Agisoft Metashape

Agisoft Metashape => General => Topic started by: njsym3 on March 26, 2020, 11:31:47 PM

Title: Difficulty of aligning photos on mixed tree forest
Post by: njsym3 on March 26, 2020, 11:31:47 PM
Hello community,

I am new to photogrammetry processing and have been having trouble creating an point cloud and orthmosaic in a tropical forest area. The trees are a mix of palms and pisonia trees amongst others, with dry conditions meaning many of the trees are spindly without leaves. I have been unable to align the photos regardless of the parameters I try. I suspect that the it is difficult to match tie points with the spindly, non-stationary canopy.

This area of the survey that we are unable to align is the most important for us as we are hoping to count the number of migratory birds nesting in the trees. Please note that we need to get an image with sufficient resolution to be able to pick out the migratory birds. I have put a down sampled version on google photos and a subset on google drives if anyone wants a further look. The links:

https://drive.google.com/file/d/1q5cOu8ftEQpm-pYJx7XJPvJRA2NZLe1U/view?usp=sharing
https://drive.google.com/file/d/1q5cOu8ftEQpm-pYJx7XJPvJRA2NZLe1U/view?usp=sharing

I am basically asking for some guidance on a few points:

1. Is this data useable for creating an orthomosaic?
2. If not is there some changes to the acquisition (i.e. flight height, only flying on perfectly still days) that would produce more useable data
3. COuld we do some kind of manual alignment with our own tie point

Thanks and I look forward to hearing from anyone with experience... much appreciated
Title: Re: Difficulty of aligning photos on mixed tree forest
Post by: bisenberger on March 28, 2020, 01:14:49 AM
You might want to check out the tips in this faq:

https://agisoft.freshdesk.com/support/solutions/articles/31000149338-aerial-survey-tips-with-a-fixed-wing-uav-





Title: Re: Difficulty of aligning photos on mixed tree forest
Post by: njsym3 on March 31, 2020, 01:26:36 AM
Thanks for the response... I think this pretty well tells me what I need.... I wish I had seen it earlier.

Neil