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Focus adjustment of the cameras with Day & Night function

Revised in January, 2023

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:

         *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.