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Author Topic: swath mapping system - Zero resolution?  (Read 4039 times)

z-air

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swath mapping system - Zero resolution?
« on: May 31, 2018, 06:34:42 PM »
Good day,

A group of us have built a swath mapping system, where the lens moves side to side very quickly while flying forward in order to map a large area quickly. Photoscan pro aligns images fine, using highest setting and 100,000 key point limit, 0 tie point, but when it comes time to run the dense cloud it gives error "zero resolution". I have checked the boundary box and it is set correctly.  I'm wondering if the software does not like that some images are at a steeper angle? Images are all geo referenced. 

The data i'm running was flown in a straight line while the lens quickly scans side to side capturing an area about 7km wide. There is plenty of sidelap/overlap. It is mounted on fixed wing aircraft and we flew at 9,500' asl.

Alexey Pasumansky

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Re: swath mapping system - Zero resolution?
« Reply #1 on: May 31, 2018, 07:27:14 PM »
Hello z-air,

Can you also provide a screenshot from a side view and also the related processing log from the Console pane?

Also check the number of valid matching points for some random cameras in the View Matches dialog - what are the max numbers?
Best regards,
Alexey Pasumansky,
Agisoft LLC

z-air

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Re: swath mapping system - Zero resolution?
« Reply #2 on: May 31, 2018, 07:37:13 PM »
Hi Alexey Here is a snapshot of side view.  I'm not sure where you find valid matching points? Is this under workspace? It shows 156/180 images aligned with 303,000 points.

Darryl


z-air

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Re: swath mapping system - Zero resolution?
« Reply #3 on: May 31, 2018, 07:40:18 PM »
Another screenshot with boundary box.

Alexey Pasumansky

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Re: swath mapping system - Zero resolution?
« Reply #4 on: May 31, 2018, 07:59:22 PM »
Hello Darryl,

I assume that there could be something wrong with the calibration parameters estimation and focal length in particular.

Is there any possibility to send the project file (in PSZ format) to us? Via PM or to support@agisoft.com. Orthomosaic and DEM are not required - just alignment results.
Best regards,
Alexey Pasumansky,
Agisoft LLC

z-air

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Re: swath mapping system - Zero resolution?
« Reply #5 on: June 01, 2018, 08:06:37 AM »
Okay I've sent in requested info. 

Interestingly when I run the data without any exif lat/long/altitude info it will process the data in a dense cloud.

Alexey Pasumansky

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Re: swath mapping system - Zero resolution?
« Reply #6 on: June 01, 2018, 06:39:48 PM »
Hello Darryl,

Due to the method of the image acquisition, there are many cameras with identical coordinate information. I suggest to leave only one camera per GPS location enabled in the Reference pane.

Also it looks like the sensor pixel size is set incorrectly in the Camera Calibration dialog. Usually the sensor pixel size is about few microns, whereas in your project it is set to half a meter. I doubt that the camera with so large pixels has been used.

Additionally there are misaligned cameras in the project, it may be caused due to low forward overlap.
Best regards,
Alexey Pasumansky,
Agisoft LLC

z-air

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Re: swath mapping system - Zero resolution?
« Reply #7 on: June 05, 2018, 10:40:17 PM »
Thank you,

I have tried removing exif data and only leaving one image per location, still says zero resolution, also fixed the camera sensor/focal parameters, didn't solve this.  If I used Roll data would this help with alignment?