technical information:
Microscope:
Until 2006-12-04 I have been using a Novex KB microscop with 3 different eye-pieces
(WF10, WF16 und WF20, 23,1 mm diameter)
and 4 achromatic objectives (4x/0.10, 10x/0.25, 40x/0.65 and S100x/1.25 oil).
Since 2006-12-05 I am using a Zeiss Axiolab drb KT with Bino-tube and the following objectives:
2,5x/0,06 A-Plan
5x/0,12 CP-Achromat
10x/0,3 Ph1, Plan-Neofluar
20x/0,5 Ph2, Plan-Neofluar
40x/0,75 Ph2, Plan-Neofluar
63x/0,8 Achroplan
100x/1,3 Plan-Neofluar, Oil
In January 2003 I additionaly baught a stereomicroscop Novex RZB-SF with 2 different eye-pieces
(WF10 und WF20). The zoomobjective has a magnification-range from 0,65x to 4,5x.
Cameras:
The fotos and videos dated up to 2005-04-30 have been shot with a
Philips ToUCam Pro 740 (640x480 pixel). For this the webcam was fixed with a
stand over the eye-piece.
The fotos and videos since 2005-05-01 are shot with a Canon Powershot A85 (4 Megapixels).
For this I am using an adapter that fixes the camera to the ocular-tube.
Sine December 2008 I am using a Canon Powershot G9 together with the Zeiss Universal-Adapter.
scale, objectmicrometer:
Most pictures are provided with a scale in µm. The objectmicrometer consists of
a slide on which a foil is fixed. On this foil is printed a 1 mm long and in 100 parts (1 part == 10 µm)
divided scale. First this scale is shooted under the microscope with all possoble combinations of
eye-piece and objectiv. Afterwards for each magnification a metering-bar is drawn into the picture and is
saved in a seperate layer. Same resolution provided, the metering-bar now can be copied into
a new picture. The use use of expensive scaled eye-pieces is obsolete now.
picture of the objectmicrometer with metering-bar
JUNG Studentsmicrotom AB:
The thin sections since >April 2010 are done with a JUNG Studentsmicrotom AB.
Before I did many section by hand or with he aid of a hand-cyclinder-microtom.
A description of embedding biological objects in polyethylenglycol (PEG)can be found here
: Embedding in PEG
JUNG Studentsmicrotom AB
Thin Cross Sections of Lichens and Mosses without using a microtom
With a little practice it is possible to obtain cross sections of satisfactory thickness by manual cutting.
There is no need to buy an expensive microtom. Only a razor blade (cut in half), a stereomicroscope
and PEG 1500 (polyethylenglycol) as embedding medium is needed.
Begin with the dry material. Prior to cutting the dry material is placed into a 20 % aqueous solution of PEG 1500 for 24 h.
Then the wet, with PEG-solution saturated, leaf or a part from it is laid on a slide. Allow to dry for 24 h. After that
the material is impregnated with PEG and at the same time it is pasted a bit onto the slide.
Now we can start the cutting under the stereomicroscope. The left forefinger is laid on the material and
once a relative broad piece is cut off along the fingertip. In this way a straight cutting edge
is obtained and from this you begin. The left forefinger is now withdrawn a little bit or you just push
the razor blade a bit tighter to your fingertip. Then cut off the thin section by moving the razor blade along your
fingertip. A little practice is still needed and with the time you will develop a certain sensitiveness.
The sections are transferred into a 10 % solution of PEG 1500. This is to avoid a too quick dissolving of
the PEG that could damage the section. Cross sections of lichens can be enclosed in Euparal without any staining.
When dealing with mosses you might want stain the section and in this case the section investigated directly in water.
Literature concerning the embedding in PEG can be found here:
Halle W (1959): Die Verwendung von wasserlöslichen Polywachsen als Einbettungsmittel in der histochemischen und histologischen Technik. Mikrokosmos Band 48, Seite 275
Türler S (1972): Ein ideales Einbettungsmittel? Erfolge und Schwierigkeiten mit Polyäthylenglykol. Mikrokosmos Band 61, Seite 91
Theiler R (1973): Polyäthylenglykol als Hilfsmittel beim Gefrierschneiden. Mikrokosmos Band 62, Seite 59
Krauter D (1979): Das Kosmos-Mikrotom. 3. Wahl der Objekte. Durchtränkung mit Paraffin oder Polyäthylenglykol. Mikrokosmos Band 68, Seite 144
Jentzen A (1988): Erfahrungen mit Histowachs. Mikrokosmos Band 77, Seite 57
Pareto A (1989): Rasches Einbettungsverfahren für krautige Pflanzenteile in Polyäthylenglykol. Mikrokosmos Band 78, Seite 255
Pareto A (1989): Polyethylenglykol als besonders gut geeignetes Einbettungsmedium für trockene Samenschalen von Leguminosen. Mikrokosmos Band 78, Seit 337
Gruber M (1989): Einbettung von Pflanzenteilen in Polyethylenglykol. Herstellung von perfekten Dünnschnitten mit dem Handmikrotom. Mikrokosmos Band 78, Seite 124
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