die
Brennweite
🔭 What exactly is 'die Brennweite'?
Die Brennweite is a fundamental term from optics, particularly relevant for lenses and concave mirrors. It describes the distance between the principal plane of a lens (or the vertex of a mirror) and its focal point (Fokus), which is the point where parallel incoming light rays converge after refraction (lens) or reflection (mirror).
In photography, the Brennweite of a lens significantly determines the angle of view (Bildwinkel) and the magnification (Vergrößerung):
- Short focal lengths (e.g., 18mm, 24mm) result in a wide angle of view (Weitwinkelobjektive), ideal for landscape or architectural photography.
- Medium focal lengths (around 50mm on full-frame) roughly correspond to the human visual impression (Normalobjektive).
- Long focal lengths (e.g., 100mm, 200mm, 400mm) result in a narrow angle of view and magnify distant objects significantly (Teleobjektive), popular for sports or wildlife photography.
Die Brennweite is usually specified in millimeters (mm).
Article rules for der, die, and das
-e/-ee → almost always feminine.
There are many -e nouns, many of which are feminine, but there are also some important exceptions.
🧐 Grammar in Detail: die Brennweite
The word "Brennweite" is a feminine noun. The article is always die.
| Case | Article | Noun |
|---|---|---|
| Nominative | die | Brennweite |
| Genitive | der | Brennweite |
| Dative | der | Brennweite |
| Accusative | die | Brennweite |
| Case | Article | Noun |
|---|---|---|
| Nominative | die | Brennweiten |
| Genitive | der | Brennweiten |
| Dative | den | Brennweiten |
| Accusative | die | Brennweiten |
📝 Example Sentences
- Die Brennweite dieses Objektivs beträgt 50 Millimeter.
(The focal length of this lens is 50 millimeters.) - Man kann die Brennweite bei einem Zoomobjektiv verändern.
(You can change the focal length on a zoom lens.) - Für Porträts wird oft eine mittlere bis lange Brennweite empfohlen.
(A medium to long focal length is often recommended for portraits.) - Die Wahl der richtigen Brennweite ist entscheidend für die Bildwirkung.
(Choosing the right focal length is crucial for the image impact.)
💡 How to use 'Brennweite'?
The term "Brennweite" is primarily used in technical and scientific contexts, especially in:
- Optics (Optik): When describing lenses (Linsen), mirrors (Spiegel), telescopes (Teleskope), microscopes (Mikroskope), etc.
- Photography (Fotografie): As a key characteristic of camera lenses (Kameraobjektive) to describe the angle of view (Bildwinkel) and magnification (Vergrößerung).
- Ophthalmology (Augenheilkunde): In relation to the refractive power of the eye and the correction of visual impairments (although the reciprocal, diopter, is often used here).
In everyday language outside these specialist fields, the word is less common. People might speak more generally about "Zoom" or "Vergrößerung" (magnification) when referring to cameras.
Important Distinction: Die Brennweite is not the same as focus (Fokus) or sharpness (Schärfe). It is a fixed property of a lens (for prime lenses) or an adjustable range (for zoom lenses), whereas focusing (fokussieren) is the process of making the image sharp.
🧠 Mnemonics for Brennweite
Article Mnemonic: Think of 'die Kamera' (the camera) or 'die Linse' (the lens) – both are feminine in German, just like die Brennweite which belongs to them.
Meaning Mnemonic: Imagine light rays brennen (burning 🔥) through a magnifying glass to a point. The 'width' or distance (Weite) to that burning point is the Brennweite (focal length).
🔄 Synonyms & Related Terms
Synonyms
- Fokuslänge (focal length)
- Fokusdistanz (focal distance)
- Fokusweite (focal width/distance - less common)
Related Terms (No direct antonyms)
- Bildwinkel (angle of view): Closely related to Brennweite (short focal length = wide angle of view, long focal length = narrow angle of view).
- Dioptrie (diopter): The reciprocal of the Brennweite (in meters), describes the refractive power of a lens.
- Schärfentiefe / Tiefenschärfe (depth of field): The range in the image that appears sharp; influenced by Brennweite, among other factors.
😄 A little joke
Warum nehmen Fotografen ihre Kamera mit ins Bett?
Damit sie auch im Schlaf die richtige Brennweite für ihre Träume finden! 😉
--- Translation ---
Why do photographers take their camera to bed?
So they can find the right focal length for their dreams even while sleeping! 😉
📜 Poem about the lens
Die Linse fängt das Licht geschwind,
ein Strahl, der seinen Fokus find'.
Der Abstand, klar und rein,
muss die Brennweite sein.
Mal kurz für weites Land,
mal lang aus Fotografenhand,
so formt sie Bild und Sicht,
im hellen Sonnenlicht.
--- Translation ---
The lens catches light so fast,
A beam that finds its focus cast.
The distance, clear and fine,
Must be the focal length's design.
Sometimes short for landscapes wide,
Sometimes long, the photographer's guide,
Thus shaping image, view, and sight,
In the bright sunlight.
🧩 Who or what am I?
Ich messe eine Distanz in Glas und Luft,
bestimme den Winkel, nicht den Duft.
Ob weit das Feld, ob nah das Tier,
ich bin entscheidend, glaube mir!
In Millimetern oft genannt,
in Optik und Foto wohlbekannt.
--- Translation ---
I measure a distance in glass and air,
Determine the angle, not the scent to share.
Whether the field is wide, or the animal near,
I am crucial, believe me, my dear!
Often named in millimeters' measure,
Well-known in optics and photo treasure.
(Solution: die Brennweite / focal length)
✨ Other Interesting Facts
Word Composition: The word "Brennweite" is composed of:
- brennen: Meaning 'to burn', referring to the Brennpunkt (focal point) where light rays concentrate and can generate heat (like with a magnifying glass in sunlight).
- Weite: Meaning 'width', 'expanse', or 'distance' here.
Physical Significance: Die Brennweite is a central physical quantity for characterizing imaging optical systems. It influences not only the image scale (magnification) and the angle of view, but also phenomena such as depth of field (Schärfentiefe) and optical aberrations (Abbildungsfehler).
📝 Summary: is it der, die or das Brennweite?
The correct article for Brennweite is always die. It is a feminine noun: die Brennweite (the focal length), der Brennweite (of the focal length), ..., die Brennweiten (the focal lengths).