# focus hold button function

> button on a lens that fixes the focus point while being pressed

**Wikidata**: [Q133503132](https://www.wikidata.org/wiki/Q133503132)  
**Source**: https://4ort.xyz/entity/focus-hold-button-function

## Summary
The focus hold button function is a momentary control on a camera lens that fixes (holds) the selected focus point only while the button is being pressed. It is a push-button mechanism mounted on the lens that gives temporary control over the lens focus behavior.

## Key Facts
- The focus hold button function is an instance of a push-button.  
- It is part of a camera lens.  
- Its primary function is to fix the focus point while the button is being pressed.  
- It is a momentary (temporary) control — the focus is held only during the press.  
- Aliases include: "focus hold button", "Fokushaltetaste", and "Fokushaltetastenfunktion".  
- The related class "push-button" is a simple mechanism with an area that can be temporarily pushed down to control a device.  
- The related push-button class entry has 26 sitelinks (sitelink_count: 26).  
- The Wikidata description: "button on a lens that fixes the focus point while being pressed."

## FAQs
### Q: What does the focus hold button function do?
A: It fixes the selected focus point on the lens while the button is being pressed. The hold is temporary and applies only for the duration of the press.

### Q: Where is the focus hold button located?
A: The focus hold button function is implemented as a button on a camera lens.

### Q: How is the focus hold button operated?
A: It is operated by pressing the button; the focus is held while the button remains pressed and releases when the press ends.

### Q: Is the focus hold button a permanent lock?
A: No. It is a momentary push-button control that holds focus only while being pressed.

## Why It Matters
The focus hold button function provides photographers with immediate, temporary control over lens focus. By fixing the focus point only while pressed, it enables short-term stabilization of focus selection without changing persistent focus modes or settings on the camera. As a simple push-button mechanism mounted on the lens, it gives direct, tactile control at the point of operation. This design supports quick, on-demand interventions during shooting, allowing users to maintain a chosen focus point for the exact moment they need it without altering other autofocus behavior. Because it is implemented at the lens level and operates only during the press, the function integrates with existing camera focus systems while offering a lightweight and reversible way to manage focus in-the-moment.

## Notable For
- Being an instance of a push-button type control specifically integrated into camera lenses.  
- Providing momentary (temporary) focus hold that only applies while the button is pressed.  
- Being described succinctly on Wikidata as a "button on a lens that fixes the focus point while being pressed."  
- Having language-specific aliases, including German forms "Fokushaltetaste" and "Fokushaltetastenfunktion."  
- Implementing a simple push-button mechanism (the related push-button class is defined as a simple temporary push control).

## Body
### Definition
- The focus hold button function is a button on a lens.  
- It fixes the focus point while being pressed.  
- It is an instance of the push-button class.

### Function
- The button holds the lens' selected focus point.  
- The hold is active only during the physical press.  
- Releasing the button ends the hold.

### Mechanism
- Classified as a push-button mechanism.  
- A push-button is a simple mechanism with an area that can be temporarily pushed down to control a device.  
- The lens-mounted focus hold button follows that momentary push action model.

### Location and Classification
- Part of a camera lens.  
- Instance of: push-button.  
- The function is implemented on the lens housing where it can be operated by the user.

### Aliases and Names
- English: focus hold button.  
- German: Fokushaltetaste; Fokushaltetastenfunktion.

### Related Entries
- Related class: push-button — described as a simple mechanism with a temporarily pushable area.  
- Related push-button entry has a sitelink_count of 26.

### Source Description
- Wikidata description (concise): "button on a lens that fixes the focus point while being pressed."