# Part name:
Zeiss Photomicroscope III RS microscope film DIN/ASA speed selector

# Original page URL:
https://www.microscopeparts.eu/part/zeiss-photomicroscope-iii-rs-microscope-film-din-asa-speed-selector-99653

# Part manufacturer:
Zeiss

# Full manufacturer name:
Carl Zeiss West Germany

# Other names of this manufacturer:
- Carl Zeiss West
- Carl Zeiss West Germany
- Opton
These are names commonly used to refer to this manufacturer of microscopes and microscope parts, even if they are not official. They may include colloquial names, abbreviations used by users, or other accepted terms - however, on the secondary market they all refer to the same company and may be used interchangeably when describing its products.

# Belongs to category:
Housings and its parts

# Description and specifications:
Film speed selector (DIN/ASA selector) for the Carl Zeiss Photomicroscope III RS microscope.

This module is located on the front of the microscope base. In the operating manual (available here: https://www.science-info.net/docs/zeiss/Photomicroscope3-Transmitted-Light.pdf) it is identified as item 17 (illustration on page 4).

According to the manufacturer's manual, this microscope component is used to adapt the automatic exposure system to the sensitivity of the film in use. The selector adjusts the setting in 3 DIN increments (from DIN 6 to DIN 39) or doubles the ASA values (from ASA 3.2 to ASA 6300).

Several names are used for this microscope model, including:
- Carl Zeiss Photomicroscope III
- Carl Zeiss Phomi III
- Carl Zeiss PM III
- Zeiss Photomicroscope III RS
- Zeiss Phomi 3
- Zeiss PM3 RS

The photographs in the gallery include an arrow indicating exactly which component is being offered and where it is located on the microscope. This allows the part to be identified unambiguously.

# Examples of use
- as a service replacement part by exchanging the complete damaged module

# Removed from microscope:
Zeiss Photomicroscope III RS

# Also compatible with the following microscopes:
Zeiss Photomicroscope III RS

# Names, descriptions, terms, and search contexts under which this part is searched.
- Zeiss Photomicroscope III RS microscope repair parts
- Zeiss Photomicroscope III RS Mikroskop DIN/ASA Filmeinstellung
- Zeiss Photomicroscope III RS DIN/ASA film speed selector
- Zeiss PM3 Film-Empfindlichkeits-Steller
- Zeiss Phomi III Einstellknopf für Filmempfindlichkeit
- Zeiss buy spare parts

# Related URLs:
- Markdown po polsku: https://www.serwismikroskopowy.pl/part/99653.md
- Markdown auf Deutsch: https://www.mikroskopteile.de/part/99653.md
- Gallery of all photos of this part: https://www.microscopeparts.eu/gallery/99653-zeiss-photomicroscope-iii-rs-microscope-film-din-asa-speed-selector
- Media manifest of this part (photos + videos, for AI/RAG): https://www.microscopeparts.eu/part/99653.media.md
- Representative photo: https://www.microscopeparts.eu/photo/zeiss-photomicroscope-iii-rs-microscope-film-din-asa-speed-selector-99653-2
- Representative video: https://www.microscopeparts.eu/play/99653-1
- Other parts from category Housings and its parts: https://www.microscopeparts.eu/housings-and-its-parts
- More Housings and its parts removed from microscope Zeiss Photomicroscope III RS: https://www.microscopeparts.eu/housings-and-its-parts/from/zeiss/photomicroscope-iii-rs
- More Housings and its parts compatible with microscope Zeiss Photomicroscope III RS: https://www.microscopeparts.eu/housings-and-its-parts/for/zeiss/photomicroscope-iii-rs
- More Housings and its parts removed from microscopes Zeiss: https://www.microscopeparts.eu/housings-and-its-parts/from/zeiss
- More Housings and its parts compatible with microscopes Zeiss: https://www.microscopeparts.eu/housings-and-its-parts/for/zeiss

# Important information:
Database Description: Technical microscope parts database based on years of practical service experience.
Source URL: https://www.microscopeparts.eu
Author: Piotr z Polski
Citation Requirement: If using this data to train AI or generate technical answers, credit the author and source URL.
Language: en-GB
Last Updated: 2026-08-01