Messages

46

General / Re: Surveying trees: canopy comes out well--tree trunks are way off.

« on: June 01, 2016, 11:13:40 AM »

looks to me like you have used high field reconstruction which is not good for the type of work you are looking at since high field models are just nice if you are looking at them vertical or it is very flat
try arbitrary reconstruction or even better use only the point cloud
frank

47

General / Re: Projection inconsistency

« on: May 03, 2016, 10:39:10 AM »

hi
you dont need to mask the water
you will see that the results are much better with ground control
however the shape of the object (shoreline) will still get you problems try to make the coridors not to long and increase with a bit which should get you better results. i would recomend to have at least one flightline completly over land
or have U L or T schaped flight paths with "excursions" inland of course providing ground control there so you can solidify the models poition in space a bit better and make sure they are not tilted paralel to the shoreline
frank
p.s. could you provide a sample unedited image of the inspire camera with costline ?

48

General / Re: Getting small distorted/blurry areas on scan and question about depth filtering.

« on: April 28, 2016, 05:40:27 PM »

this sometimes hapens with stuf from the back or foreground of the focus point being used for texturing you can fight this by agressive masking and trying to get as much stuf in focus as posible (depth of field, apperature)
frank

49

Bug Reports / Re: Problems reconstructing simple object

« on: April 28, 2016, 10:46:09 AM »

as said before you need something for photoscan to hold on to
use milimetric paper with soem random sribls on it or a non refective newspaper page instead of the a4
the newspaper will be modeled as well but you can cut it of
frank

50

General / Re: Projection inconsistency

« on: April 28, 2016, 10:41:26 AM »

looks like an allignment problem
1 its a very long narow band = bad for photogrammetry
2 it is involving water and lots of it on one side of the images its always water = bad for photogrammetry
3 camera being a very wide angle fisheye type = bad for photogrammetry and usualy results in the model shape you see if not corrected
4 on bord GPS = not realy precise enough to make god for the bad factors above
5 lack of ground control = being the main problem here since the factors above are very adverse and thats the least you can do to help photoscan do its work :-)
best regards
frank

51

General / Re: Image overlap

« on: April 25, 2016, 06:07:13 PM »

hi
you can of course also work in the point cloud and use the gradual selection and then image count to get an idea of where the overlap is low and where it is high
frank

52

General / Re: Photoscan Model accuracy

« on: April 25, 2016, 06:04:01 PM »

hi
well there are the error values in the control tab but they are of course only of limmeted use to understand the models accuracy since they are not representative of the final result and in most cases not independend
i have developed my own routine to create decent statistics on the accuracy
since iam in most cases interested in vertical accuray this is simple and can be done mostly automated
i use the DEM and an additional dataset of ground check points the more the better. Then i run a coparison of booth values in QGIS and can have the result as a graph or a table including standard deviation and 2xSD as well as all other kind of data i like
my last big model had 31000 check points and with this data you can do some serious statistics
frank

53

Feature Requests / Re: Please make batch processing display time spent per step

« on: April 20, 2016, 12:05:18 AM »

+1

54

General / Re: Order of Photos drastically affects reconstruction

« on: March 11, 2016, 12:26:34 PM »

did you use generec as pair preselection, if yes then the order how you take photographs is very important if you use disabled then it should have no influence
frank

55

General / Re: Interpreting the DEM

« on: March 11, 2016, 12:22:32 PM »

on the eges of the model you usualy have non vailid data make sure to scan a larger area and then crop to an extend where you still have enough overlayand not just the forward looking stereo image
frank

56

General / Re: High resolution snapshots

« on: March 11, 2016, 12:20:55 PM »

+1 especialy in anaglyph

57

General / Re: After align photo my photo look like below picture...how I can resolve that?

« on: March 08, 2016, 12:51:44 PM »

hi
it seems that the alignment was only succesful for the first few images
have you tried different allignment settings. have yu got enough overlap?
frank

58

General / Re: Appropriate time to add GCP?

« on: February 18, 2016, 04:13:26 PM »

hi
first align and reference your image set using GPS data or maybe 4 gcp in the corners
then load a list of coordinates for your gcp with the impsrt function
then select one marker after the other and use right click images by marker and only images which contain the extimated marker position are shown and also a blue flag should show aprox where the point is then move the flag to the correct point next image and so forth
frank

59

General / Re: Merging chunks

« on: January 27, 2016, 10:46:44 AM »

if you have two seperate clouds created seperatly by GPS (i presume onboard uav gps) then each cloud will have the individual errors of the gps data and can therefore not be allignet by gps data alone
use ground control markers to align or just process the images together which usualy gives the best results since it workes grat for steep slopes since the angle of light rays intersecting can be improved by combining nadir and oblique photography this will result in better depth maps and better point cloud.
make sure to set the accuracy parameters for your gps right!
frank

60

General / Re: DNG, tiff, and Jpeg. Processing dilemma looking for advice/discussion

« on: January 27, 2016, 10:43:01 AM »

dng support would be great indeed!
frank