Microscope Service Techniques

December 01, 2010

Microscope Service Techniques

Microscope services are depend on kinds of microscopes and kinds of damages. We already known if microscope is consist of mechanical and optical parts like I was told in my previous post What is Microscope?”. Which parts of microscope that often damage? So that can disturb the microscope parts functions optimally. Here we will learn how to service and repair microscope mechanical parts and optical parts too. The procedures below will effect to service time will going to do.
  1. Take apart all optical components like lenses, condenser or/and diaphragm, mirror.  ( see picture below).
  2. Reset and readjust the troubled mechanical parts such as loosed ocular tube (for light microscope), troubled coarse or fine adjustment knob.
  3. Cleansing optical parts such as lenses, condenser or mirror (light reflector).
  4. Cleansing body parts with glosser or other cleanser
  5. Setting optical parts to mechanical parts
  6. Checking with preparation slide
  7. Labeling with after service label
  8. Covering with plastic cover to prevent dust from the air.

How often the microscope needs to service?
When we have to service our microscope?
How long period of microscope service?

We agreed if microscope is useful for biological learning (in school from elementary to college) as well as in many institutions like health laboratory, hospital, etc. Microscope will optimally useful when each function works well. To keep optimal performance of microscope, we should know the lacking of our microscope. That’s why we must service microscope? , and which components of microscope that often troubled, and what we need to attention if our microscope has been serviced on that articles I already told. 

Several things that we need to pay attention, related to how often microscope needs to service :
  1. Using intensity. In my workplace, department of biology education  Faculty of math and natural science education laboratories in Indonesia University of Education (laboratorium Jurdik Biologi FPMIPA UPI), we usually use microscopes in laboratory practice 32 hours per week (5 workdays) or 128 hours per month. Based on that situation, we have to check and recheck microscopes condition maximally once a month and once in every six months for comprehensive check up/service. Generally, in institutions such as middle school, microscope using is only several hours per week. For that condition we just need to check up/ service microscopes minimal once a year. Check up/ service cost will far cheaper than if we just buy the microscope and use it until broken and cannot be repair (technician restrictiveness) then buy the new one.
  2. User behavior. Even we provide best service, we can’t  prevent the microscope become troubled again if user use the microscope without responsibility or doesn’t know about microscope using well. User has to know and understand about service guarantee.
  3. Institution care and fund allocation for tools routine maintenance.

Now I will show to you about our activities on August 27th 2010, view after we service/ tune up microscopes before college season started on September 1st 2010.

Picture below are microscopes which had been serviced and ready to put in storage box equipped with “Microscope Using Monitoring paper”.

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Free article : Use Of The Microscope

September 21, 2010

The compound microscope is a precision optical instrument which has a normal life expectancy of over forty years if cared for properly. Today we hope assist you in learning to use the instrument correctly.

A. There are four general considerations one should learn before begining :

  1. Clean the lenses only with the lens tissue provided. Be sure that you do not remove any of the lenses.
  2. Attempt no repairs or adjustments, ask your instructor.
  3. Handle as carefully as you would an expensive camera. 
  4. At the close of the period you should : 
  • Know how to carry and clean the instrument
  • Be able to adjust the light correctly.
  • Be able to identify the : base, stage, diaphragm, tube, nosepiece, ocular, 10x (low power) objective, 43x (high power) objective.
  • Be able to locate an object readily and to focus the microscope correctly.
  • Be capable of determining the dimensions of an object.
  • Know how to convert milimeters (mm) to microns.  
B. Focusing the Microscope 
  1. Prepare your microscope for use by placing it in a comfortable working position not too near the edge of the table.
  2. Adjust the nosepiece so that the low power (10x) objective cliks into position over the hole in the stage.
  3. Adjust the diaphragm, using the largest hole (No. 4) in the disc.
  4. Raise the body tube so that the low power objective is about one (1) inc above the stage. Move the stage clips to one side. While observing from one side of the microscope, place the slide (with the side containing the coverslip up) on the stage of the microscope and adjust the slide so that the object to be studied is in the approximate center of hole in the stage.      :to be continue ......

