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Description of this part for the microscope.

objective nosepiece and the microscope arm. In the Carl Zeiss Jena Jenalumar microscope, a fluorescence filter cube slides into position above the objective revolver. Inside this holder there is a longitudinal dovetail guide along which the fluorescence filter cubes slide. It also contains a spring steel detent that provides a distinct "click" to indicate the filter position as the fluorescence filter cube is moved along the dovetail guide.

The objective revolver is attached to this holder with screws, and the complete assembly consisting of the holder and objective turret is then screwed to the microscope arm.

The complete objective nosepiece module for Carl Zeiss Jena Jenalumar or Jenaval microscopes consists of:
- the objective revolver (also called the objective nosepiece, nosepiece disc or objective turret)
- the intermediate mounting bracket (nosepiece holder).

In both microscope models, the Carl Zeiss Jena Jenalumar and the Carl Zeiss Jena Jenaval, the first component—the objective revolver—is identical and interchangeable between the two models. Only the intermediate mounting bracket differs, as it attaches the revolver to the microscope arm. In other words, the nosepiece holder used in the Carl Zeiss Jena Jenalumar microscope is different from the one used in the Carl Zeiss Jena Jenaval microscope, but both holders have exactly the same objective revolvers attached to them.

This listing includes only the intermediate holder for the Carl Zeiss Jena Jenalumar model, without the objective nosepiece.

Interestingly, this component is made of aluminium, whereas the corresponding component performing the same function in the Carl Zeiss Jena Jenaval microscope is manufactured from a ZnAl alloy. Cast or injection-moulded ZnAl components made by Carl Zeiss Jena carry identification numbers that allow them to be identified. In the Jenaval microscope this number is 2643 (full marking: Si10 CZ 2643). The objective nosepiece holder used in the Jenalumar does not carry such a number.

Another useful piece of information is that the sliding fluorescence filter cube from the Carl Zeiss Jena Jenamed Fluorescence microscope fits the dovetail guide incorporated into this nosepiece holder.

The gallery includes photographs of the complete assembly consisting of the objective nosepiece and its holder for the Jenalumar microscope, making it clear how these two components are connected.

This database also contains, under item number 99678, the separate objective revolver without the holder.

Description of this part for the microscope.

The complete set presented here consists of three components:
1. a small metal plate marked with the numbers 1 to 8 – these identify the terminal positions
2. an electrical tab terminal strip with eight terminals, housed in a plastic body
3. the rear sheet-metal cover of the microscope arm with the printed 6V illumination wiring diagram

This set was removed from a Carl Zeiss Jena Jenalumar microscope.

Components "1" and "2" (the numbered plate and the electrical tab terminal strip) are universal and fit the following microscope models:
- Carl Zeiss Jena Jenalumar
- Carl Zeiss Jena Jenaval
- Carl Zeiss Jena Jenavert
- Carl Zeiss Jena Jenapol

Component "3" (the rear sheet-metal cover of the microscope arm)
- fits the Carl Zeiss Jena Jenalumar microscope
- does not fit the Carl Zeiss Jena Jenaval microscope
- I do not know whether it fits the Carl Zeiss Jena Jenavert or Jenapol microscopes, as I have not personally tested this.

The 6V supply wires coming from the power supply are connected to the input terminals on the underside of this electrical tab terminal strip. The power supply is built into the microscope base. The lampenhaus fitted with a 6V 25W halogen bulb is connected to the output terminals on the upper side. In the Carl Zeiss Jena Jenaval and Jenalumar microscopes this supplies the transmitted-light illuminator. In the Carl Zeiss Jena Jenavert microscope it supplies the reflected-light illuminator.

In microscope versions equipped with two illuminators, only one of them can be powered from the power supply built into the microscope base, because the built-in power supply has a maximum output power of 25 W. The second illuminator requires an external power supply appropriate for the particular light source (a halogen lamp, a fluorescence light source, or—in the case of LED illuminators—an LED power supply with a dimmer).

This database also contains, under item number 99694, the same component together with the rear sheet-metal cover of the microscope arm from a Carl Zeiss Jena Jenaval microscope. You can compare the two versions to see the difference in the size of the rear sheet-metal cover between the Carl Zeiss Jena Jenaval and Jenalumar models.

If you need only one component from this set—either the rear microscope arm cover or only the electrical tab terminal strip—please contact us by email or through social media.

Description of this part for the microscope.

objective nosepiece and the microscope arm of the Carl Zeiss Jena Jenaval microscope.

The complete assembly (objective revolver ↔ holder ↔ microscope arm) is connected together with screws.

The complete objective nosepiece module for Carl Zeiss Jena Jenalumar or Jenaval microscopes consists of:
- the objective revolver (also called the objective nosepiece, nosepiece disc or objective turret)
- the intermediate mounting bracket (nosepiece holder).

