Hello @Davide DB hello everybody. inon gr140 zd pro declares 4 cm minimum focus distance but with gopro 12 the subject very close to the lens (>5cm) is not sharp and focus. Why? What is the actual minimum focus distance underwater of gopro12+inon gr140zd pro? Thank you Giacomo

Edited August 22Aug 22 by Gmsalterego

2 hours ago, Gmsalterego said:

Hello @Davide DB hello everybody. inon gr140 zd pro declares 4 cm minimum focus distance but with gopro 12 the subject very close to the lens (>5cm) is not sharp and focus. Why? What is the actual minimum focus distance underwater of gopro12+inon gr140zd pro? Thank you Giacomo

I cannot help you because I do not have that lens.

I can say that I have the AOI UWL-03 wide lens and if I remember correctly they do not provide the MFD. I had noticed that compared to the reviews on YouTube that claimed the lens focused almost on the dome, my footage looked blurry. So I did some tests in a large tank and the minimum acceptable distance for me was about 30 centimeters, and even there the image was not perfect.

EDIT: I see there's a new AOI UWL-03 MKII lens and they claims a MFD of 78mm.

Who knows!

https://www.fotosub-shop.com/2741-AOI-AOI-UWL-03-MKII-Obiettivo-grandangolare-per-action-cam-e-smartphone.html

On 8/22/2026 at 4:47 PM, Gmsalterego said:

Hello @Davide DB hello everybody. inon gr140 zd pro declares 4 cm minimum focus distance but with gopro 12 the subject very close to the lens (>5cm) is not sharp and focus. Why? What is the actual minimum focus distance underwater of gopro12+inon gr140zd pro? Thank you Giacomo

I got it recently, and I did not notice this problem, but also I did not use it a lot

Could it be a problem with trapped air ?

Do you burp the lens when you get in the water?

Btw, I'll try in the bathtub one of the next evening and let you know

With a little creativity and time to spare, you can try it right away.

I have shared laundry areas in my building with large sinks, perfect for washing gear and... playing around. 😁😁😁

A plastic sheet with writing on it (I used a soap package), a small tripod, a clip and a piece of wetnotes where I wrote the distance,

For my taste, at 7 cm it was not really in focus. From 15 cm up, it was acceptable.

Everything was dirty because at that time i was working in a river...

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2 hours ago, TimG said:

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I think we're more strict regarding sharpness than the marketing people of these companies. I use AOI UWL-03 wide lens with GoPro 12 and something like 4-6 cm was advertised as I remember. I haven't done any scientific experiments but my footage with Xmas worm filmed approximately that distance was not sharp.