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Review article : Maintenance of Microscope

August 16, 2010

Handling of microscope should be done carefully not to hit against bench, not to fall on floor, and not to dirty lenses (eyepiece and objective).


  1. How To Clean Lenses. If lenses were dirtied, your should cleans the lenses by wiping them with a sheet of lens paper or gauze soaked slightly with absolute ethyl alcohol. However, be careful not to use too much ethyl alcohol, because much alcohol must be soaked between lenses and will make eyepieces or objectives out of order.
  2. How To Clean Body. The body (Base, Arm, Knobs, Stage, and Body Tube) should be cleaned by wiping it with clean dry cloth.
  3. How To Change Halogen Lamp. When the halogen lamp blew out, you should change it fir a new one. Be careful not to touch with the halogen lamp directly, because fingerprint on the lamp must shorten the life of it. It is recommended to use gloves to change the halogen lamp.
  4. How To Repair Adjusment Knob. When the coarse adjusment knob is out of order, you should call the agency for repairing it

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Free article about Innovations in Light Microscopy

August 11, 2010


all scientific instruments, probably none has had more thought and labor devoted to its improvement than the light microscope. Its evolution over the past centuries has been driven by scientists who wish to observe and measure phenomena that were smaller, fainter, (Figure 1) and deeper inside tissue than ever before.



 An example of the images produced by today's improved microscopes is presented in Figure 1, which illustrates a digitally captured multicolor fluorescence image of tissue culture cells taken on an Eclipse E600 microscope using the CFI60 40X fluorite objective and Nikon's new DXM 1200 digital camera.
A century ago, the microscope attained the limit of resolution predicted by classical theory of the nature of light. However, more than resolution was needed to allow the microscope to examine the inner workings of living cells in real time. Techniques formerly done in very few laboratories by the supreme masters of technique are now reduced to easy, routine clinical procedures. Microscope designers, carefully listening to microscopists, have brought about tremendous innovations. This paper summarizes recent advances in microscope design and focuses on how a recently developed optical system may enhance scientific progress.
Finite versus Infinite Optical Systems
In the days when biological microscopes were relatively uncomplicated, before epifluorescence and confocal techniques, there was little need to interpose thick optical components between the objective lens and eyepiece - the interlens space. The standard 160- or 170-mm tube length, the distance between the objective mounting flange and the seat for the eyepiece, served well for this. These instruments had convergent light in the interlens space. Metallurgists and geologists needed polarized light, and before the invention of wafer-thin polarizers, this required the insertion of massive prisms and other accessories in that space. One manufacturer in the 1930s, running out of room in the standard tube and plagued with aberration correction problems due to the prisms, first attempted a version of infinity optics to get around these troubles.
The term "infinity" means that the objective lenses are designed to project their images to infinity, not to some finite distance. The infinity optical system provides a region of parallel light between objective and eyepiece. With these systems, complex optical components can be inserted in that parallel light space without either introducing optical aberrations or reducing the free working distance of objectives. The system also retains the parfocality of sets of objectives (Figure 2). Presented in Figure 2 is a conceptual diagram of CFI60 optical path. Infinity optical systems consist of an objective, a tube lens to converge the beam, and an eyepiece lens. Modules and components can be placed in the parallel optical path between the objective and tube lens to create a totally flexible system without additional relay optics. The location of the image point remains constant, both axially and laterally, as does the alignment between the objective and the tube lens.