In both microscope models, the Carl Zeiss Jena Jenalumar and the Carl Zeiss Jena Jenaval, the first component—the objective revolver—is identical and interchangeable between the two models. Only the intermediate mounting bracket differs, as it attaches the revolver to the microscope arm. In other words, the nosepiece holder used in the Carl Zeiss Jena Jenaval microscope is different from the one used in the Carl Zeiss Jena Jenalumar microscope, but both holders have exactly the same objective revolvers attached to them.

This listing includes only the intermediate holder for the Carl Zeiss Jena Jenaval model, without the objective nosepiece.

Cast or injection-moulded ZnAl components manufactured by Carl Zeiss Jena carry identification numbers that allow them to be identified. This component bears the number 2643 (full marking: Si10 CZ 2643).

This database also contains:
- under item number 99678 the separate objective revolver without the holder
- under item number 99682 the separate objective nosepiece holder for the Carl Zeiss Jena Jenalumar microscope
- under item number 99388 the complete objective nosepiece with holder for the Carl Zeiss Jena Jenaval model

Description of this part for the microscope.

It is not an illuminator holder in the literal sense. The illuminator is secured with screws to the sides of the microscope's vertical arm. Instead, the central circular opening in this component is designed to receive and accurately position the cylindrical light-output section of the illuminator (lamphouse).

Microscopes designed for reflected-light operation (either exclusively or in addition to transmitted light), such as the Carl Zeiss Jena Jenalumar, Jenavert and Jenapol-U, have a different upper horizontal microscope arm from models intended exclusively for transmitted light, such as the Carl Zeiss Jena Jenaval. The reflected-light arm includes a slot for filter sliders, a slot for an aperture slider and, of course, an angled mirror.

Interestingly, this component is also present in Carl Zeiss Jena Jenaval microscopes, even though the standard version of this model is not equipped with an EPI reflected-light illuminator. Since it is not used there, it is normally covered by the rear sheet-metal cover of the microscope arm. This is exactly why the rear cover of the Carl Zeiss Jena Jenalumar microscope is shorter than that of the Jenaval model—it does not have to cover this component (see item no. 99679 in this database).

This component fits the following microscope models:
- Carl Zeiss Jena Jenalumar
- Carl Zeiss Jena Jenaval
- Carl Zeiss Jena Jenavert
- Carl Zeiss Jena Jenapol

- in the Carl Zeiss Jena Jenaval microscope this component is hidden behind the rear sheet-metal cover and is not used
- in the Carl Zeiss Jena Jenalumar 50 this component receives the small 50W HBO fluorescence illuminator
- in the Carl Zeiss Jena Jenalumar 250 with the large integrated lamphouse, this component receives the light-output section of the 250W HBO fluorescence illuminator
- in the Carl Zeiss Jena Jenavert this component receives the 50W/100W halogen illuminator
- Carl Zeiss Jena Jenapol microscopes may be equipped with various EPI reflected-light illuminators

Cast or injection-moulded ZnAl components manufactured by Carl Zeiss Jena carry identification numbers that allow them to be identified. This component bears the number 2650 (full marking: Si10 2650).

Description of this part for the microscope.

Carl Zeiss Jena Jenaval
- Carl Zeiss Jena Jenalumar
- Carl Zeiss Jena Jenapol
- Carl Zeiss Jena Jenavert

The function of this microscope component is to reflect the light coming from the microscope base vertically upwards so that, after passing through the microscope slide with the specimen and the objective, it reaches the eyepieces and finally the user's eyes.

This component is a metal casting with a circular opening. The mirror is mounted in this opening. The complete assembly is fastened to the microscope base with screws.

Metal cast or injection-moulded microscope components manufactured by Carl Zeiss Jena carry identification numbers. The part to which the mirror is attached bears the number 2649 (full marking: Si10 CZ 2649).

Replacement of the right-angle mirror in Carl Zeiss Jena microscopes may be necessary in the following situations:
- if the mirror has become significantly scratched due to improper cleaning (minor scratches are usually not visible during normal use)
- if the reflective silver coating of the installed mirror has become oxidised
- if the mirror has been damaged, chipped or cracked, for example after becoming detached from its mount
- if the metal casting holding the mirror chips or breaks due to age, stresses caused by the mounting screw or mechanical damage

Description of this part for the microscope.

The complete set presented here consists of three components:
1. a small metal plate marked with the numbers 1 to 8 – these identify the terminal positions
2. an electrical tab terminal strip with eight terminals, housed in a plastic body
3. the rear sheet-metal cover of the microscope arm with the printed 6V illumination wiring diagram

This set was removed from a Carl Zeiss Jena Jenaval microscope.

