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Author Topic: Blurry Patches in Orthophotos  (Read 4940 times)

Ashura

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Blurry Patches in Orthophotos
« on: July 21, 2015, 08:37:41 PM »
Hi all,

so I am getting blurry patches in my orthophotos and am not sure why. I though maybe it was due to photos with high/low pitch and roll values- but I disabled those cameras and reprocessed with similar blurry results.

I am pretty sure all my photos are sharp (hard to inspect 4000 photos). Just wondering if there is something else I can do that may help with this issue. Perhaps I am missing something- any help is greatly appreciated. Thanks!

Alex

Marcel

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Re: Blurry Patches in Orthophotos
« Reply #1 on: July 22, 2015, 10:14:09 AM »
Did you check some source images that are pointing directly at a blurry patch? The blurry patches seem to have some ISO noise still, so I think the photos itself are blurry.


We just released a free Windows utility to check visually sharpness on a large number of photos (although 4000 photos would be a stretch):

http://www.agisoft.com/forum/index.php?topic=4070.0

James

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Re: Blurry Patches in Orthophotos
« Reply #2 on: July 22, 2015, 10:35:02 AM »
Right click on the mesh where the texture is blurry and select 'Filter photos by point' to see only images covering this patch in the photos pane.

Then select only the 'enabled' photos in the photos pane and right click on them and select 'Filter photos by selection' to only look at photos that may be responsible for the blurry texture.

Optionally (if using pro) right click the middle of the blurry patch and select 'create marker', then highlight this marker in the reference pane.

Now open one of your photos in the photos pane and cycle through the filtered set using page up/page down. The view should always centre on the selected marker position if you created one.

Hopefully the culprit should now be easy to find!

If not, check Tools -> Mesh -> View Mesh UVs to see if the UV map was badly distorted in the blurry areas for some reason. Switch to scaling view to see any stretched areas.

Ashura

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Re: Blurry Patches in Orthophotos
« Reply #3 on: July 23, 2015, 06:47:54 AM »
Thanks Marcel and James, you have been extremely helpful.

I tried just manually checking the photos using James' method and it seems like a couple of the sensors picked up blurry images for Red and Green bands (using micasense).

I will also try out the software pixelkeeper which seems immensely helpful. I am going to eventually retry the mosaics when I have time and update the results. Gotta sort out something else now! haha