Of course, to form an image that we can see or record, the light from infinity-type objectives must be made convergent again by a tube lens, or second objective, between the parallel light space and the eyepieces. Usually two, and in one case as many as three, major optical components can be placed in this space without diminishing performance.
Accessories and inserted components can now be designed to achieve a magnification of exactly 1X, which is valuable when comparing several optical techniques with the same specimen. For instance, when optics for epifluorescence and differential interference contrast (DIC) are installed, there is still space for a third device - a magnification changer, a teaching head, a multiport assembly for two video cameras, or a drawing head for use with a digitizing pad to trace neurons.
In the classical microscope of years ago, the lens designer had the luxury of considering the objective and eyepiece together in the correction of lens aberrations, spherical and chromatic (both axial and lateral) aberrations, coma, astigmatism, and field curvature. Lateral chromatic aberration (LCA) is also known as chromatic difference of magnification - the formation of red, green, and blue images in the same focal plane, but with each color forming a different size image.
Traditionally, LCA has been very difficult to correct, and was often left uncorrected in the objective lens, to be compensated for in the eyepiece. The varieties of optical glasses and the computational techniques available years ago were insufficient for the task of correcting LCA within the objective. The insertion of thick components in the uncorrected interlens beam would further upset optical corrections.
Even today, not all manufacturers have achieved full correction of LCA within the objective. Newer glass formulas developed by Nikon Inc. (Melville, NY) have extremely low dispersion; thus, all aberrations are corrected within the objective itself. The company introduced the first completely corrected CF (chromatic aberration free) objectives in 1976, and this new technology continues to evolve in the CFI60 (chrome free infinity, 60-mm parfocal shoulder height) objectives, tube lenses, and eyepieces (Nikon). Of the various microscope systems designed with infinite tube length, only this one has combined the other design changes necessary to take full advantage of this concept.
New Lenses
The design of an ideal objective for an infinity microscope system requires more than the usual number of lens elements, since the emergent beam must be focused at infinity. Add to that the demands of fluorescence techniques such as M-FISH (multicolor fluorescence in situ hybridization) (Figure 3), which are based on gathering as many photons as possible, and which require lenses of higher numerical aperture (NA). Add to this the requirements of confocal techniques for high NA, long working distance lenses that penetrate far into thick tissue. To meet these needs, today's lenses must have glass elements of larger physical diameter. Taken together, these requirements make old dimensional standards for lenses obsolete. The example presented in Figure 3 is a multicolor fluorescence image of fibroblasts, captured on film with an Eclipse E800 microscope using the CFI60 60X, NA 1.4 oil immersion objective.




