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91
General / Re: Placing markers increase camera erros after calibration
« Last post by Paulo on July 23, 2021, 06:44:01 PM »
hi aag_frei,

it seems the drone flew always facing in same direction (yaw = 20 deg) i.e. not turning when changing flight line (going forward on 1st line, backward on 2nd line, etc..) and this causes heavy correlation between internal parameters (f,cx,cy) and external  orientation....see https://www.agisoft.com/forum/index.php?topic=9820.msg58262#msg58262.
From https://agisoft.freshdesk.com/support/solutions/articles/31000158119-what-does-camera-calibration-results-mean-in-metashape- tutorial:
Quote
We recommend to review the adjusted values for the cx, cy, b1 and b2 parameters in the Camera Calibration dialog. If the values for the parameters are too large (hundreds or more for cx, cy and tens or more for b1, b2), then it may be reasonable to re-align the data set having these parameters fixed.
Usually the values for cx and cy are around a couple dozens of pixels (or less), as the values are measured from the center of the image. And the values for b1 and b2 are usually not more than a few units.
If the values are hundreds or even thousands - it indicates that the estimation of the calibration parameters is probably incorrect. Sometimes it may be related to the flight mission specifics, for example, if the camera is not rotated by 180 degrees on the neighboring flight lines. You can try to fix the mentioned parameters and re-align the data set having "adaptive camera model fitting" option disabled.
If you could show the adjusted camera parameters in Camera Calibration window to see if you have some unrealistic values for cx, cy....

You may have to fix f,cx,cy in initial alignment to get a result.... and then in final adjustment you may unfix....

Also in final optimizaton, I would deselect all cameras as their accuracy (consumer grade airborne GPS) is not great compared to markers and DJI drones have a history of storing wrong altitude (from your info, the drone flew around 25 m AGL which is very unlikely as it corresponds to 0.6 cm GSD).... But if markers were correctly determined using Leica dGNSS via SAPOS RS or VRS, you should get final errors on markers at the cm level not the dm or m level from your current results...

Hope maybe this gets you further along...

PS. you can look at camera.photo.meta["DJI/RelativeAltitude"] to see at what Altitude AGL the project was flown... In example attached the drone was flying at 120 m AGL with an altitude ASL of 138 m....
92
Bug Reports / Re: Refine Mesh error 1.7.3 12743
« Last post by eltama on July 23, 2021, 06:26:38 PM »
Driver studio 471.41, I tried without success to compute with only one GPU
93
General / Re: Placing markers increase camera erros after calibration
« Last post by aag_frei on July 23, 2021, 05:34:54 PM »
Hi! Thank you for your help! It actually works perfectly fine when I align the cameras at lowest accuracy. However, the problem persists when i align the pictures at high accuracy.

General setup:
-DJI Mavic 2 Pro, Camera calibration f fixed, in the Reference Pane Yaw, Pitch and Roll fixed to 20, 0, 0 (because it adds some strange values for yaw if I don't set it up manually).
-14 GCPs, measured with a Leica dGNSS via Sapos.
-Reference Accuracy: Markers 0.1m, Cameras 4m and 10°.

Workflow:
1. Add images to chunk, fix Yaw (20, from our flight plan), Pitch (0 - straight down?), Roll (0).
2. Fix f in camera calibration (4256).
3. Add & place markers.
4. Align photos with/without markers checked (I tried both, but both results in high errors). Without markers, only the cameras, the error for the cameras is fine. When checking the markers and actualizing, the errors of the cameras increase.
5. Optimize cameras... but same error.

Attached screenshots:
1. Reference pane without markers
2. Reference pane with markers
3. Errors without markers
4. Errors with markers

94
General / Re: Color can affect quality?
« Last post by wojtek on July 23, 2021, 04:17:52 PM »
The parts with lesser results probably have less overall noise and thus the reconstruction is not as accurate? Color per say should have no impact on any of it I think.
95
General / Color can affect quality?
« Last post by OZDF on July 23, 2021, 01:14:30 PM »
Hi Everyone,
I have a question: during my works I noticed that some colours can affect quality of the final mesh. I am working on a wooden sculpture (not painted, so the color is the classic wood color), and the basement is a very colourful red.
Near the basement the mesh is really distorted and the shape of the basement is full of crazy bubbles.
I tried to desaturate the reds and I obtained a little better result, but not sharp as the rest of the sculpture. That's really strange because the source pictures are good and allow me to obtain good results on every other part.
96
General / Re: What does Metashape do with fiducial marks?
« Last post by adehecq on July 23, 2021, 09:55:24 AM »
Hi PRobert1968,

Sorry for the slow reply, but I don't get any notifications when I get a reply on the forum and I don't come often.
I think what you are talking about (finding tie points between aerial images and modern basemap) is different from the issue I raised. In my case, I have 4 fiducial markers, that I can use to correct distortions of the film introduced during the acquisition and scanning. Usually an affine transformation is sufficient, but in that specific case, I had to use a projective transformation. It does not seem to be handled well by Metashape and I was wondering if this is something that could be improved.

I work on Bolivian aerial images. I'm based in Europe.

Best,
Amaury
97
Hello neo571,

Would it be possible to share the example of problematic images to support@agisoft.com? You can use any convenient file transfer service to send the data to us.
98
General / Error when trying to align a stereoscopic pair with satellite images
« Last post by neo571 on July 23, 2021, 05:09:58 AM »
I am following the tutorial to adjust a stereoscopic pair with Pleiades and Spot satellite images, the same message always appears "Infinitive values in tranform are not allow".

I compare the Pleiades and Spot rpc files with the Ikonos, they are different, when I import the Pleiades and Spot images they don't have the east and north coordinate information.

I have read the photocontrol points but it does not allow to align and the message continues to appear and does not produce the tie points.

I appreciate any help.
99
General / Re: Auto detect GCP tolerance
« Last post by _danny_ on July 23, 2021, 01:35:48 AM »
Does anyone have any thoughts on this? ^^ Seems like a simple question, but none of the posts about this topic on here ever get a straight answer!
100
Bug Reports / Re: Refine Mesh error 1.7.3 12743
« Last post by Alexey Pasumansky on July 22, 2021, 11:18:13 PM »
Hello Elmar,

Which NVIDIA driver version is installed on your machine?
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