HDRI Manipulation (scaling)

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PDRA
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Joined: Fri Sep 27, 2019 8:49 pm

HDRI Manipulation (scaling)

Post by PDRA » Mon Jan 13, 2020 12:47 am

Hi there again!

I was wondering this time if there is a way to manipulate the HDRI I'm using.

Particularly, what I would like to do is to scale it to adjust the reflection of the object. Is there any way to do it? I know that i can adjust the rotation but I don't see it for the scale.

There is a message that says "For free transformation use a hemi lamp" but, if I'm not wrong, they removed it in the latest releases.

I've tried doing it with a sphere but it isn't working.

Regards, saludos
Pablo

Fox
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Re: HDRI Manipulation (scaling)

Post by Fox » Mon Jan 13, 2020 5:53 am

The scale won't change reflection size, i don't think there is option for it.

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B.Y.O.B.
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Re: HDRI Manipulation (scaling)

Post by B.Y.O.B. » Mon Jan 13, 2020 10:29 am

PDRA wrote:
Mon Jan 13, 2020 12:47 am
There is a message that says "For free transformation use a hemi lamp" but, if I'm not wrong, they removed it in the latest releases.
This was moved to the sun light, this description should be updated.

What you ask for is not really possible: The HDRI is mapped to fit on a sphere surrounding the scene at infinite distance. Scaling the whole thing would not change the look at all. Scaling just one region would distort everything else, something like this:

Image

PDRA
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Re: HDRI Manipulation (scaling)

Post by PDRA » Mon Jan 13, 2020 2:49 pm

Hi,
I upload a video to better explain what I would like to achieve.

I'm trying to find if there is a way to fine tune the HDRI like with the tools that Keyshot offers.

Regards, saludos
Pablo
Attachments
HDRI adjustment example2.mp4
(3.05 MiB) Downloaded 16 times

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Dade
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Re: HDRI Manipulation (scaling)

Post by Dade » Mon Jan 13, 2020 5:00 pm

I'm trying to understand what it is: it looks like some kind of field view angle that work only for HDR (a bit strange).
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kintuX
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Re: HDRI Manipulation (scaling)

Post by kintuX » Mon Jan 13, 2020 6:27 pm

PDRA wrote:
Mon Jan 13, 2020 12:47 am
Hi there again!

I was wondering this time if there is a way to manipulate the HDRI I'm using.

Particularly, what I would like to do is to scale it to adjust the reflection of the object. Is there any way to do it? I know that i can adjust the rotation but I don't see it for the scale.

There is a message that says "For free transformation use a hemi lamp" but, if I'm not wrong, they removed it in the latest releases.

I've tried doing it with a sphere but it isn't working.

Regards, saludos
Pablo
You can apply HDRI tex to the sphere (making it an emitter) with UV spherical mapping. Then manipulate sphere scale/rot/pos to your liking.
Here's a simple scene to check
IBL_HDRI_mnpl.jpg
Attachments
IBL_HDRI_mnpl.blend
(98.07 KiB) Downloaded 7 times

PDRA
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Re: HDRI Manipulation (scaling)

Post by PDRA » Mon Jan 13, 2020 7:31 pm

You can apply HDRI tex to the sphere (making it an emitter) with UV spherical mapping. Then manipulate sphere scale/rot/pos to your liking.
Here's a simple scene to check
Thanks kintuX! That is what I've tried with the sphere but I couldn't solve two things:
- It looked very "dull" when I applied it in comparison to the result I got using the HDRI slot in the world tab (even after playing a bit with the gamma and brightness) I might solve this one fine tunning it a bit more.
- The second thing I couldn't work out is how to make the sphere not appear in the camera but only in the reflections (also avoid self casting shadows). This is mainly to get a correct Alpha channel to later use for the composition. As I remember this feature will be released in the next version, right? Or is there a way to do it with the current one?
I'm trying to understand what it is: it looks like some kind of field view angle that work only for HDR (a bit strange).
It is working as kintuX showed. It seems to be projected over a sphere that you can control its size, Z position and rotation. You can see in the very first seconds when it gets really small that it has the shape of a sphere.

Regards, saludos
Pablo

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