A standard established in the mid-1800s by the Royal Microscopical Society in England set the diameter of the objective mounting threads. This dimension, while generous in its time and appropriate to the old brass microscopes, became a severe restriction on optical design. In addition, former industry standards for parfocal shoulder height - the distance from the specimen to the objective mounting flange - proved inadequate for the complexity of current designs. A new standard for these dimensions (25-mm thread diameter and 60-mm parfocal shoulder height, Nikon) makes innovative new lenses possible and ensures adequate room for improvement. The tube lens has a focal length of 200 mm, allowing lenses of very long working distance combined with high NA. These new standards and the tube lens make possible the free working distances of these objectives.
The CFI60 lenses have higher NAs than are usually available for standard magnifications, providing increased resolution of detail, greater light-gathering power, and high performance in confocal applications. A property shared by many of the objective lenses for the Eclipse instruments is longer-than-usual working distance. This allows thick specimens to be focused from top to bottom without fear of breaking the cover glass or damaging the objective itself. Applying immersion oil is easier, as is changing specimens. Thick-bottomed chambers are usable, and micromanipulation becomes possible with lenses of higher magnification.
In studies that are now revealing the internal mechanisms and dynamic activity of cells, every photon of fluorescent emission is precious. Gathering these with the greatest efficiency demands objectives of the highest possible numerical aperture. The Plan Fluor 40X NA 1.30 oil immersion lens combines magnification, high NA, field flatness, long working distance, and high ultraviolet transmission optimized for efficient work in fluorescence studies. For lenses of equal magnification, image brightness in epi-illumination systems is proportional to the fourth power of the numerical aperture. Calculations show that in comparing an ordinary high-dry lens of 0.65 NA with the 40X immersion lens of 1.30 NA, a 16-fold increase in brightness is obtained.
Better High-Dry Images
Many observations are made with the ordinary, nonimmersion 40X objective, the so-called high-dry lens. At this degree of magnification, an objective needs a fairly high NA to provide the richness of detail that 40X magnification should reveal. The lowest NA usually provided for 40X lenses is 0.65. Even at this NA, the optical performance of the microscope becomes dependent on the one optical component the lens designer and manufacturer cannot control - the coverslip on top of the specimen. Microscope manufacturers recommend a coverslip thickness of 0.17 mm, and they engrave it on the body of the objective (this corresponds to a #1 1/2 coverslip, in the terms of laboratory supply houses).
Many specimens are prepared with coverslips of other thicknesses. This is of little consequence for observations at low powers, but it has a strong influence at 40X and above. In lens designers' terms, the nonstandard coverslips upset the objective's spherical aberration; in users' terms, the image loses contrast and looks cloudy.
While 0.65 is the NA of ordinary 40X lenses, the higher-performance dry objectives can be as high as 0.95. These are so adversely influenced by coverslip thickness that a correction collar must be fitted on the objective. Image quality is optimized by turning it while observing image appearance. Turning the collar alters the internal spacing of some components of the objective, which, unfortunately, also changes the effective focus of the lens. In practice, one must simultaneously turn the collar with one hand and the fine focus knob with the other, while looking for the crispest image. Many users never master this technique. A patented design for high-NA, high-dry lenses (Nikon) has greatly minimized the focus shift, allowing for much easier optimization of image quality. For NAs higher than 0.95, immersion lenses are offered.
Universal Objectives
Every manufacturer lists different special objectives for observation techniques other than ordinary brightfield - techniques such as phase contrast, DIC, and fluorescence. Researchers using multiple techniques once needed to buy several of these objectives for any given magnification. Until now, it was not possible to design a single objective for these four purposes without significant losses in performance. Plan Fluor DLL lenses (Nikon) function in all four of these modes without sacrificing image quality. They provide savings in money, convenience, and space on the nosepiece
Lowest-Power Objective
In life, we usually observe a scene first in overview and then zoom in on the details that catch our eye. At the microscope, we start with low powers first, then move to higher powers. Pathologists, neurologists, and botanists are among the many life science professionals who frequently rely on low power for orientation and literally "getting the big picture." On many microscopes, however, the lowest power using a 10X objective and 10X eyepieces is 100X, quite a leap from natural size. Since microscopists are often reluctant to change to lower-power eyepieces, low-power objectives are the best choice for lower levels of magnification.



With the CFI60 0.5X objective, users can observe and photograph over a wide field of view. With an actual field of view of 50 mm, this objective is useful for macro observations of large specimens such as the tilia stem thin section illustrated in Figure 4. Compared to conventional infinity optical systems, the image area provided by the objective is more than five times greater in size. Actual-size photography is possible on 35-mm film.
Major manufacturers have provided objectives of approx. 4X, 2X, and even 1X power. The CFI Macroplan 0.5X objective, with its special accessories, presents a 5X image at the eyepieces, and will photograph a natural-size, 1X image on 35-mm film (see Figure 4). The lens offers an extremely high level of detail and chromatic correction, allowing the microscope to provide the widest magnification range possible.
Ergonomic Design
A microscope is much more than just optics; it is the laboratory instrument a scientist has the most physical contact with. When buying an instrument at which one may be sitting for hours at a time, it is vital to consider physical comfort. This is something that cannot be easily expressed in a specification sheet. It must be experienced firsthand.
In many older microscopes (and even in some more recent ones), the various controls were placed where they were most convenient for the manufacturer. This sometimes resulted in awkwardness or inconvenience.
All major manufacturers have been incorporating ergonomic considerations in the design of their stands, but the Eclipse instruments bring ergonomic considerations to a higher level. Extensive studies of how users sit at their instruments, measurements of convenient reaching distances, and determinations of comfortable arm and head positions were considered in the designs. Location of the stage handle and focus control knob on the E800 microscope is compared with conventional microscopes in Figure 5(a). By maintaining a natural position and having both hands equidistant from the body, strain is lessened. In addition, the stage handle and fine focus knob are located so they can be manipulated with one hand, enhancing comfortable observation. Erect and tilting eyepiece tubes are available on many of Nikon's microscopes (Figure 5(b)) to ensure that inspection efficiency rises and operator comfort is enhanced by the use of a system in a natural position.