Components "1" and "2" (the numbered plate and the electrical tab terminal strip) are universal and fit the following microscope models:
- Carl Zeiss Jena Jenalumar
- Carl Zeiss Jena Jenaval
- Carl Zeiss Jena Jenavert
- Carl Zeiss Jena Jenapol

Component "3" (the rear sheet-metal cover of the microscope arm)
- fits the Carl Zeiss Jena Jenaval microscope
- does not fit the Carl Zeiss Jena Jenalumar microscope
- I do not know whether it fits the Carl Zeiss Jena Jenavert or Jenapol microscopes, as I have not personally tested this.

The 6V supply wires coming from the power supply are connected to the input terminals on the underside of this electrical tab terminal strip. The power supply is built into the microscope base. The lampenhaus fitted with a 6V 25W halogen bulb is connected to the output terminals on the upper side. In the Carl Zeiss Jena Jenaval and Jenalumar microscopes this supplies the transmitted-light illuminator.

In microscope versions equipped with two illuminators, only one of them can be powered from the power supply built into the microscope base, because the built-in power supply has a maximum output power of 25 W. The second illuminator requires an external power supply appropriate for the particular light source (a halogen lamp, a fluorescence light source, or—in the case of LED illuminators—an LED power supply with a dimmer).

This database also contains, under item number 99679, the same component together with the rear sheet-metal cover of the microscope arm from a Carl Zeiss Jena Jenalumar microscope. You can compare the two versions to see the difference in the size of the rear sheet-metal cover between the Carl Zeiss Jena Jenaval and Jenalumar models.

If you need only one component from this set—either the rear microscope arm cover or only the electrical tab terminal strip—please contact us by email or through social media.

Description of this part for the microscope.

Jenapol
- Carl Zeiss Jena Jenalumar

This cover serves two main functions in the microscope:
- it protects the power supply and all electrical components built into the microscope base, protecting both the electrical system and the user from electric shock
- it protects the optical components located inside the microscope base from dust and other contamination

The base of Carl Zeiss Jena Jenaval, Jenalumar and similar microscopes contains part of the optical light path, and this area occasionally requires maintenance, especially cleaning. Since these microscopes are now more than 30 years old, it is not uncommon to find examples with this cover missing because it has been lost over the years.

Description of this part for the microscope.

Jena microscope models:
- Carl Zeiss Jena Jenaval
- Carl Zeiss Jena Jenalumar
- Carl Zeiss Jena Jenapol
- can also be installed in a Carl Zeiss Jena Jenavert microscope to add transmitted-light capability

This component is located inside the microscope base. It receives the light beam from the illuminator, homogenises it (by diffusing the image of the lamp filament using a frosted filter acting as a diffuser) and then properly collimates it using a collimating lens. The prepared light beam then passes through another lens before reaching the right-angle mirror (sold as a separate component).

This part is well known on the secondary market among hobbyists and engineers building their own DIY optical projects, where it is frequently reused.

Interestingly, microscope versions intended exclusively for reflected-light operation (for example, the basic versions of the Carl Zeiss Jena Jenavert) do not contain this component because they do not have a transmitted-light optical path. However, both the microscope arm and the microscope base are identical to those used in transmitted-light models. This makes it possible to upgrade such an EPI microscope for transmitted-light operation by installing the complete lower transmitted-light optical path. The component offered here is one of the parts required for this conversion.

In the last photograph, an arrow indicates where this component is located inside the microscope, making it easy to identify.

Description of this part for the microscope.

Jena microscope models:
- Carl Zeiss Jena Jenaval
- Carl Zeiss Jena Jenalumar
- Carl Zeiss Jena Jenapol
- Carl Zeiss Jena Jenavert

This component serves almost exclusively a cosmetic purpose. At both the top and bottom of the sheet-metal cover there are openings through which the long screws pass. These screws secure the transmitted-light lamp housing to the rear of the microscope body (at the bottom) or the reflected-light EPI lamp housing (at the top).

Each microscope has two of these sheet-metal covers—one on the left side and one on the right. Both are identical, so there is no difference between the left-hand and right-hand cover.

The cover is attached using ordinary adhesive and, after many years, it may simply come loose and fall off. These covers are also sometimes lost during repairs or maintenance, so older microscopes are often missing them. Reattaching an original cover is an easy way to restore the microscope to its original appearance.

In the last photograph, an arrow indicates where this component is located on the microscope, making it easy to identify.

Description of this part for the microscope.

models:
1. Carl Zeiss Jena Jenaval
2. Carl Zeiss Jena Jenalumar
3. Carl Zeiss Jena Jenapol
4. Carl Zeiss Jena Jenavert

1. In Carl Zeiss Jena Jenaval microscopes, this lamp house is used as the transmitted-light illuminator.

2a. In Carl Zeiss Jena Jenalumar 50 microscopes (equipped with the small HBO 50 fluorescent lamp house, identical to the one used in Carl Zeiss Jena Jenamed Fluorescence microscopes), this lamp house serves as the transmitted-light source.

