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Compact cameras and camcorders on the microscope : Digital single lens reflex cameras and mirrorless system cameras are simply better!  

Compact cameras and camcorders are among the most popular types of digital cameras due to their convenient size, ease of operation and the many applications they offer. As they are primarily designed for capturing objects, landscapes and people, these cameras are not the best choice for photomicrography and macrophotography.

Compact cameras (see image on the left) have one thing in common: the lens unit is fixed within the camera body and cannot be removed. For applications involving microscopy and macroscopy, however, the camera lens is not only unneeded, but even somewhat of a hindrance.

In the case of digital single lens reflex cameras (DSLRs, see image on the right), the lens is connected to the camera body by a bayonet fitting. That design is beneficial for microscopy applications because the microscope’s adapter, which performs the camera’s mechanical and optical adjustments, can project the image directly to the camera’s sensor.

At present, two different types of lens designs are used in compact cameras:

1. Lenses that are housed entirely within the camera body and do not need to be extended for use. This approach is used mainly in ultra-compact cameras, which are extremely small in size, and also in camcorders. 
   
   As the zoom factor in these cameras is not particularly large (the zoom system contains only a few lens elements), they are the most suitable type of compact cameras for microscopy applications. Some of these cameras and camcorders have a filter thread at the front of the camera body which makes it quite easy to attach the camera/camcorder firmly to the microscope (see image on the left). If there is no filter thread, the camera/camcorder can be mounted to the microscope using an angle bracket as a makeshift connector (see image on the right). 
   
    
2. Compact cameras equipped with extendable lenses that offer greater zoom factors. These cameras have wide-aperture lenses with a large front element. At the long end of the zoom range, the lens protrudes several centimetres from the front of the camera. Despite their high quality, these camera models are unfortunately not well suited for microscopy applications. The mechanical attachment of the camera to the microscope is extremely difficult and can never be done perfectly. By extension, if the camera is not connected firmly to the adapter, there are risks of motion blurring, inexact optical axis alignment and stray light entering the photo tube.

In fact, modern zoom lenses represent the biggest problem when using compact cameras or camcorders on a microscope:

• Due to increasingly complex lenses, the zoom range of compact cameras is constantly being expanded. Every lens unit of this type contains a large number of spherical and aspherical lens elements. As a result, when such lenses are used with a microscope, they cause a significant deterioration in image quality, such as poor focus at the edge of the image, distortions, chromatic aberrations, washed out colours and vignetting (peripheral darkening). Ideally, the lens unit should be removed completely, but unfortunately, in the case of most compact cameras this is not possible without destroying the camera body.
• Furthermore, incorrect autofocus settings or the application of erroneous focus to an object other than the target often causes blurred images. It is not always easy to “outsmart” the automatic features of such lenses. 
• With a fixed lens, on the other hand, the field of view (FoV) cannot be adjusted optimally. As with all compact cameras, microscopic images must be taken at high zoom settings, i.e. at tele setting, and in extreme cases even in digital zoom mode. However, the higher the zoom level, the smaller the image section that will be produced. In many cases, the surface area of the captured image ranges from just 25%–40% of the image visible through the eyepiece. 

Slight vignetting may sometimes occur along the edge of the image, and those undesirable black edges can be removed only by using the digital zoom or image editing applications.

The technology used in compact cameras cannot compete with that of DSLRs. Compact cameras have much smaller image sensors that provide weaker signal-to-noise ratios, lower depths of colour, resolution and dynamics, and fewer options for exposure time settings. These shortcomings result in a significantly inferior image quality.

For photomicrography and macrophotography applications, we recommend controlling the camera remotely via PC or Mac. This not only prevents the motion blurs caused by pressing the camera’s shutter release button, but it also permits the camera to be navigated on the screen and enables Live View output to a larger monitor. The Live View magnification function included in most software packages offers many additional advantages. For instance, images can be saved directly to the PC’s hard drive, a function not typically possible with compact cameras. Also, when a compact camera is used for photomicrography or macrophotography applications, the use of its small, integrated screen for camera operations is quite inconvenient. 

Thus, the primary function behind the use of microscope adapters for compact cameras is to mitigate the negative characteristics of the camera’s lens unit and project the microscopic image onto the sensor. This works quite well with some cameras but much less so with others.

Notably, the performance gap between compact cameras and DSLRs has continued to increase in recent years.

Although camera prices are continuing to fall (especially among compact cameras), new high performance technologies that improve image quality are typically available in only the top range of DSLR models. However, new entry-level models that start at EUR 300.00, or used DSLRs manufactured after 2007 (such as the Canon EOS 1000D or EOS 1200D) are also very well suited for microscopy. A list of digital cameras ranked according to their suitability for microscopy applications can be found on our website at: Which digital camera works best with microscopes?

Conclusion: 

In the professional field, we would advise against the use of compact cameras for photomicrography. Those with a serious interest in microscope photography should not cut corners when it comes to the camera they choose. DSLR cameras and system cameras are far superior to compact cameras when photomicrography applications are concerned. For this reason, we recommend using modern DSLR and system cameras. We offer a wide range of products that facilitate connecting these cameras to optical instruments.

22.10.2015