Furthermore, the addition of components to the interlens space has not always been accomplished comfortably. If the components are merely stacked, as most manufacturers do, with the binocular viewing head and the eyepieces on top of them, the result often is an uncomfortably high viewing arrangement, with users craning their necks to peer through the eyepieces. In the Eclipse, up to three components are inserted in the interlens space without the need to change the instrument's constant, convenient eye position.
In the new stands, the most frequently used controls are put in the most convenient places for the microscopist, regardless of the ease of manufacturing. Controls used in conjunction with each other, such as stage movement and fine focus, have been placed where they can be adjusted with the fingers of the same hand. With forearms resting comfortably on the desktop, the most often used controls fall naturally under the fingertips. A much lower position of the stage makes slide changing convenient. Stage controls can be mounted on either side for left- or right-hand operation.
Other properties that are newly designed into the stands include greatly enhanced temporal and thermal stability, which is important for investigations extending over time, such as mitotic studies and embryology. Vibration damping is also increased to improve the resolution of captured images.
Conclusion
Has the ultimate light microscope been created? Though the new instruments on the market have brought the microscope to a high level of development, we will probably never reach that goal as long as scientific research continues. Future needs will require innovations that we cannot yet even foresee. But the best of today's instruments provide the user with vastly more performance and versatility than were possible just a few years ago.
artice source : http://www.microscopyu.com/

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Discussion : some problems on the microscope


Question: What product should I use to lubricate the bearings on the stage of the microscope?
Answer: Each manufacture has their own line of lubricants they recommend.  If you bought everyone for each product it would be extremely expensive.  We use a product called Super Lube made by Permatex.  It should be available from many stores in your area.  We use this product on all brands of microscopes that we service.

Question: My stage seems to slip down out of focus for no reason. What can I do to prevent this?
Answer: There are two main reasons for this problem.  Either the tension control is too loose, or the main bearing system in the stage mechanics needs some adjustments.
You, as the microscope user, can adjust the tension control.  Many microscopes have focus tension controls attached next to the coarse focus control.  This control may be the simple type that you can adjust by just using your hand, or it may take a special tool.  On Olympus or Nikon microscopes the adjustment is usually on the right side of the scope as the stage faces the user.  It is a thin control knob or disc that is placed between the microscope stand and the coarse focus control.  All you have to do is turn this device one way or the other and it will increase or decrease the tension on the coarse focus control knob.  This in turn will keep the stage from slipping down.  Make sure you are not turning the stage lock control, which is normally on the opposite side of the tension controller.  If your microscope takes a special tool to adjust the tension. and you have lost this tool, you will need to contact the microscope manufacture or the company you purchased your microscope from and request the adjustment tool.

If the main bearing system needs adjustment you will should contact a qualified microscope repair technician to do this repair.


Source e: http://www.articlesbase.com/

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Free article : Ho Got Mold Cleaning the Microscope

August 10, 2010

First Aid Got Mold In the Microscope

Microscope maintenance are taxable mushrooms
 
When we observe the object / objects with a microscope, stain / black spots, much like serat2 smooth, opaque, etc .... That's what looks ... ... ... then you are already infected with fungi microscope or lens system may have been damaged.
What should you do?

