[Elphel-support] Help on short distance focusing [SEC=UNOFFICIAL]

[XIONG, Norman]

Dear Elphel Support team,

Can you advise on how to make the picture bright enough for a short distance focus?
We have a NC353L system with a 55mm F#1.8 lens. And we need to focus on an object that is 340mm away from the lens. When I expand the aperture to make the picture bright, I can't make it focus. If I make it focus, I have to change the depth and it becomes very dark. Is there a way to improve the brightness for such a short distance focusing, such as adding a spacer to the lens system?

The system configuration:
FPS: 60
Manual Exposure: 250ms
Auto WB: OFF
Auto Exposure: OFF

Please see attached image snapshot and configuration files for detail.
Thank you.

Regards,
Norman

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