In October 2025 GerBI started a cooperation with the German Optical Museum in Jena. This blog article gives insights on the cooperation and the workshop-series carried out in november and december 2025.

Background to the GerBI/D.O.M. Cooperation

What makes a microscopy exhibit truly engaging? This was the guiding question for a recent workshop series where colleagues from German BioImaging (GerBI) and the Deutsches Optisches Museum (D.O.M.) came together to share ideas, experiences, and practical solutions. The focus was an open exchange about which specimens could captivate museum visitors of all ages while remaining scientifically robust, durable, and easy to implement.

Origins of the Collaboration

The story began at the Zeiss Großplanetarium in Berlin, celebrating the microscope’s 400th anniversary. GerBI provided hands-on microscopy experiences for visitors, which sparked a conversation between GerBI member Silke Tulok (CFCI, TU Dresden) and Maria Dienerowitz (Ernst Abbe Hochschule, Jena and responsible for interactive exhibits at D.O.M.) about the ambitious planning of the exhibition concept.

The museum will undergo a full remake before it reopens in 2028. The makeover includes an extension of the historic building, a new didactic approach (“Let me do it, and I will understand”), and a whole floor dedicated to microscopy. The museum wants to attract visitors with a hands-on exhibition where they can use microscopes and learn how different developments have made various aspects of our world visible. Key aspect is edutainment, as Timo Mappes, the director of the museum, explained to the community during a GerBI-Chat. The concept of the museum was published recently as “Deutsches Optisches Museum – edutainment for optics & photonics”. He is in the field for more than a decade and holds patents for edutainment even in sales processes for optics.

The Role of the GerBI Community

To make the visitors’ experience as interesting and engaging as possible, the setup of the microscopes and the samples presented there is crucial. For unexperienced users, it can be very difficult to see something through a microscope. Also, the samples should be selected not only for their intrigue but also for their robustness, durability, and ease of creation. Here comes the GerBI-Community into play! The GerBI-Community gathers numerous experts on microscopes, samples, and many members work with unexperienced users to explain and accompany them into the world of microscopy. They work with various classical and extravagant samples and know their strengths and weaknesses well. Furthermore, members of GerBI-Community are heavely involved in many outreach and science communication projects like WDR’s Türen auf mit der Maus, since several years. So, there’s a big expertise and knowledge within the GerBI-Community in teaching microscopy and basics of optics to the public with exciting experiments. In the best sense of GerBI, where the community is formed around enriching each other’s expertise through exchange and learning together, we set up a workshop series to bring together the D.O.M. team and GerBI community members.

Workshop Structure and Main Discussion Points

After an introductory GerBI-Chat where the D.O.M. team introduced the concept of the new museum and explained the cooperation details, the workshop series began. The online-held workshops were structured around specific exhibit stations, including historic Leeuwenhoek microscopes, droplet microscopes, and lightfield-darkfield comparison setups. Key discussion points included technical implementation challenges, user-friendly visitor experience, didactic strategies, and sample selections. Many GerBI members who were unable to attend in person have expressed strong interest in the workshop’s outcomes. This article summarizes the key findings and discussions, with the hope that they will inspire future exhibits and educational concepts.

Key Findings by Exhibit Station

Leeuwenhoek Microscope: Safe and Engaging Samples

Transparent insect wings, such as those from bees or wasps, were proposed as suitable samples for the Leeuwenhoek replicas due to their visibility under low magnification. However, the sharpness of the sample needle raised concerns about safety and usability. A potential solution could be to blunt the needle or use a protective cover. The dandelion seed head was identified as a popular but challenging sample due to its need for careful mounting. Pre-prepared sample sets from suppliers like Lieder (Johannes Lieder GmbH & Co. KG) were recommended for consistency and durability. To guide visitors, an image demonstrating the correct viewing distance could help ensure a successful experience.

Droplet Microscope: Challenges and Alternatives

The idea of using a droplet microscope to observe live microorganisms from a hay infusion was discussed, and could be inspired by Stephan Junek’s YouTube channel on pond microscopy. However, several challenges were identified:

• Optical complexity: Maintaining a constant surface curvature in a water droplet is technically demanding.
• Organism movement: Microorganisms in a hay infusion move too quickly for stable observation, even in structured environments like IBIDI channel slides.
• Evaporation: The droplet’s rapid evaporation poses a practical limitation.
• Sample alternatives: Non-living samples, such as fibers or hairs, were suggested to simplify the setup.
• Alternatively the microscopical examination could be carried out in a capillary, containing a life sample.

The core question remains whether live samples are necessary or if static alternatives could achieve the same educational value.