  • Prepare a 70% alcohol

  • Prepare the lens tissue

  • Prepare a cotton bud

How do it ??
Remove the eyepiece carefully, then clean the surface of the lens up and down with a cotton bud that has been dipped into alcohol beforehand.  After that, rub with lens tissue, and enter back into the microscope tube.
After cleaning and then we check by using a microscope slide preparations.  To view the lens is clean or not to turn the eyepiece the way, if there are specks of something other than the objects involved are still playing meaningful ocular dirty (dirt still stuck to the inside of the lens).
For the objective lens, carefully remove the lens from the revolver, then wipe with a cotton bud tip and the bottom of the last lens with lens tissue.  Then an invisible diterawang lens can be seen "clear clear" or not.  If it still looks blurry means dirt is stuck in the lining of the inner lens. ... It should be dismantled ... .!!!! Please note for the objective lens from at least two layers of the zoom lens according great, the picture click here .
What to do if you like the above? . That is a way to disassemble the lens system using a particular device.  If not skilled or have no experience in dismantling the lenses do not do it alone, it's better penggil experienced technicians to minimize the risk of the lens becomes damaged due to "human error" of trial and error.
The above description is for first aid in particular parts of an optical microscope / lens.
If the tube down his own microscope, macro / micrometer loose, the brace is not good object, etc .... It includes damage to mechanical parts. To better call damage experienced technicians ... because with a microscope usually dabble in it became even more corrupt ... ... ... and to note also tips on choosing a professional technician, among others:
  1. Do not be tempted by offering a cheap service services.
  2. If you take it to a workmanship service at their place (SERVICE NOT TREATED IN PLACE / SCHOOL father / mother) means that Mr / Ms do not know how the settlement of the microscope. Microscope and thus given to the technician as a means of learning how to solve these keruskan microscope. Kalau dipakai belajar, metodenya adalah TRIAL and ERROR . If used to learn, his method is trial and error. If that method get ready condition results 50:50 microscope, can be good or otherwise ... .. could be a deterioration
  3. Find info technician who already has hours of high flying / experience ... ...
  4. Find info capacity and capability of institutions / instansii where they work.
  5. And others ... ...
So hopefully useful ....

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Using Objective Lens 100 times Direct

When studying or observing bacteria, more efficient to start with the oil immersion lens (100 x) and ignore the preliminary steps with objektif lens with low magnification power. This may by students who are current users / familiar and experienced using a microscope that can skip the use of objective lens and 10 x 40 x before using 100 x objective lens directly.

Tools and materials:
  • Preparations of representative microbes: bacteria, fungi, etc..
  • Microscope
  • lens paper
  • Immmersion oil

How it Works:
  1. Place the specimen on the slide in the middle of the skylight, just under the oil immersion lens will be placed.
  2. Add a drop of immersion oil on the specimen
  3. Ensure that there is enough distance between oil and 100 x objective lens before you rotate the lens over the specimen.
  4. Set konensor that its position is just below the specimen slide.  Close the condenser diaphragm almost entirely if you see live specimens, otherwise open the diaphragm condenser when viewing the stained specimen.
  5. By using makrometer, reduce the distance between the lens immersion oil with the specimen, until the lens is submerged in oil and almost touching the specimen. Working distance for the 100 x objective lens is approximately 0.1 mm.
  6. Now see it through a microscope and find the shadow of the specimen by increasing the distance between the specimen and the lens by turning the micrometer.
Move slides forward and back slowly when you are looking for focus. Moving shadow is often more easily seen than the silent shadows. If you do not find the shadow after 3-5 rounds or when the lens is lifted from the oil, repeat steps 5 and 6.

Reasons that are impossible if you do not find anything under the oil immersion lens is as follows:
  1. Too much immersion
  2. Moving too fast micrometer
  3. Condenser is not set correctly (usually a diaphragm iris too open or closed)
  4. Dirty lens
  5. Too few organisms on the slide
  6. Specimens are not attached to the middle of the field before turning the lens
  7. Slide upside down.

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Measurements with a micrometer microscope slide preparations

Posting articles about measurement with a micrometer has been little discussed previously , and on this occasion I tried to explain again as follows.

To calibrate the measuring scale on the microscope there are two scales used, the scale of the ocular (eyepiece placed) and the objective scale (which was placed on the table objects). In principles ocular scale is scale of 1-100, where the distance between the lines the same but unknown value.  While the objective is to scale on a scale of 1-100, where the distance between the lines has a value of 0.01 mm. Ocular scale has not changed in size although the objective magnification changed while the scale is changed in size when the magnification is changed. Therefore, the calibration is done so that the ocular scale has a value of an objective scale parbandingan with ocular scale at every magnification.
Example Calibration:



Both the scale of objective and ocular scale placed coincide with each other, after it was seen where the most coincide lines from left to right. Setelah itu di hitung berapa sekala okuler dan berapa sekala objektifnya dengan rumus SKALA OBJEKTIF/SKALA OKULER. After that the count how many and how much scale scale ocular objective with a formula OBJECTIVE SCALE / SCALE Ocular.