2b. Carl Zeiss Jena Jenalumar 250 microscopes are equipped with a large integrated lamp house. The unit offered here is therefore not compatible with this model.

3. In Carl Zeiss Jena Jenapol microscopes, this halogen lamp house is used both for transmitted light (mounted underneath) and for reflected light (mounted on the top). However, some Jenapol versions are equipped only for transmitted-light operation or only for reflected-light operation.

4. Carl Zeiss Jena Jenavert microscopes are normally equipped with a different lamp housing for reflected light. However, when the original unit is missing, users often modify a lamp house like the one offered here for DIY projects. In addition, if a Jenavert is equipped with a transmitted-light optical path, this lamp house is used as its transmitted-light source.

The lamp house is attached to the microscope using two long screws. Unusually—and this often makes them difficult to find—the screws are removed FROM THE FRONT of the microscope. Their heads are accessible through openings in the white sheet-metal side covers of the microscope body. These covers with the screw openings are shown in this database under item number 99692.

This lamp house contains a filter wheel with four positions for 32 mm diameter round filters. It is fitted with the same filter configuration originally supplied by Carl Zeiss Jena for the Jenaval model:
- one position is empty
- Carl Zeiss Jena C312 blue filter
- Carl Zeiss Jena D282 grey filter
- Carl Zeiss Jena V231 green filter

The filter wheel is an optional part of this lamp house. The example offered here is fitted with it, but it can be removed and the illuminator will still function perfectly as a light source.

Cast or injection-moulded ZnAl components manufactured by Carl Zeiss Jena carry identification numbers. The housing of this lamp house bears the number 2670 (full marking: 2670 Si10 CZ).

In the last photograph, an arrow indicates where this component is located in the microscope, making it easy to identify.

Description of this part for the microscope.

transformer assembly installed inside the microscope base. It converts an input voltage of 110–240 V into a 6 V output with a maximum power of 25 W. It is intended to power a halogen lamp house. An example of this lamp house can be found in this database under item number 99693.

This is not the power supply for the 50W/100W reflected-light lamp housing used on the Carl Zeiss Jena Jenavert. It is also not the power supply for the fluorescent lamp houses used on the Carl Zeiss Jena Jenalumar.

Compatible with the following microscope models:
- Carl Zeiss Jena Jenaval
- Carl Zeiss Jena Jenalumar
- Carl Zeiss Jena Jenapol
- Carl Zeiss Jena Jenavert

If you only need one component from this assembly—for example the transformer, one of the electronic circuit boards or just the potentiometer used to adjust the lamp brightness—please contact us by email or through our social media channels.

This complete assembly may be useful for solving the following microscope problems, among others:
- if the microscope illumination no longer works because of a faulty power supply. This may be caused by mains voltage surges, ageing electronic components or damage resulting from incorrect modifications (for example, conversion to LED lighting)
- if the illumination works but the brightness can no longer be adjusted because the potentiometer is worn out or defective

Originally, the complete power supply assembly (transformer, electronic circuit boards and wiring) is installed inside the microscope base, and it is offered here exactly in that configuration. How can it be used?
- the electrical components can be removed and used as spare parts to repair a damaged power supply
- the complete microscope base can be transplanted to another microscope (please note that it does not include any optical components)

An interesting DIY modification is to leave the power supply in the base offered here and then place the microscope on top of that base. This effectively raises the microscope while also providing an integrated power supply for a second lamp house.

Description of this part for the microscope.

microscope models:
- Carl Zeiss Jena Jenaval
- Carl Zeiss Jena Jenalumar
- Carl Zeiss Jena Jenapol
- can also be installed in a Carl Zeiss Jena Jenavert microscope to add transmitted-light capability

This component is located inside the microscope base and enables the microscope illumination to be adjusted according to the Köhler illumination principle.

Interestingly, microscope versions intended exclusively for reflected-light operation (for example, the basic versions of the Carl Zeiss Jena Jenavert) do not include this transmitted-light field diaphragm because they do not have a transmitted-light optical path. However, the microscope base is identical to that used in transmitted-light models. This makes it possible to upgrade such an EPI microscope for transmitted-light operation by installing the complete lower transmitted-light optical path. The field diaphragm offered here is one of the components required for this conversion.

In the last photograph, an arrow indicates where the transmitted-light field diaphragm is located inside the microscope base, making this component easy to identify.

Description of this part for the microscope.

unscrewed. It is mounted onto the dovetail guide located underneath the microscope stage carrier and secured with a clamping screw.

