Hydroptic Forum

Member

Registered: 2022-12-13

Posts: 3

UVP6- LP Questions about detected particles in classes 1&2

Hi all UVP people, I guess I am the first person to pose a question using this forum.

We are currently deploying a UVP_LP on a glider and are looking at observations of in different classes, where can we find the corresponding sizes? (* not in the UVP manual)

Here are measurements for classes 1 & 2 :

- Is it possible size class 1 has no measured particles?
- There is a jump in values in class 2 at ~250 m , this seems like a post measurement issue ? What can help fix this issue?

here is a link to the image :
[url = https://drive.google.com/file/d/1XpIxYz … hare_link]

Administrator

From: L'isle jourdain

Registered: 2022-11-08

Posts: 24

Website

Re: UVP6- LP Questions about detected particles in classes 1&2

Dear Merav,

        UVP6 is nominal.

       Class 2 contains objects of 1px, this class is impacted by noise depending on the acquisition frequency (which changes here at 250m with your programming).
This class should not be used for science unless you think carefully about the subtraction of noise in post process.
The data sent by the glider are only used to know if the instrument works and to have an idea of the structures crossed.
The data will then be downloaded directly from the UVP6.
We are working with Alseamar to improve the data transmission and control of the UVP6.
SF

Member

Registered: 2022-12-13

Posts: 3

Re: UVP6- LP Questions about detected particles in classes 1&2

Hi Sylvain,
Thank you for the answer, where are size classes explained and their corresponding values?

Administrator

From: L'isle jourdain

Registered: 2022-11-08

Posts: 24

Website

Re: UVP6- LP Questions about detected particles in classes 1&2

Hi,

The classes transmitted by Alseamar (Glimpse software) are decoded by Alseamar. It is up to them to indicate what they are doing from what the UVP6 provides in its RS232 frames.

But in fact, we don't care because Alseamar will then download the data to do science.

SF