Breckland Scientific 2023 Catalogue

Microscopes

How to choose your Microscope... Choosing the right microscope can be daunting and the terminology confusing. In order to help you we have rearranged our microscope section by feature, grouping similar microscopes from different manufacturers together for easy comparison. Once you have settled on the features you want then it is simply a matter of choosing a microscope that you like the look of and that feels natural to use as well as fitting within your budget. How old are your students? If you are buying microscopes that are going to be used only by younger students , consider buying a three-quarter size microscope. Three-quarter size microscopes tend to be lighter and easier for smaller hands. All the three-quarter size microscopes in this catalogue are monocular, we are happy to quote on binocular versions but have found that younger pupils often struggle adjusting the interpupillary distance of the eyepieces and find a monocular model far easier to use. What will your students be studying? Consider what it is your students will be studying, if this is larger objects such as flowers, insects, rocks etc then you want a low-powered stereo microscope . Stereo microscopes are, by definition, binocular and give a three-dimensional image. If your students are looking at microscope slides, then you need a biological (compound) microscope. For most school applications, a magnification of 400x is enough , however if your students want to look at bacteria you will need a magnification of 1000x . Microscopes which offer 1000x magnification should also have a 1.2NA or 1.25NA condenser to achieve the required resolution. We would suggest that you buy a microscope with a mechanical stage if you wish to use a magnification of 1000x. What sort of illumination? Most of the microscopes in this catalogue have LED illumination , this provides a cool, even, white light with the added advantage that the LEDs rarely need replacing. Halogen gives a very bright, white light though the bulbs tend to get hot. The light from tungsten bulbs can be a little yellow and as with halogen they give off a lot of heat. Which brand? We carry four different brands of microscope: Kern, Motic, Swift, and Optika. Several models across the brands have the same features, when choosing between these consider the quality of the optics and the quality of the construction, you may be looking for a low-cost microscope for light use by older students or a sturdy model to withstand rougher treatment by younger children with less developed precision motor skills. Kern - Kern are a German company synonymous with quality balances, This is their first foray into the microscope market with a simple but elegent design. German engineering and quality will ensure a durable and reliable microscope range. Motic - Motic are the market leader in secondary education, known for their sturdy construction, longevity and quality optics, you will not be disappointed with a Motic microscope. Optika - The Optika B-155 and B-190 microscopes have been tested at a magnification of 1000x using water rather than oil and the resulting images are pretty good! (See images opposite) Swift - The Swift brand is owned by Motic which is a perfect fit for both optical and build quality. These microscopes are as student-proof as you can get. A word about lenses. The resolution of your microscope is limited by the power of the objective lens, the eyepiece lens merely magnifies the image but does not add detail. Most educational microscopes have achromatic lenses, these correct for colour aberrations and have about 60 to 65% of the field of view in sharp focus, any aberrations will be in the outer 35 to 40% of the field of view. Most of us will not even notice this loss of image quality. A semi-plan lens will have approximately 80% of the field of view in sharp focus with any aberrations appearing in the outer 20%. However not all lenses are created equal and the semi-plan lens from one microscope may be pretty much the same as the achromatic lens from another. Unsurprisingly you pay more for lenses with better clarity, colour correction and fewer optical aberrations. Although much of the value of a microscope is in the quality of the optics, and this is the most important factor, there are other features to consider: Build: Do you prefer a traditional design or a more modern looking microscope? A solidly built microscope or a lighter more transportable one? Comfort and ease of use: Do you prefer binocular or monocular? Do you find using coaxial or separate coarse and fine focusing more natural? Do you value the precise control which you get with a mechanical stage or do you find it easier to move the slide manually?

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We can help you to decide which features are important to you and to select the microscope that is right for your school.

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Still unsure which microscope to chose? Contact your Sales Support Manager for more bespoke advice about which microscope will best suit you. Your Sales Support Manager can also arrange on site demonstrations! See inside front cover for contact details.

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www.brecklandscientific.co.uk T: 01785 227227 | sales@brec landscientific.co.uk | F: 01785 227444