Carl Zeiss Jena Ergaval microscopes were originally equipped with a condenser attached to the "MO" holder. This holder has a permanently mounted iris diaphragm and wide-field lens, while the condenser itself is screwed into the upper thread. In this configuration, the condenser cannot be exchanged.
The Carl Zeiss Jena Fluoval uses a similar arrangement, whereas the Carl Zeiss Jena Amplival was originally equipped with a panchromatic condenser.

If the user wishes to use other condensers (including those made by manufacturers other than Carl Zeiss Jena), the original condenser holder must be replaced with the MZ condenser holder. Once this has been done, any microscope condenser with a mounting diameter of 39.5 mm can be installed. Condensers with a 37 mm mounting diameter can also be used if they are fitted with a suitable adapter ring.

This is exactly such a holder for interchangeable condensers.

Basic specifications:
Manufacturer: Carl Zeiss Jena
Original documentation name and model: Kondensor-Einhänger MZ
Colour: grey, the version manufactured for the Mikroval microscope series
Internal diameter: for mounting condensers with a 39.5 mm mounting diameter (for example the Carl Zeiss Jena cardioid darkfield condenser)
Condenser retaining screw: yes, central condenser clamping screw
Centering screws: yes, two condenser centering screws
Microscope mounting: dovetail

Although this component is grey, it is also compatible with older black Carl Zeiss Jena microscopes from the 1950s and 1960s (it simply will not look completely original unless it is repainted).

This condenser holder is compatible with, among others:
- Carl Zeiss Jena Ng (black microscope)
- Carl Zeiss Jena Polmi-A (black microscope)
- Carl Zeiss Jena Nf (black microscope)
- Carl Zeiss Jena Nu (the NU-2 version is grey)
- Carl Zeiss Jena Ergaval (grey microscope)
- Carl Zeiss Jena Fluoval / Fluoval-2 (grey microscope)
- Carl Zeiss Jena Amplival and its variants (grey microscope)
- Carl Zeiss Jena Docuval (grey microscope)

Various names are used for this microscope component, including:
- condenser holder
- condenser carrier
- condenser mount
- condenser support

The last photograph includes an excerpt from the original manufacturer's documentation. An arrow indicates this exact model of condenser holder, making it easy to identify the component.

Description of this part for the microscope.

unscrewed. It is mounted onto a dovetail guide located underneath the microscope stage carrier. The condenser holder is secured to the guide with a clamping screw.

It can accommodate any microscope condenser with a mounting diameter of 39.5 mm, regardless of the manufacturer. Condensers with a 37 mm mounting diameter can also be used if they are fitted with a suitable adapter ring.

Basic specifications:
Manufacturer: Carl Zeiss Jena
Original documentation name and model: Kondensor-Einhänger MZ
Colour: black, the version manufactured for the black Carl Zeiss Jena microscopes from the 1950s and 1960s
Internal diameter: for mounting condensers with a 39.5 mm mounting diameter (for example the Carl Zeiss Jena cardioid darkfield condenser)
Condenser retaining screw: yes, central condenser clamping screw
Centering screws: yes, two condenser centering screws
Microscope mounting: dovetail

Although this microscope component is black, it is also compatible with the newer grey Carl Zeiss Jena microscopes of the Mikroval series.

This condenser holder is compatible with, among others:
- Carl Zeiss Jena Ng (black microscope)
- Carl Zeiss Jena Polmi-A (black microscope)
- Carl Zeiss Jena Nf (black microscope)
- Carl Zeiss Jena Nu (the NU-2 version is grey)
- Carl Zeiss Jena Ergaval (grey microscope)
- Carl Zeiss Jena Fluoval / Fluoval-2 (grey microscope)
- Carl Zeiss Jena Amplival and its variants (grey microscope)
- Carl Zeiss Jena Docuval (grey microscope)

Various names are used for this microscope component, including:
- condenser holder
- condenser carrier
- condenser mount
- condenser support

The last photograph includes an excerpt from the original manufacturer's documentation. An arrow indicates this exact model of the condenser holder, making it easy to identify the component.

Description of this part for the microscope.

reflector, performs two functions:
- it contains a barrier filter (emission filter) for the 450 nm wavelength
- it acts as an angular mirror, reflecting the light beam from the EPI fluorescence illuminator vertically downward through the objective toward the specimen.

This fluorescence filter cube fits the following EPI fluorescence microscopes:
- Carl Zeiss Jena Fluoval Fluoreszenz
- Carl Zeiss Jena Fluoval-2 (built on the Carl Zeiss Jena Amplival microscope platform)

Important – this microscope component does not fit the first version of the Carl Zeiss Jena Fluoval microscope. The Fluoval microscope (without "2") does not use a filter cube. Instead, it has a simple permanently mounted swing-out barrier filter.

