolution and you will see the pixels at a lower zoom rate when zooming into your image.
This number can be important when selecting a camera, it ultimately gives you a look into how efficient the sensor is in response to light.
Quantum efficiency is defined by assessing the sensors ability to convert each incoming photon’s into electrons.
These graphs are important for low level fluorescent microscopy. For low level fluorescence you will want a camera with an overall higher QE.
Colour or monochrome
For most applications a colour camera is preferred. However, for fluorescence microscopy or low light applications a monochrome camera may be considered.
Colour cameras will only capture a third of incoming light as the light is filtered by the sensor. Meaning monochrome sensor pixels will receive up to 3x more light.
What does this mean for my resultant image?
The resultant noise at the same gain levels will be noticeably smaller. Giving you a cleaner image.
Because I have a third of the sensor pixels does that make it cheaper?
We get your thinking but… no. The cameras are manufactured and sold with these benefits in mind. Often than not a monochrome camera can be more expensive than its colour equivalent.
Thread Connector Size and Couplers
Thread size is important on a camera. With some manufacturers such as Jenoptik producing a whole range with the same thread (C Mount), to make it easier on choosing a camera. Sometimes this isn’t possible. Some chips go over 1 inch and require bigger adapters to fit the chip size.
With different chip sizes a different coupler will be needed to ensure the whole field remains in the camera. Don’t worry we can work this out for you.
Often than not now all sensors are back illuminated, this concept involves altering the standard manufacturing process of a front illuminated sensor.
We won’t go into specifics as this will not help with choosing your camera, but just know when choosing a camera your best bet is to choose a back illuminated sensor to increase light throughput.
Can a DSLR be used on my setup
This is a common question we get here at Indigo and on the surface of it, yes you can.
However, this is not designed specifically for a microscope and you will have to find couplers and optics to fit your dslr.
As well as this microscope cameras often offer the best specifications for microscope applications, not to mention much needed software for producing high contrast, high refresh image rates to your screen.
So while the basic answer is yes, the cost of a microscope camera will pay off not only on the results but of ease of use and flexibility throughout its lifetime.