Problem on data range scale with multispectral pictures on version 2.2

[Dronisimo]

Hello,

I downloaded today the latest version from the site (version 2.2.0 build 19890) and on the scale visual data of the multispectral values I have a wrong data range. Before, I was on the version 2.1, and I didn t have this problem with same project. I checked some other projects and it s the same problem. As I remember I had maximum values 1 and minimum values -1. Now it s below -1 and and the minimum value from the raster calculator it does not get -1. It s something weird that I don t understand what's going on, that s why I believe it s a bug? I have taken a screenshot to show the problem. Has someone detected this or know where could be the problem?

Many thanks in advance

Regards

[olihar]

What formula are you using?

[Dronisimo]

(B4 - B2) / (B4 + B2)

I ve attached a screenshot of the raster calculator. But in previous version I didn t have this problem, I believe it was 2.1.4

[olihar]

And how are you calibrating the dataset?

[Dronisimo]

I don t have a calibration panel. I use a DJI Mavic3M and I only use the sunlight sensor checking the case when I have clouds. If it s sunny all the flight, with no clouds, I don t use the sunlight option, I just convert the coordinate system and then, align pictures, gradual selection, optimise cameras, point cloud, filter by confidence some points, DEM and Orthophoto. And then I convert data with formulas to get NDVI and NDRE. And some other if needed. But basically that's my process. I don t know if I m wrong somewhere but I have this problem since I updated to version 2.2. I m going to downgrade to 2.1.4 as I ve seen there is an installer on the website.

I put a screenshot of the Camera calibration panel just in case there is something wrong.

Many thanks olihar for helping

Hope Agisoft team can say something about

[Alexey Pasumansky]

Hello Dronisimo,

Do you get different histogram for the same formula based on the same project, if reflectance calibration is performed in 2.1.4 and 2.2.0 versions?

[Dronisimo]

Hello Alexey,

Thank you for answering, I m very confused.. I ve installed the version 2.1.4 this afternoon and I have the same values. I tried something different, I loaded the project on a Macbook pro with the version 2.2.0, the one it s on the website and I get same values. I have to say this is a brand new PC, with windows 11 pro, with better specs than the other I had before. I installed Metashape yesterday and since, I have this problem. I remember before I had -1 / 0 / 1 on the scale visual data of the multispectral values.

Tell me if I can send you something to check or to try something else. Yesterday night I did again the same process on this brand new PC and nothing changed, that s why I thought I could come from a bug but I don t know what else to do. I can send the report if you need to verify the process or the configuration.

Hope we can find the problem

[Dronisimo]

I ve just done a new multispectral process with a small project of 209 images to make it quick but I get the same problem on the the scale visual data of the multispectral values (Minimum value is below -1 and not as the minimum value of the histogram range values. I m putting some screenshots to show the process and see if there is something wrong on the process.

[Alexey Pasumansky]

Hello Dronisimo,

So there is no difference between 2.1.4 and 2.2.0?

Also I am not sure that you can expect valid formula calculation results without performing reflectance calibration.

[Dronisimo]

Hello Alexey,

No, with 2.1.4 is the same. But I m not sure I was using the 2.1.4 before. I think it was the 2.1.1 and as I remember I could see -1 , 0, 1. I m pretty sure because chenking on the HelpDesk portal, I ve seen the scale visual data of the multispectral values in a document as I m saying(Prescription maps generation in Agisoft Metashape) as the image attached.

But what is the relation about a reflectance calibration and the showed value? It s programmed to get a calibration reflectance panel soon but at the moment, as I thought, just with the sunlight sensor of the drone it was enough for normal data.

Do you think it could be better to open a support ticket?

[Alexey Pasumansky]

Hello Dronisimo,

You just do not need to click Auto button in the Palette tab of the Raster Calculator dialog - press only Update, but keep the range as 0 - 1, then you will have the range on the orthomosaic legend as [-1;1].

[Dronisimo]

Hello Alexey,

Thank you for your answer. I couldn t reply before, I needed to redo all the process because only removing the orthomosaic and rebuilding the orthomosaic, I couldn t get the main values (-1 / 0 / 1) again. So I did it and I confirm, if I only click on the update button the range values of -1 to 1 stay on the screen. I ve been reading on the manual what the Auto button do and I understood that it gets the minimum and maximum values of the palette range, ins it? but if it s this, I believe there is a bug because it gets right the maximum value but it doesn t get right the minimum value, that's why I get under -1 when on the palette range the minimum value is between -1 and 0.

At the moment I will only push the Update button but would you think this will be fix soon?

On the other pictures I uploaded we can see what I m saying.

Hope this can help to improve this if I m not wrong.

Anyway, thank you for finding the momentary solution.

Regards