Phase-Contrast Microscope: Drosophila Giant Chromosomes

Drosophila giant chromosomes were highlighted as an excellent sample due to their clear structural visibility through a phase contrast microscope. Experts among the workshop participants were identified as valuable resources for preparation techniques. Also, sourcing samples from Carolina Biological Supply was suggested, though caution was advised regarding the thickness of cover glasses. Lieder was again recommended as a reliable supplier for high-quality preparations

Darkfield Microscopy: Blood Smears and Alternative Samples

Blood smears were discussed as a striking sample for darkfield microscopy, though their short lifespan (a few days) presents a challenge. Fixation or thickening could extend their usability, but these methods alter the sample’s appearance. Unstained lily-of-the-valley stems were proposed as an alternative, as they reveal intricate structures in darkfield that are invisible in brightfield. Fingerprints were considered but deemed potentially too large for standard setups, with no prior experience available to confirm their suitability. The group agreed that snowflakes would be fascinating but not easy to fixate. Different approaches and practices for fixating snowflakes were discussed and considered as successful enough to potentially use them for the exhibition.

Comparison Microscope: Selecting Exciting Samples

The primary question for the comparison microscope was: “What is the most exciting sample?” Key criteria included biological relevance, exchangeability, and the ability to reveal new details at different magnifications. Proposed samples included:

• Feathers and butterfly wings (e.g., Ochsenauge), which display intricate structures at varying resolutions.
• Diatoms, which can be pre-sorted for consistency.
• Drosophila wings, which are symmetrical and allow for direct comparison between two sides.
• Histological sections stained with hematoxylin-eosin (H&E), which are durable and widely used in medical contexts.
• Chloroplasts were also suggested as a sample where structures become visible under specific conditions.

Spherical Lenses: Transparent and Striking Samples

For spherical lenses, samples needed to be transparent and visually engaging. Proposals included:

• Camembert cheese, though its longevity was questioned.
• Ticks, though engorged specimens are impractical for slides; displaying them in tubes alongside the exhibit was suggested.
• Head lice and nits, available as pre-prepared slides.
• Flower samples, such as dandelion seed heads, which are relatable but require careful selection for transparency.
• Trichinae, which are easily recognizable under low magnification.

The goal was to create samples that demonstrate the interplay between light and dark, emphasizing the need for different illumination techniques.

Comparing Single-Lens and Compound Microscopes

The exhibit aimed to compare single-lens and compound microscopes, requiring samples that work well at low magnification while offering strong contrast. Suggestions included:

• Cross-sections of LAN cables or fiber optics, which reveal internal structures with minimal color.
• Abstract patterns or microphotographs, such as banknotes or the German federal eagle, though transparency was a concern.
• Picasso’s *Dove, where small details (e.g., leaves in the bird’s beak) become visible only at higher magnifications.
• Snowflake imprints, though natural snowflakes melt; artificial replicas were proposed as an alternative.

The exhibit’s design included visualizing the light path to help visitors understand the difference between simple and compound microscopes.

Slit Viewing and Diffraction: Demonstrating Light Effects

For slit viewing, the idea of using one’s own eyelashes to create diffraction patterns was explored. Diatoms with their glass-like skeletons were suggested as a sample to demonstrate diffraction effects. The exhibit could also illustrate how aperture size affects the viewing angle and diffraction patterns.

Illumination Techniques: Brightfield and Darkfield

This exhibit focused on demonstrating illumination techniques in microscopy at optical workstations, such as brightfield and darkfield. Proposed samples included:

• Diatoms, which reveal intricate details when contrast is enhanced.
• Textile fibers, such as nylon stockings, which are easy to observe and relatable.

Explaining Köhler Illumination and Historical Context

The exhibit aimed to illustrate the principles of Köhler illumination and the role of diaphragms in adjusting contrast. A historical film about the collaboration between Abbe and Zeiss, with them as actors, was mentioned as a supplementary resource.

Additional Ideas and Future Educational Concepts

While chatting many additional ideas popped up, raving about historic scientific drawings and samples. Ideas about implementing drawing workshops in the future educational concept or using original slides from Hilde Mangold’s gastrula organizer experiments (Spemann laboratory, Nobel Prize 1935) as a way to compare historical and modern imaging techniques were discussed.

Whiteboard-notes from the first workshop

The workshop’s central insight can be distilled as follows: The most effective exhibits often combine surprise with scientific precision. Whetherthrough everyday objects, classic specimens reimagined, or historical connections, the challenge lies in sparking curiosity without compromising scientific depth.

(Whiteboard-notes from the first workshop)

The next steps will involve refining sample selection, addressing technical challenges, and ensuring the exhibits are durable and user-friendly. Next opportunities to get involved in the cooperation will be when the samples will be prepared and the didactic implementation (e.g. info-boards, explanations) is started. Planning for follow-up events is already underway. Those with ideas or experiences to contribute are warmly invited to reach out to the workshop organizers. One thing became clear: The search for the perfect exhibits is an ongoing, collaborative process and we’re delighted to be a part of it.

We will keep you updated!