Messages

46

General / Re: Optimize camera alignment creates larger errors

« on: March 02, 2018, 01:28:57 AM »

Hi SAV
Here is the report PDF. https://www.dropbox.com/s/79k37dhovyd1czt/Chopsticks_Photoscan_report.pdf?dl=0

My GCPs are based on an existing orthophoto with spatial accuracy is +-2m (@ 90% confidence). My Z values are estimated from 5m contours generated from LiDAR.

I have tried unchecking all cameras, but the Optimize Cameras process still makes the sparse cloud go haywire.
I had GCP 8 unchecked.

Perhaps I should run 'Model>Edit > Gradual Selection' before trying Optimize? I left that completely out as nearly all points were 'bad' - probably due to the big tree lean on the edge of photos (low altitude drone, wide angle lens).

My final orthophoto isn't positioned as well as I would like, but the tree lean is all gone.

47

General / Optimize camera alignment creates larger errors

« on: March 01, 2018, 06:14:52 AM »

Project is to make an orthophoto from DJI photos of a forest.
I aligned photos using the Reference option (longitude/latitude in EXIF).
To get all photos to align, I had to set Key Pt & Tie Pt options to 0.
I have 16 good precision GCPs, although I removed "8" as it had the biggest error.
A few photos had markers that I couldn't position due to tree lean/displacement, so I left those with grey symbol.

When I do Optimize Camera Alignment, my sparse cloud goes crazy, and my x,y,z errors get much worse. (The dialog box showed all options checked except Fit p3, Fit p4, rolling shutter.)

I have settled for creating the orthophoto without doing the optimize. It's not perfect, but still useable.
(Before optimize & after optimize (angled to show problem) images of sparse cloud are attached).
version 1.3.4.5067

48

General / Re: Work Flow for GCP

« on: February 22, 2018, 01:19:22 AM »

[...edit...]
3. Convert GPS coordinates of your geotagged images (WGS84) to match the coordinate system of your ground control points (GCPs) which will be imported later. Note that the altitude information stored in the EXIF data of imagery acquired by DJI drones is the relative altitude from the point of take off and not the absolute/real world altitude. Here are 3 ways to fix this issue: http://www.agisoft.com/forum/index.php?topic=4986.msg38769#msg38769
[...edit...]

I'm currently having a problem aligning a set of 500+ UAV photos over a forest.
Does the above step#3 mean than I need to somehow replace the longitude/latitude EXIF date with the coordinate system that my (very accurate) GCPs use? If so, how do I do that?
Also, is the altitude data used by Photoscan? Should I remove those?
Thanks!

49

General / Photo rotation before or after alignment?

« on: February 16, 2018, 07:53:14 AM »

I have many aerial photos. About half of them were taken at 180 degrees from the others.
The align photos process completed with everything aligned correctly.

But now I'm having trouble positioning my control points, so are having to rotate the photos inside Photoscan.
I think I will be able to get my errors down to acceptable levels. I haven't finished yet though.

Do I need to repeat the align photos process after this? I'm wondering if my tie point cloud is faulty and misleading, and will affect the final orthomosaic.

50

General / Re: Dimension Agsoft

« on: September 11, 2017, 01:29:38 PM »

https://www.computerhope.com/issues/ch001356.htm

51

Bug Reports / Re: geoid sign seems to be wrongly applied

« on: September 11, 2017, 01:27:29 PM »

I'm flying a DJI Mavic Pro and indeed it outputs what me may call "GPS altitude" but today I discovered that the height of the take off point I was using (in clear view of the sky with virtually no multipath) has "errors" of more ( ) than 100m between two flights separated 4 days, that is obviously unacceptable for photogrammetric processing.

I wonder if the bigger than expected altitude variation was caused by the recent CMEs and/or high level proton storm from the sun (but that was only in the past couple of days)?

52

General / Re: Export GeoTIFF, modify with Lightroom & than export to KMZ

« on: August 29, 2017, 12:54:15 AM »

See my post about creating hi-res KMZ files using G-Raster (very cheap).
http://www.agisoft.com/forum/index.php?topic=7365.msg35447#msg35447

53

General / Re: Orthomosiac aerial image exported as a kml file.

« on: July 10, 2017, 03:59:52 AM »

http://moagu.com/?page_id=155 You want G-Raster version 6.2, as there was a problem with 6.3.
It takes a geotiff or similar, makes it into a series of tiles, then packs it up as a single KMZ file.

54

General / Re: Orthomosiac aerial image exported as a kml file.

« on: July 08, 2017, 04:03:26 AM »

We use the paid (it's cheap) version of G-Raster to take a high resolution orthophoto over to Google Earth Pro.

55

General / Re: Choice of photo sequence used in orthophoto

« on: July 03, 2017, 01:02:23 AM »

The only 'meta' information I can see is formatted like the following example, which I found in the doc.xml inside
 MyProjectName.files\0\0\frame.zip
<property name="Exif/Make" value="Canon"/>

so perhaps camera.meta["priority"] = 1 would have to be formatted something like
<property name="priority" value="1"/>

That is just my guess. Perhaps Alexey will correct this if it is wrong.

56

General / Choice of photo sequence used in orthophoto

« on: June 29, 2017, 04:55:48 AM »

I had four overlapping photos.
The orthorectification has used the photo which had the worst quality, on top of better ones. I wish the three better photos to be used on top, and the bad one to be used underneath - to fill in gaps if they exist.
Is this possible to do?

57

General / Re: Lastest Agisoft installer: Windows flagged as harmful?

« on: May 23, 2017, 05:07:09 AM »

Uploaded to virustotal.com, to scan with multiple malware scanning engines.
Results:
File name:    photoscan-pro_1_3_2_x64.msi
Detection ratio:    0 / 54  (<--- than means no problem found by 54 different scanners).
Analysis date:    2017-05-22 20:19:27 UTC ( 5 hours, 44 minutes ago )

I didn't try the 32-bit installer.

58

General / Re: Export Orthomosaic as JPG - No location data?

« on: May 20, 2017, 05:41:10 AM »

ECW can hold location data, and is maybe half the size of a jpeg, with similar quality.
I'm not sure of the best way to get the data in from a worldfile though.

59

Bug Reports / Re: "Error reading project"

« on: May 18, 2017, 09:24:42 AM »

Hello VanForester,

In the doc.xml you can see the relative paths to the certain elements of the project, so you can just check, if there are such folders and files inside. If not, then remove the corresponding line from doc.xml.

Very useful to me today, thanks Alexey.
Managed to easily fix a small (fortunately) project after my point cloud zip file was corrupt. (Was named with .tmp at the end).
Version 1.3.1 Win10 64-bit.

60

Bug Reports / Re: Specification of Shape files, so I can see on model

« on: May 02, 2017, 06:49:32 AM »

Thanks Alexey,
Console command worked after I deleted the shapefile, reimported it & issued the command again.

Saved for future reference, as I'll need to do this when PRJ files are incomplete.
In fact I've saved a corrected PRJ file to use as a TEMPLATE. That gives me another option.