New Apertus Video: Open Land

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New Apertus Video: Open Land

Postby Sebastian » Sun Jun 26, 2011 6:08 pm

Background: When I visited Elphel Inc. in spring 2010 we went on a 3 day trip to the south Utah Canyonlands. A desert area that is famous for it's red rock colors and stone/rock structures.
Together with Oleg I filmed around 23 GB worth of Elphel video footage there.

After a long time I am eventually finishing the conversion and editing process soon.

Just a few stills for now:

Image
Image
Image
Image

Video will follow soon.
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Re: Upcoming New Video: In the Desert

Postby Nathan » Sun Jun 26, 2011 6:22 pm

Sebastian, these shots look beautiful! Very much looking forward to seeing the video! Nice stuff!
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Re: Upcoming New Video: In the Desert

Postby Sebastian » Sun Jun 26, 2011 6:30 pm

Thanks!

Though I also did learn a few things through this, like binning is something that should really not be used at all ;)

I shot everything with 2x2 binning in 720p to get the widest possible angle with the lenses we had available. When reviewing the footage after the trip I realised there are sub-sampling artefacts all over the image. What a disaster... So I am releasing all stills and videos only at 50% of the intended resolution: 640x360 pixels so you can't see any flaws ;)

I then removed all binning options in Elphelvision....


Another funny story:

Around one week after we shot in this valley Disney rolled in with their trucks to shoot "John Carter (from Mars)" http://www.imdb.com/title/tt0401729/ at pretty much the very same spot. I guess the red rocks make it a natural Mars location. Though we got all the good weather and I heard that it started to get really dry and hot just a week after we left, not convenient for shooting anymore... though I guess closer to Mars climate.... :D
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Re: Upcoming New Video: In the Desert

Postby Sebastian » Mon Sep 05, 2011 4:04 pm

Video is finished!

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Re: Upcoming New Video: In the Desert

Postby shijan » Mon Sep 05, 2011 5:39 pm

congratulations! very interesting picture with mixed parameters - from one side it looks very natural and filmic, and from another side it looks like very digital because low dynamic range of sensor.
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Re: Upcoming New Video: In the Desert

Postby Biel Bestué » Mon Sep 05, 2011 10:20 pm

this is snow in the desert? or is it salt?

nice the look seems similar the the one from the hvx-200, I bet it has a little bit more of latitude than the hvx-200, at least color-wise it will have more dynamic range.

do the uncompressed footage display posteritzation of any kind in the low-variation gradients?

the color aberration in the steep mountain in the third shot is definitely from the lens croping isn't it? Ii've seen this kind of color aberration in others images at elphel, I guess the chip is too small for such a big lens so it display those errors. isn't it?
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Re: Upcoming New Video: In the Desert

Postby Sebastian » Mon Sep 12, 2011 11:28 am

Biel Bestué wrote:this is snow in the desert? or is it salt?

nice the look seems similar the the one from the hvx-200, I bet it has a little bit more of latitude than the hvx-200, at least color-wise it will have more dynamic range.

do the uncompressed footage display posteritzation of any kind in the low-variation gradients?

the color aberration in the steep mountain in the third shot is definitely from the lens croping isn't it? Ii've seen this kind of color aberration in others images at elphel, I guess the chip is too small for such a big lens so it display those errors. isn't it?


It's snow.

We use JP4(6) as compression, there is no uncompressed option.

Could you post a screenshot of the croping/color aberrations you mentioned?
That would allow us to discuss it much easier.
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Re: New Apertus Video: Open Land

Postby Biel Bestué » Tue Sep 13, 2011 11:44 am

this kinds of color aberrations: http://wiki.elphel.com/images/7/77/Prot ... etail.jpeg

seem the kind of aberration that happens in that pointy mountain at the right of the 3rd shot on one side there is an bluish outline and on the other side a yellowish outline, this aberration seems more profund since this contrast situation happens on the side of the shot and not on the centre. amybe this is due a low quality lens?

the same happens in the trunk of the tree on the left also in the 3rd shot, the outmost part has a bluish outline, while the part more closer to the centre has a yellowish outline, now the video is quite low-res but still this aberrations can be seen.

it seems like blue is zoomed out a little bit out of the other colors, let me try to test this with blender and RGB separation.
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Re: New Apertus Video: Open Land

Postby Sebastian » Tue Sep 13, 2011 12:07 pm

Sounds like a classic chromatic aberration that you describe: http://en.wikipedia.org/wiki/Chromatic_aberration
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Re: New Apertus Video: Open Land

Postby Biel Bestué » Tue Sep 13, 2011 12:10 pm

Color
Image
BW
Image
R
Image
G
Image
B
Image

you can see the problem within the webnav R grows out while B grows in

it seems the typical chromatic aberration from the lens, I don't think that comes form debayering because the video isn't at it's full res isn't it? so debayering artifacts on a low res video are quite unlikely.

is this aberration simply due to low quality lens, or is it enhanced by the crooping?
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