Show Posts

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.

Messages - Arie

Pages: 1 2 3 [4] 5 6 ... 9
General / Re: Negligible GPU usage on Alignmnet.
« on: August 13, 2020, 09:04:01 PM »
I just tested it and on my system, GPU usage jumps between 0-37% during feature detection (GPU-Z).
Images and project files on 2x 1TB Raid0 Samsung 970 Evo Plus, GPU 1080TI, CPU 3960X.
Hope that helps?!

General / Re: wrong UTM! i have to recalculate all from scratch!?
« on: August 11, 2020, 09:40:08 AM »
i'm not sure if you can just change it in Agisoft but it's very easy to do in GIS. Just reproject the raster to 34N.

General / Re: Thermal Orthomosaic Workflow
« on: May 15, 2020, 05:47:06 PM »
I just remembered that I also had difficulties finding any information on the sensor size, which is needed for calculating the pixel size. But with the information on the field-of-view in combination with the focal length, you can calculate the sensor size. There are some online calculators for that.

General / Re: Thermal Orthomosaic Workflow
« on: May 15, 2020, 05:38:40 PM »
You should be able to calculate it yourself: sensor width (mm)/ horizontal resolution (pixel) and sensor height (mm)/vertical resolution (pixel).
Or just check whether Flir Tools shows that in the EXIF data.

I would be suprised if ERDAS doesn't have the capabilities to correct this effect but I haven't used it in many many years.
But as s.k. said, you could just use "simple" image processing software to manually correct this.
All the best.

Hi Robert,
do you mean correcting the bright stripe on the left? AFAIK, this is not possible with the Delighting tool since it's designed for quite a different use case.
s.k. gave you a good answer on stackexchange.

General / Re: Low quality texture, large drone model
« on: May 15, 2020, 03:26:13 PM »
Hi Tim,
the 4096x4096 texture size is most likely too small for the size of this model. I quite frequently use texture sizes of 16384x16384. What is your ground-sampling distance of the original images?
Unfortunately, I can't comment on the tiled model since I have no experience using those. But I am quite suprised to see "0.6mm/pix". What's up with that?

General / Re: Thermal Orthomosaic Workflow
« on: May 15, 2020, 03:19:04 PM »
It's been awhile since I last worked with thermal images but I remember having to input some camera calibration values, such as sensor size, pixel size etc., before running the alignment. If I remember correctly, the pixel size wasn't square but varied between length and height.
Good luck!

General / Re: Help filling a hole in my ortho
« on: May 15, 2020, 03:13:20 PM »
just as a quick thought: Why don't you just use the "Fill nodata" tool from the processing toolbox to interpolate the hole in QGIS?

General / Re: Bad render in Blender, not like agisoft...
« on: May 11, 2020, 09:11:48 AM »
Hi Dyst,
could it be that the main difference between the two is that Agisoft uses a shadeless approach for displaying textured meshes while in Blender you see more of the surfaces geometry due to lighting?

General / Re: Bad Stitching - What causes this?
« on: December 28, 2019, 02:42:05 AM »
Hey ashalota,
why are you dividing the flight lines into separate chunks if you have enough overlap between the lines and GPS tags? What do you mean by "varying long flight-lines"?

In general, I would recommend to align all the images in one chunk. Since your images have GPS coordinates, they should be roughly pre-aligned, reducing the processing time quite a bit in comparision to deactivating preselection altogether ( make sure to select Reference preselection in the alignment dialog).
For creating a dense cloud/ mesh and DEM/ Orthomosaic you can use the "split in chunks" script ( This reduces the memory required for processing and will ensure a seamless transition between the separate orthoimages.

Are you using a RTK-GNSS? And don't you have ground control points?

General / Re: 3D modeling of am object from a CT scan
« on: December 28, 2019, 02:01:56 AM »
Hey oritik,
Alexey is right, the images are definitely not suitable for typical photogrammetric processing pipelines based on SFM/MVS.
Creating 3D-models from CT-scans is actually fairly easy and there are a lot of different programs for this. I personally had some good experience using 3D Slicer, which is free and open source.
Do you have the original DICOM files? That's the standardized file format for CT scans, using these makes processing even more straight-forward.
Drop me a line in case you need more tips.

General / Re: Lens question
« on: April 17, 2019, 12:14:46 PM »
Hi pbourke,
the focal length of a lens can change when adjusting the focus. This is a well-known effect named "focus breathing".

In general, I usually use only manual focus, i.e. I stay at a constant distance to the object-of-interest. If I need some additional close-up shots, where I am required to refocus, I create a second calibration group for the images with the adjusted focus in Agisoft to compensate for the change in focal length.

Hope that helps.
All the best,

General / Re: Investigating Alignment Parameters
« on: December 19, 2017, 11:55:01 AM »
Additonally, wouldn't the electronic shutter also influence the results regarding the reprojection error (i.e. rolling shutter effect)?

General / Re: Method For Masking Out Sharp Pixels?
« on: November 14, 2016, 09:59:39 AM »
Hi DTFrontMan,
when dealing with depth-of-field issues I often use Photoshops CCs feature "Select Focus Area". It automatically selects unsharp portions of the image, which can be used as a mask for texturing in Photoscan.
Most of the time, this works quite great!

Pages: 1 2 3 [4] 5 6 ... 9