The filter cube has two positions:
- empty, for normal transmitted-light operation
- 450 nm for reflected-light fluorescence (EPI) operation

Mechanically, this filter cube is installed between the objective nosepiece and the microscope head. It slides into a dedicated slot and moves along a dovetail guide. On the Carl Zeiss Jena Laboval Fluoreszenz microscope, this slot is located in the additional upper horizontal arm of the EPI fluorescence illuminator. On the Carl Zeiss Jena Fluoval-2 microscope, the slot is located in the EPI fluorescence arm, which is an integral part of the microscope. The Fluoval-2 is based on the Carl Zeiss Jena Amplival microscope, which has a modular design. Mechanically, the Fluoval-2 is essentially an Amplival equipped with an upper EPI fluorescence arm.

Sliding the cube along this dovetail guide switches between the empty position (transmitted light) and EPI fluorescence with the 450 nm filter.

Description of this part for the microscope.

diameter: 23.2 mm

This eyepiece allows the microscope image to be projected onto a surface such as a wall, ceiling or projection screen.

Originally, this eyepiece model was supplied with the Carl Zeiss Jena Pictoval projection microscope. It can also be installed on virtually any microscope from any manufacturer with a 23.2 mm eyepiece tube.

Important: Projecting a microscope image requires a very large amount of light, so a high-power illuminator is necessary.

Description of this part for the microscope.

This filter is mounted in the sheet-metal housing of the large HBO 250W fluorescence illuminator. This illuminator is part of a large mirror light beam splitter used in Carl Zeiss Jena Jenalumar microscopes. The KG filter is designed to absorb heat (infrared radiation) emitted by the high-pressure HBO mercury lamp.

Please note that there is also a version of the Carl Zeiss Jena Jenalumar microscopes with a small 50W HBO illuminator. This KG filter glass was removed from a large 250W illuminator.

On the used market, in microscopy forums and in microscopy groups, several names are used for this filter, all referring to the same type of filter:
- KG filter / KG glass
- heat filter
- heat absorbing filter
- heat absorption filter
- heat-absorbing glass
- heat absorption glass
- absorption filter
- IR filter
- infrared blocking filter
- infrared cut filter
- KG3 heat absorption filter

This microscope element is highly susceptible to damage. When this happens, the filter needs to be replaced, for example with the filter presented here. Here are examples of damage that can occur during use of the fluorescence illuminator and reasons why replacement of the filter may be necessary:
- the KG filter may crack or become cloudy due to overheating
- the filter may also chip or break as a result of mechanical damage, for example during transport
- the filter may sometimes be damaged during improper maintenance

High-performance heat filters such as this KG filter used with a 250W lamp are very often used by people building their own DIY projects. The housing with screw mounting makes this particularly convenient.

The last photo in the gallery shows the housing of the HBO 250W illuminator (lampenhaus), with an arrow indicating which element is being described and where it is located inside the illuminator. This makes it possible to identify the element unambiguously.

Description of this part for the microscope.

susceptible to damage, and good and efficient passive cooling is very important in an HBO 250W illuminator.

In Carl Zeiss Jena Jenalumar microscopes, the large HBO 250W fluorescence illuminator is attached to the Spiegelhaus for light beam splitting. It has two such heat sinks – one at the bottom and one at the top of the lamp housing.

For certainty, the photo gallery shows the exact dimensions of this element. The last photo shows the complete illuminator from which this element was removed, allowing the compatibility to be confirmed with certainty.

Description of this part for the microscope.

fluorescence illuminator behind the high-pressure mercury burner. In Carl Zeiss Jena Jenalumar microscopes, the large HBO 250W fluorescence illuminator is attached to the Spiegelhaus for light beam splitting.

The function of this element is to collect and reflect toward the KG filter the light that "shines and escapes to the rear".

This mirror, located directly next to the light source, is susceptible to damage, among other things due to exposure to high temperatures. Additionally, when the high-pressure mercury burner explodes (which occasionally happens), the mirror is very often damaged by the explosion.

The photo gallery shows the exact dimensions of this element. The last photo shows the HBO 250W illuminator for a Carl Zeiss Jena Jenalumar microscope, allowing the compatibility to be confirmed with certainty.

Description of this part for the microscope.

head in Carl Zeiss Jena Pictoval projection microscopes (microprojectors). The adjustable tilt angle of the eyepiece tube, which held a projection eyepiece (usually f=100), allowed the position of the projected image on the projection surface to be changed.

Basic parameters:
Manufacturer: Carl Zeiss Jena
Eyepiece mounting diameter: 23.2 mm
Mounting to the microscope arm: 41 mm diameter dovetail ring

Because this microscope head has a Carl Zeiss Jena standard microscope mount (a 41 mm diameter dovetail ring), it can be mounted on most microscopes from this manufacturer (e.g. Carl Zeiss Jena Eduval, Laboval, Ergaval, Amplival, etc.), as well as on microscopes made by Lomo (e.g. Lomo Biolam), IOR and Meopta.

