Wednesday March 07, 2001
The Eclipse 800 Microscope is a premier member of Nikon’s advanced research microscope line. Although I generally use this microscope to detect GFP-tagged proteins and analyze their localization within a cell, this microscope can be used for a number of different observation techniques and allows one to record the images easily.
The E800 series incorporates Nikon’s CFI60 optical system that (according to them) alleviates the limitations of conventional optics, allowing for very long working distances (for a tutorial on Nikon’s CFI60 Optical System, click here). This system corrects chromatic aberrations over the entire field of view, generating a very sharp, clear image over the broadest magnification range. One can also put in a broad range of accessories without affecting optical quality. The microscope is designed so that the scientist can work with ease, especially in the dark, requiring little movement to operate the control knobs and handles.
The CFI60 Optical System offers a 60mm objective parfocal distance, a 25mm objective thread size and a standard 25mm field of view all of which combine to provide a higher optical quality. The net result of these features produce 1) a long working distance between the objective lens and the cover glass (up to 210 micrometers) and high numerical aperture (of 1.4) objectives, which generates excellent resolution, very good image capability and more room to handle thicker specimens, 2) a very wide magnification range without comprising sharpness or contrast, 3) 0.5X objectives, which allows for actual size documentation, not just portions of the specimen (this 0.5X objective can be installed with the other objectives on the same nosepiece, which is very convenient), 4) longer parallel optical paths, allowing insertion of three levels of modules (Epi-fluorescence, macro slider and accessory modules) 5) unequaled fluorescence observation capability with wide-field image flatness and higher UV light transmission producing very high signal-to-noise ratios and very high contrast images against a dark background under fluorescence, and 6) universal-type objectives, allowing one to utilize a wide range of techniques, such as phase contrast, brightfield, dark-field, Nomarski DIC, polarized light and fluorescence eliminating the need for different objectives.
Perhaps one of the biggest advantages of the E800 microscope is the system flexibility. Because the CFI60 Optical System incorporates parallel light beams, this allows one to easily upgrade the microscope by installing different accessory modules (such as a beamsplitter module, Epi-fluorescence attachment or a magnification –changing module) without affecting optical performance. In addition, the E800 has some nice features such as a microscope slider that can handle up to 5 filter blocks and a magnification module that allows intermediate magnification changes. Also, the photo system head can take two 35mm cameras (one large-format camera and one CCTV camera), allowing one to store and document images on a computer connected to the microscope. Other physical features that make the use of the E800 microscope convenient are 1) low position of the stage, making changing of specimen or slides easy, 2) wide stage travel or stage rotation angle, 3) ample space around the stage, allowing one to manipulate the nosepiece and change specimen without hindrance and 4) the coarse/fine focus control knobs and the stage handles are located equidistant to the operator, which permits one to operate the stage and focusing with one hand. Our E800 microscope is connected to a Cooled CCD Video Imaging System that allows us to detect low-level fluorescence with high contrast and brightness.
Like all other large, delicate machines, one must take extreme care in the use and maintaining of this microscope. It took at least a week to install the microscope with its accessories and to become fully cognizant of all the features of the microscope system. The other disadvantage is that the lamp and the lamphouse at the lower back of the microscope (it is somewhat near the filter insertion/removal lever) becomes very hot during use, so one must avoid getting their hand close to that area of the microscope. In addition, this microscope (with its accessories) can take up a lot of space, so one must be sure to allocate a sizeable space in the lab to accommodate the whole system.
Hee Chul Lee
Graduate Student
Dept. of Biochemistry
NYU School of Medicine