Author Topic: Shadow bokeh effect?  (Read 1703 times)

2019-12-17, 19:43:50

bishbashross

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Not sure what to call this but is it possible to achieve this effect without workarounds? I'm guessing not.

Anyone have any experience of this. I'd imagine you'd have to fake it by creating a tree mask and blurring with something like lenscare, then using that to cast a shadow?

Interested to hear peoples thoughts. :)

2019-12-18, 03:18:25
Reply #1

burnin

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In principle,
the larger the Sun Size - the wider and more diffused the emissive source is, the softer and wider the shadow gets. Same occurs in relation between the shadow transmitter (ie. leaf) and its receiver (ie. ground) - the larger the distance between, the more diffused is the signal receiver gets. (see attached and pay attention while observing environment)
;)

2019-12-18, 11:17:44
Reply #2

GeorgeK

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From what I can see it's very dependent on scene settings, leaf geometry/shape, tree distance, Sun Azimuth etc. You can get pretty close tinkering for sometime.
“Every artist was first an amateur”

2019-12-18, 12:30:59
Reply #3

maru

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This thing definitely does happen in Corona if you set up your sun and tree as similar to reality as possible.

2019-12-18, 12:35:46
Reply #4

sebastian___

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The image Corona_GK posted does seem to show the circle effect, but not as pronounced as the circles you get in reality.
Now I'm curious myself if renderers can simulate that circle shape of the sun in the shadows.

2019-12-18, 14:12:25
Reply #5

maru

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2019-12-18, 15:58:39
Reply #6

bishbashross

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From what I can see it's very dependent on scene settings, leaf geometry/shape, tree distance, Sun Azimuth etc. You can get pretty close tinkering for sometime.

This is not bad! Still lacks the beauty and sharpness of the real effect to me though.

Maru, that looks like the DOF doing most of the work there I think. Image I posted is sharp throughout the frame.

2019-12-18, 20:55:37
Reply #7

romullus

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You don't need anything special to get this in Corona, just plant a tree and lit a sun. This phenomena depends on two things - right distance between the leafs and the ground and many small gaps between the leaves. Usually it's not hard to get it fulfilled. Basically, it's the same DOF, it just happens not in a lens, but between the leaves and a ground. Gaps between leaves acts as an aperture and ground is a film, or sensor.
I'm not Corona Team member. Everything i say, is my personal opinion only.
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2019-12-18, 22:12:11
Reply #8

mferster

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More examples!

You can even recreate the fun bokeh effects you see during solar eclipses by putting a sphere far enough away from your scene.
« Last Edit: 2019-12-18, 22:37:20 by mferster »

2019-12-19, 08:34:01
Reply #9

GeorgeK

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It's one of those things that someone made accidentally and an entire team of people try to reverse engineer!
“Every artist was first an amateur”

2019-12-19, 10:03:45
Reply #10

romullus

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You can even recreate the fun bokeh effects you see during solar eclipses by putting a sphere far enough away from your scene.

Wait a minute! So you actually added 3D sphere blocker between the sun and the scene? Whoa! I unsuccessfully tried to recreate this phenomena by painting a sun eclipse into HDRI map, but required resolution would be insane, so i dropped my attempt. It never crossed my mind that this can be achieved with 2D sun and 3D moon :] Super cool!
I'm not Corona Team member. Everything i say, is my personal opinion only.
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2019-12-19, 17:23:32
Reply #11

mferster

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Wait a minute! So you actually added 3D sphere blocker between the sun and the scene? Whoa! I unsuccessfully tried to recreate this phenomena by painting a sun eclipse into HDRI map, but required resolution would be insane, so i dropped my attempt. It never crossed my mind that this can be achieved with 2D sun and 3D moon :] Super cool!

Yah, that's exactly correct! You can even do goofy things like putting stencil shapes in front of the sun.

2019-12-19, 17:46:28
Reply #12

maru

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Maru, that looks like the DOF doing most of the work there I think. Image I posted is sharp throughout the frame.

There is no DOF in my scene whatsoever! :D Just download it and see.

2019-12-19, 19:28:34
Reply #13

GeorgeK

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Wait a minute! So you actually added 3D sphere blocker between the sun and the scene? Whoa! I unsuccessfully tried to recreate this phenomena by painting a sun eclipse into HDRI map, but required resolution would be insane, so i dropped my attempt. It never crossed my mind that this can be achieved with 2D sun and 3D moon :] Super cool!

Yah, that's exactly correct! You can even do goofy things like putting stencil shapes in front of the sun.

This is hilarious!
“Every artist was first an amateur”

2019-12-19, 19:47:56
Reply #14

burnin

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... and a new feature for Corona 6 - Sun Shape ;)