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article : Measurement with the Light Microscope

March 11, 2010


Your microscope may be equipped with a scale (called a reticule) that is built into one eyepiece. The reticule can be used to measure any planar dimension in a microscope field since the ocular can be turned in any direction and the object of interest can be repositioned with the stage manipulators. To measure the length of an object note the number of ocular divisions spanned by the object. Then multiply by the conversion factor for the magnification used. The conversion factor is different at each magnification. Therefore, when using a reticule for the first time, it is necessary to calibrate the scale by focusing on a second micrometer scale (a stage micrometer) placed directly on the stage.

Conversion factor

Identify the ocular micrometer. A typical scale consists of 50 - 100 divisions. You may have to adjust the focus of your eyepiece in order to make the scale as sharp as possible. If you do that, also adjust the other eyepiece to match the focus. Any ocular scale must be calibrated, using a device called a stage micrometer. A stage micrometer is simply a microscope slide with a scale etched on the surface. A typical micrometer scale is 2 mm long and at least part of it should be etched with divisions of 0.01 mm (10 µm).
Suppose that a stage micrometer scale has divisions that are equal to 0.1 mm, which is 100 micrometers (µm). Suppose that the scale is lined up with the ocular scale, and at 100x it is observed that each micrometer division covers the same distance as 10 ocular divisions. Then one ocular division (smallest increment on the scale) = 10 µm at 100 power. The conversion to other magnifications is accomplished by factoring in the difference in magnification. In the example, the calibration would be 25 µm at 40x, 2.5 µm at 400x, and 1 µm at 1000x.
Some stage micrometers are finely divided only at one end. These are particularly useful for determining the diameter of a microscope field. One of the larger divisions is positioned at one edge of the field of view, so that the fine part of the scale ovelaps the opposite side. The field diameter can then be determined to the maximum available precision.

Estimating and reporting dimensions

Be aware that even under the best of circumstances the limit of resolution of your microscope is 1 or 2 µm (or worse) at any dry magnification, and 0.5 µm or so using oil immersion. No directly measured linear dimension or value that is calculated from a linear dimension should be reported with implied accuracy that is better than that. That includes means, surface areas, volumes, and any other derived values. For example, suppose you measure the length of a flagellum on a Chlamydomonas cell at 400x, and determine that it covered 3 1/2 ocular divisions. The length is directly calculated as 3.5 divisions times 2.5 µm per division, which comes out to 8.75 µm. You know, however, that at 400x the absolute best you can do is to estimate to the nearest µm, so before reporting this measurement round it to 9 micrometers (not 9.0, which would imply an accuracy to the nearest 0.1 µm). For more information on reporting uncertain quantities see our Resources section (analytical resources).
The calculation of a volume is subject to error propagation, namely the magnification of an error when deriving a figure from one or more measured variables. For example, suppose you measure the length and diameter of an object to be 65 and 30 micrometers, respectively, assuming a cylindrical shape. The volume is given by the formula v = ¼r2l, where r = radius and l = length. The formula gives a volume of 45, 946 µm3. The volume isn't accurate to the nearest cubic micrometer, however.
Let's make the very optimistic assumption that the measurement of 65 micrometers is indeed accurate to the nearest 1 µm. Then the number 65 means "greater than 64.5 and less than 65.5." The number 30 really means "greater than or equal to 29.5 and less than or equal to 30.5." The smaller set of measurements yields a volume of 44,085 µm3, while the larger yields a volume of 47,855 µm3. False precision would be implied even if one reported a volume of 46,000 µm3, obtained by rounding the middle measurement. It would probably be better to report a range in this case, of 44,000 to 48,000 µm3. By the way, 46,000µm3 is 0.046 mm3, which probably represents a better choice of units in this case.

