Focus adjustment of the cameras with Day & Night function

Revised in December 2025

This article explains how to avoid the out-of-focus blur when the camera switches between color mode and black & white mode.

Applicable models:

Cameras with “auto back focus (ABF)” or “auto focus (lens AF)” in addition to the “Day & Night” function

Phenomenon:

Out-of-focus blur occurs on the image after the mode is switched from color to black & white / black & white to color.

Cause of out-of-focus blur:

Focus adjustment by the Auto focus does not operate properly due to the following conditions:
- Low light conditions
- A spot light is captured on the image
- The captured subject has less contrast

Countermeasure for 1:

Refer to the Focus behavior of Preset, Fix, and Auto carefully and select an appropriate focus behavior for [Adjustment method]*, to avoid out-of-focus blur in your environment.

*Go to [Image/Audio] > [Image quality] > [Zoom/Focus adjustment] (or [Back focus] or [Focus])> [Setup>>] > [Adjusting method]

Focus behavior of Preset, Fix, and Auto:

Adjustment method	The focus behaviors	The focus position when switching to:
		Color mode	Black & white mode
Preset	The focus moves to the position adjusted in each mode when switching between the color mode and the black & white mode.	The focus moves to the position adjusted by ABF(AF) or manually in color mode.	The focus moves to the position adjusted by ABF (AF) or manually in black & white mode.
Fix	The focus is fixed on the same position in both color mode and black & white mode.	The focus stays on the position most recently adjusted by ABF (AF) or manually, in both color mode and black & white mode.
Auto	The focus position most recently adjusted by ABF (AF) or manually in color or black & white mode is stored as an original position. When the mode is switched from the one with the adjusted original position to another: -> The camera automatically adjusts the focus. When the mode is switched back: -> The focus returns to the original position.	When the original position is stored in color mode
		The focus moves to the position adjusted by ABF (AF) or manually in color mode.	Auto focus is automatically performed.
		When the original position is stored in black & white mode
		Auto focus is automatically performed.	The focus moves to the position adjusted by ABF (AF) or manually in black & white mode.

Setting procedures:

Select the focus adjustment procedure from [A] Preset, [B] Fix, and [C] Auto.
*[A] - [C] listed in recommended order

[A] Preset (Recommended)

"Preset" adjust the focus to the each configured position when switching between color mode and black & white mode.

Setting procedure of [A] Preset

1. Select "Preset" for [Adjusting method]

2. Execute [Auto focus] or [Manual focus adjustment] in color mode during daytime
-> The focus position in color mode is stored.

3. Execute [Auto focus] or [Manual focus adjustment] in black & white mode during the nighttime*
-> The focus position in black & white mode is stored.

*When you cannot adjust the focus during the nighttime:
Go to the [Image quality] window, click the [Setup>>] button of [Image adjust].

Select "On(IR Light On)" or "On(IR Light Off)" for [Day & Night(IR)] to force switch to the black & white mode, and then adjust the focus by executing [Auto focus] or [Manual focus adjustment].

After adjustment, switch the [Day & Night(IR)] back to the original option "Auto2 (IR Light On)" or "Auto1 (IR Light Off)".

[B] Fix

"Fix" uses the same focus position adjusted by ABF (AF) or manual focus adjustment, in both color mode and black & white mode.

Setting procedure of [B] Fix

1. Execute [Auto focus] or [Manual focus adjustment] in color mode during daytime.
-> The focus position in color mode is stored.

2. Change the [Adjusting method] to "Fix".
-> The camera will use the same focus position in black & white mode.

3. Confirm the focus accuracy during the nighttime in black & white mode.

[C] Auto

"Auto" adjusts and corrects the focus position automatically when switching between color mode and black & white mode.

Setting procedure of [C] Auto

1. Check the environment in black & white mode during the nighttime.
When spotlights such as streetlights are on the image, specify the area with [Focus area setting] to avoid the lights.

2. Execute [Auto focus] or [Manual focus adjustment] in black & white mode during the nighttime

3. Check the focus accuracy.

Note: Do not execute [Auto focus] or [Manual focus adjustment] in color mode during daytime after the step1-3 above.

High zoom bullet cameras

High-zoom bullet cameras feature Fixed Focus Shift (Normal) and Fixed Focus Shift (LPR) options. Recommended use cases for each mode are described below.
Applicable models: WV-S15701-Z3L/WV-S15701-Z3LN/WV-X15701-Z3L/WV-X15701-Z3LN/WV-S15501-Z3L/WV-S15501-Z3LN/WV-S15501-Z1L/WV-S15501-Z1LN/WV-X15501-Z3L/WV-X15501-Z3LN/WV-X15501-Z1L/WV-X15501-Z1LN/WV-X15502-Z1L/WV-X15502-Z1LN /WV-S15301-Z1L/WV-S15301-Z1LN/WV-X15301-Z1L/WV-X15301-Z1LN/WV-X15302-Z1L/WV-X15302-Z1LN

Recommended use case of [Fixed Focus Shift (Normal)] and [Fixed Focus Shift (LPR)]

[Fixed Focus Shift (Normal)]

Default setting for WV-S15501-Z1L/WV-S15501-Z1LN/WV-X15501-Z1L/WV-X15501-Z1LN/WV-S15301-Z1L/WV-S15301-Z1LN/WV-X15301-Z1L/WV-X15301-Z1LN

When focus is incorrect after switching between color and black-and-white
(while [Adjusting method] is set to Auto)
When autofocus does not work properly, such as:
- Subjects under a spotlight (e.g., streetlamps)
- Environments with heavy vehicle traffic
When zoom magnification is 10x or less

[Fixed Focus Shift (LPR)]

When using the License Plate Recognition (LPR) function
To focus on license plates that reflect the camera’s built-in IR LED light
(The focus position is shifted by a fixed amount for this purpose)

Focus behavior of [Fixed Focus Shift (Normal)] and [Fixed Focus Shift (LPR)]:

Adjustment method	Mode behavior	The focus position when switching to:
		Color mode	Black & white mode
Fixed Focus Shift (Normal)	Moves the focus by a fixed amount when switching between color and black & white modes from the last focused position. The new position is optimized for both visible and IR LED light. When the mode is switched back, the focus returns to its original position.	The most recent focus position adjusted by ABF (AF) or manual adjustment in color mode (original position).	The focus position shifted by a fixed amount from the color focus position.
		The focus position shifted by a fixed amount from the black & white focus position.	The most recent focus position adjusted by ABF (AF) or manual adjustment in black & white mode (original position).
Fixed Focus Shift (LPR)	Moves the focus by a fixed amount when switching between color and black & white modes from the last focused position. The new position is optimized for focusing on license plates illuminated by the built-in IR LED. When the mode is switched back, the focus returns to its original position.	The most recent focus position adjusted by ABF (AF) or manual adjustment in color mode (original position).	The focus position shifted by a fixed amount from the color focus position
		The focus position shifted by a fixed amount from the black & white focus position.	The most recent focus position adjusted by ABF (AF) or manual adjustment in black & white mode (original position).