It seems useful to mention a few points:
- never look through this microscope head with the naked eye if a projection eyepiece is installed in it and the head is mounted in a Carl Zeiss Jena Pictoval microprojector. This may result in loss of eyesight due to the very high light output emitted by this microscope
- when mounting this microscope head on a microscope other than a Carl Zeiss Jena Pictoval, a different magnification scale may be obtained than with the original heads designed for the particular microscope model
- projecting a microscope image requires a great deal of light, i.e. a powerful illuminator. This is worth remembering if you intend to use this head to project an image from biological microscopes with standard incandescent illumination (e.g. 15 W 6 V), which is definitely not sufficient
- visual observation using this microscope head may be inconvenient because it has a different (smaller) tilt angle than standard monocular or binocular microscope heads

Description of this part for the microscope.

here is not a standalone lamp housing (such as part number 99693 in this database). It is an internal component of the large, integrated illuminator used in Carl Zeiss Jena Jenalumar 250 microscopes.

Carl Zeiss Jena Jenalumar microscopes are available in two main versions:
1. with two small illuminators – with a separate 6 V 25 W halogen illuminator in a small housing (for transmitted light) and a separate HBO 50 W fluorescence illuminator in a small housing (for reflected light)
2. with a large, integrated module consisting of a mirror light splitter, an integrated transmitted-light module with a 6 V 25 W halogen lamp, and a large lamp housing for HBO 250 W fluorescence illumination

The component offered here is part of the second version of the Jenalumar microscope.

Basic parameters of this illuminator module:
Supported lamp: Narva HLWS 6 V 25 W halogen lamp
6 V power connection: this illuminator is connected to the distributor rail (see part number 99679 in this database)
Cooling: passive, in two ways. The Narva HLWS lamp has integrated cooling in the form of “wings”, while the entire illuminator is covered with a cover incorporating a finned heat sink (this is a separate component and is not part of the illuminator offered here)

The photo gallery shows the exact dimensions of this component. The last photo shows the complete HBO 250 W illuminator for the Carl Zeiss Jena Jenalumar microscope, with an arrow indicating this halogen illuminator module. This makes it possible to identify exactly where this component is located within the complete large microscope illuminator.

Description of this part for the microscope.

meters:
Manufacturer: Carl Zeiss Jena
Designation: Apl. 1,4
Name of the mount according to the manufacturer's catalogue: Kondensoreinhänger mfl 2, Bestellnummer 301080:021.26/0
Name of the condenser according to the manufacturer's catalogue: Aplanatischer Kondensor 1.4 mo / ms (applies only to the upper optical part)
Name of the condenser according to the manufacturer's catalogue: Kondensor hoher Lichtstärke mit Vorschaltsystem (applies to the entire module)
Version: grey colour with a black upper lens. Variant with a "dot" in the name after "Apl"
Numerical aperture N.A.: 1.4
Aperture diaphragm: yes, attached to the condenser mount
Wide-field lens: yes, it can be swung out of the optical path. This is the version with the large lens in a housing (see description below)
Removable upper lens: yes, it can be rotated
Mounting diameter: the optical part (condenser without diaphragm) has a mounting diameter of 39.5 mm and can be unscrewed from the condenser mount
Operating modes: the condenser can be used both as a dry condenser and as an immersion condenser

The entire part consists of the following elements:
- upper Apl. 1,4 lens
- screw-on/removable condenser (mo / ms)
- iris diaphragm screwed onto the condenser mount
- condenser mount model mfl 2
- swing-out wide-field lens
- two centering screws

This condenser is mainly used in Carl Zeiss Jena Fluoval / Fluoval-2 fluorescence microscopes. It is optimal for use with high-numerical-aperture apochromatic microscope objectives. For precisely this reason, users often install it on Carl Zeiss Jena Ergaval and Carl Zeiss Jena Amplival microscopes equipped with apochromatic objectives (Carl Zeiss Jena Apochromat).

It is worth mentioning again that this condenser can be used in two modes:
- without immersion oil on the upper lens of the condenser. In this case, it operates as a "dry condenser" and its numerical aperture N.A. is 0.9.
- with immersion oil on the upper lens of the condenser (i.e. underneath the microscope slide). In this case, it operates as an "immersion condenser" and its numerical aperture N.A. is 1.4, allowing a very bright image to be obtained – this is important in fluorescence microscopy or when using high-N.A. immersion objectives.

