Topics

1

General / Modeling vegetation

« on: May 01, 2015, 10:17:13 PM »

Do I stand a chance in modeling the vegetation included in the below Agisoft screenshot?  I have produced a dense cloud on "high" but there is not enough feature matching occurring in the canopy. 

I know there are other posts on modeling vegetation;  I'd simply like someone to give me indication whether or not it is at all possible to produce a good-looking model of the scene, or if the veg structure is simply too complicated and shadowed. I've also included the info from the chunk so that you can advise me if I should change settings. I'm also only showing one of my flight lines in the screenshot.  I should also note that I've tried depth filter mode on mild and it hasn't helped much.

2

General / Export Textured View with Cameras Floating Above

« on: May 01, 2015, 02:28:28 AM »

Is there any way to export a view of my model with the blue camera positions hovering above it?   I could take a screenshot but would like something with higher resolution.

3

General / Model looks great, but DEM is rotated on export

« on: February 23, 2015, 09:07:08 PM »

I'm wondering if anyone can give me a simple explanation of why my DEM is coming out rotated.  The model looks great in Agisoft but I can't get it to export with the proper orientation.  I've attached screenshots of the model & DEM.

I'm assuming my problems are stemming from a lack of GCP's (which weren't collected) but isn't there some way I can force the model to export with the same ground plane as is shown in the model?

I'm also including a link to a similar post below, but in that link, the poster's problem seems to be due to having a single flight-line. My flight isn't really a single-line, but perhaps it is close enough to a single line that it's resulting in the same problem.

http://www.agisoft.com/forum/index.php?topic=1640.0

4

General / Do I need GCPs to get an accurate DEM?

« on: February 12, 2015, 03:39:22 AM »

I'm shooting with a DJI phantom vision 2 plus.  I shoot in RAW so I get GPS coordinates and altitude with each photo. 

My question seems simple: do I need GCP's to ensure accurate elevation and georeferencing? My initial outputs would seem to suggest so, but I'm looking for confirmation.  I'm able to compare the DEM outputs from Agisoft against a high-resolution lidar-based DEM.

The site is under transformation and I'd like to detect small-scale elevation changes.

5

General / Recommendations for aerial shooting of a dynamic scene?

« on: February 09, 2015, 09:03:19 PM »

My goal is to shoot a site frequently enough to detect very small-scale landscape changes. I am looking to create very accurate DEMs, within a foot accuracy if possible.  I'm particularly interested in what's changing inside of the scene - the only consistency in elevation is on the outside of the scene (see the attached photo which consists of the scene at two different time points). The width of the scene is about 265 meters/870 feet.

I'm looking for recommendations on how to shoot this site, e.g.:
1. how many flight lines?
2. what altitude for flying?
3. do I need GCPs? If so, how do I go about creating them, considering the consistency is on the edge of the scene?
4. anything else that will help yield extremely accurate DEMs.

Also, I'm shooting with a DJI phantom vision 2 plus.

Thanks!