Making assumptions

In many areas of experimental science, including biosciences, the ability to estimate and make reasonable assumptions is a valuable skill. In order to make some quantitative estimates, particularly of volumes, you will have to make assumptions regarding the shape of some organisms. For example, if a specimen appears round, you would likely make your volume calculation based on the assumption that the specimen is a perfect sphere. For something like aParamecium you might assume a cylindrical shape in order to simplify your estimate, while remaining aware that you could be way off the mark.
A specimen such as Chaos (Pelomyxa) carolinensis represents a real challenge. Ameoboid organisms are irregularly shaped most of the time. Is it flat on the slide, or does it extend up toward the coverslip? Perhaps it is attached to both. What model do you use as a basis for volume estimation? Is it best to assume a particular shape and take measurements at different times? Is it best to estimate a maximum and minimum for each possible dimension and obtain a range of possible volumes? Remember, you are only asked to estimate. Sometimes the best estimates have a potential error of more than an order of magnitude.

source : http://www.ruf.rice.edu/.

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Service Guarantee

March 09, 2010


We give microscope service especially on mechanical repair. Mechanical functions repairing are give to troubled parts (like ocular tube loose, troubles in adjustments knobs, revolver loose, damaged stage, etc).we can reset all into normal condition EXCEPT damaged parts or broken parts for example, worn out adjustments knob gears, we can repair it and have to change with new parts.
We give lenses cleaning service. But if the lens scratched, it can’t be repaired and we have to change with new lens.
Guaranteed?
Repaired microscope can back into normal condition and normal function too. What we have to do after service can see here. We guarantee mechanical parts minimally for at least 6 months. Usually we have to recondition and repair microscope in every 2-3 years after previous service (ideally, we need to repair in every semester).
We not guarantee optical parts… because it depends on behavior of microscope user. It can be lasting longer if we understand and really do optical care or maintenance. If we hadn’t, the optical parts will damage quickly. You can see my previous article about using microscope here

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Microscope slide preparation technique


How to make microscope slide object preparation? Picture above is one of kind sample slide preparation made from complex process. There are many methods for preparation making. Plant tissue preparation is different with histology preparation in making method. On this post, I have concern more to histology and plant tissue preparation making.

Study about preparation making is known as micro technique (in this post, plant micro technique). This study is especially to learning about making long age slide preparation or fresh slide preparation. Paraffin method and wood slicing method are methods that will be learned in this post. In paraffin method, plant organ kept in paraffin and sliced into thin slices and colored before ready to observe in microscope.

Wood slicing method needs special treatment. Specific differences in every kinds of plant need us to knowing well about the life cycle of each plant. We need to know every reagent give effect to each kind of plants.

Making of plant slide preparation

Making of animal slide preparation

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Making of plant slide preparation

March 08, 2010


Sampling
This step is to decide what kind of plant and organ or tissue that we need. Click here to see the process
Fixation
Fixation is using FAA solution (formalin, alcohol, acetic acid glacialic) for at least 24 hours. Fixation purpose is to makes sample died and increase durability of sample without change the condition and appearance of the sample. But if we not do this process carefully, it can make sample damaged. To see fixation process, click here or here.
Aspration
After fixation, we have to out air in plant tissue to avoid penetration of FAA solution blocked. We can use this tools and the process is like this.
Dehydration
This step purposes is to out water in plant tissue so that tissue can exposed with paraffin. We usually do this process with alcohol-xylene solution or alcohol TBA solution. See each step of dehydration here.
Clearing
Clearing purposes is to make sample colorless. See clearing step here.
Infiltration
Infiltration is process to make paraffin can expose on the plant tissue. Infiltration process here.
Embedding
On this step, we need container to make paraffin box or cubicle. Cubicle paraffin is used as place of plant tissue. Embedding process showed here
Paraffin slicing
See the process here.
Patching
We need totally clean of object glass to avoid loosing the slide. wipe up the object glass with dry and clen wiper. For patching agent, we can use Haupt’s solution. see the process here.
coloring
To simplify this step, we can make coloring schedule. The simplest coloring method is progressive method when intensity of color in tissue is straight equivalent with time to submerged in coloring agent. For chart sample, here
Covering with glass cover

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