During production, this condenser was available in several versions:
- with a black upper lens, a dot in the model name (Apl. 1,4) and a wide-field module consisting of a single lens
- with a black upper lens, without a dot in the model name (Apl 1,4) and a single wide-field module consisting of several lenses (including one with a very small diameter)
- with a grey upper lens marked Apl 1,4mo2 and a single wide-field module consisting of several lenses (including one with a very small diameter)
- with a grey upper lens marked Apl 1,4mo2 and a wide-field module consisting of two independently swing-out lenses, each on its own mount

I have not found any information anywhere as to whether the above-mentioned versions differ in their operation. From experience, I know that they are used interchangeably – but I do not know whether any differences in operation can actually be noticed.

Mechanically, this condenser is mounted on dovetail rails located underneath the microscope stage. In Carl Zeiss Jena Ergaval microscopes, this is a separate condenser mounting block, whereas in Carl Zeiss Jena Fluoval / Amplival microscopes, the dovetail is located on the microscope stage holder block.

The manufacturer describes this condenser as follows: "High-intensity condenser with an auxiliary system for illuminating large fields while imaging the field diaphragm. [...] The condenser of the FLUOVAL 2 can be used as a dry and immersion condenser of the highest aperture to achieve the highest possible excitation intensity. It is equipped with a switchable wide-field system that illuminates the large fields of low-power objectives while providing a sharp image of the field diaphragm in the object plane."

Description of this part for the microscope.

meters:
Manufacturer: Carl Zeiss Jena
Designation: Apl. 1,4
Name of the mount according to the manufacturer's catalogue: Kondensoreinhänger mfl 2, Bestellnummer 301080:021.26/0
Name of the condenser according to the manufacturer's catalogue: Aplanatischer Kondensor 1.4 mo / ms (applies only to the upper optical part)
Name of the condenser according to the manufacturer's catalogue: Kondensor hoher Lichtstärke mit Vorschaltsystem (applies to the entire module)
Version: grey colour with a black upper lens. Variant without the "dot" in the name after "Apl"
Numerical aperture N.A.: 1.4
Aperture diaphragm: yes, attached to the condenser mount
Wide-field lens: yes, it can be swung out of the optical path. This is the version with the large lens in a housing (see description below)
Removable upper lens: yes, it can be rotated
Mounting diameter: the optical part (condenser without diaphragm) has a mounting diameter of 39.5 mm and can be unscrewed from the condenser mount
Operating modes: the condenser can be used both as a dry condenser and as an immersion condenser

The entire part consists of the following elements:
- upper Apl 1,4 lens
- screw-on/removable condenser (mo / ms)
- iris diaphragm screwed onto the condenser mount
- condenser mount model mfl 2
- swing-out wide-field lens
- two centering screws

This condenser is mainly used in Carl Zeiss Jena Fluoval / Fluoval-2 fluorescence microscopes. It is optimal for use with high-numerical-aperture apochromatic microscope objectives. For precisely this reason, users often install it on Carl Zeiss Jena Ergaval and Carl Zeiss Jena Amplival microscopes equipped with apochromatic objectives (Carl Zeiss Jena Apochromat).

It is worth mentioning again that this condenser can be used in two modes:
- without immersion oil on the upper lens of the condenser. In this case, it operates as a "dry condenser" and its numerical aperture N.A. is 0.9.
- with immersion oil on the upper lens of the condenser (i.e. underneath the microscope slide). In this case, it operates as an "immersion condenser" and its numerical aperture N.A. is 1.4, allowing a very bright image to be obtained – this is important in fluorescence microscopy or when using high-N.A. immersion objectives.

During production, this condenser was available in several versions:
- with a black upper lens, a dot in the model name (Apl. 1,4) and a wide-field module consisting of a single lens
- with a black upper lens, without a dot in the model name (Apl 1,4) and a single wide-field module consisting of several lenses (including one with a very small diameter)
- with a grey upper lens marked Apl 1,4mo2 and a single wide-field module consisting of several lenses (including one with a very small diameter)
- with a grey upper lens marked Apl 1,4mo2 and a wide-field module consisting of two independently swing-out lenses, each on its own mount

I have not found any information anywhere as to whether the above-mentioned versions differ in their operation. From experience, I know that they are used interchangeably – but I do not know whether any differences in operation can actually be noticed.

Mechanically, this condenser is mounted on dovetail rails located underneath the microscope stage. In Carl Zeiss Jena Ergaval microscopes, this is a separate condenser mounting block, whereas in Carl Zeiss Jena Fluoval / Amplival microscopes, the dovetail is located on the microscope stage holder block.

The manufacturer describes this condenser as follows: "High-intensity condenser with an auxiliary system for illuminating large fields while imaging the field diaphragm. [...] The condenser of the FLUOVAL 2 can be used as a dry and immersion condenser of the highest aperture to achieve the highest possible excitation intensity. It is equipped with a switchable wide-field system that illuminates the large fields of low-power objectives while providing a sharp image of the field diaphragm in the object plane."