HDRI

[Jake]

HDRI

Here's the HDRI I used in the Fallingwater render, but at a much lower resolution. I've been trying to light building exclusively with HRDI's, but there is a lack of light on the bottom surfaces. What I have done, thanks to Tim's questioning why black, is use a lighter neutral gray along the bottom. of the HDR. This will give you the clouds and illumination from above and some fill light from below, depending on how you models is constructed.

If you are doing close-ups of certain areas that don't include the ground then turn off you ground so it isn't visible and this will allow the lighter portion of the HDRI to light the underside of the eaves etc. Play with the power too. It need to be turn up to 2, so that may burn out the sky image. In that case use the HDRI exclusively for lighting and render with colored background so that you can then strip in a sky later in photoshop. This gives you the best control.

Well I just tried to upload and it was too big. I thought Martin had bumped up the size for attachments. Send me an email until I figure this out and I'll send it along that way.

 

[Jake]

I sent it to Martin. Maybe he can post it somewhere here at the site.

 

[Martin]

Hi,
here is a link to Jeffs HDRI file.

http://www.cheetah3d.com/download/HDRI/sunnyAmbient.hdr.zip

Many thanks for offering the file to us Jeff.

By,
Martin

P.S. Has anybody ever tried to generate a HDRI with Terragen? I haven't tried it by myself but it looks like an reasonable solution to create full 360°x180° HDRI environment (sky and mountains) panoramas.

http://www.planetside.co.uk/terragen/
http://www.jomeder.com/plugins//highdynamic/
http://www.path.unimelb.edu.au/~bernardk/terragen/hdr/

 

[Jake]

I've toyed with Terragen a bit Martin. I could never get anything to nice out of it for some reason, but I didn't try REAL hard.

I think I'm going to get Vue 5 so I can get better landscape environments for my models. You can export Vue 5 skies out as HDRI's. I read that this afternoon. I downloaded the demo so I'll take a look at how well it works and let you know. I can create a series of general HDRI's if you want to host them Martin. I could do a couple night and a couple day versions.

Let me know.

 

[Martin]

Hi,
if the demo allows saving that would be fine. I will host them for you. No problem.

By,
Martin

 

[Jake]

Hi,
if the demo allows saving that would be fine. I will host them for you. No problem.

By,
Martin

No saving or files over 640x480. Pretty useless demo, but it's good for 60 days!

 

[Nilkimas]

one question, how do you make an HDRI out of the images (the Six frames of a scene), do you just have to put them to one image or what?, because i can make quite good landscapes with Terragen, but i don´t know how i would make an HDRI out of it.
So how put i the 6 different images, so that i get a working HDRI,
if i get it to work, i would share it to the Cheetah3D community!


regards,

 

[Nilkimas]

oh , see, your link links, to a site, how to create a HDRI,
-EDIT- but i see, on the third link, you need a plug-in/program which seems only running on windows, so how to put all 6 images together?

thanks,

i hope to release some HDRI's soon

 

[Jake]

Cubic Convertor. That's good on a mac.

 

[Nilkimas]

i don't can find it, i looked at Versiontracker and macupdate
could you post a link , please!

 

[Jake]

i don't can find it, i looked at Versiontracker and macupdate
could you post a link , please!

I spelled it wrong.

http://www.clickheredesign.com.au/cubicconverter/

 

[Martin]

Hi Jeff,
can cubic converter work with HDRI files?

In general it looks like that there are only very few Mac tools available which can edit HDRI files. Even GraphicConverter just loads HDR files but doesn't save them. And Photoshop CS 2 is quite expensive

By,
Martin

 

[Martin]

Hi,
I've just tried cubicconverter and I failed to load a HDRI file.

Does anybody else know a simple image processer where six hdri images could be copied together to a HDRI file in the cross format?

By,
Martin

 

[Jake]

Hi,
I've just tried cubicconverter and I failed to load a HDRI file.

Does anybody else know a simple image processer where six hdri images could be copied together to a HDRI file in the cross format?

By,
Martin

The only program I know of is HDR Shop, and it's windows only. That's why I fake it. A mac program for manipulating a hdri is not to be found–anywhere.

 

[peer]

Hi Jake, Martin,

In another HDRI thread I said I would try this aswell with Cubucconverter. And as Martin, I can't seem to load HDRs, too bad. Maybe if I ask my boss very kindly for a Photoshop update .

Regards,

Peter

 

[Jake]

Sorry Peter, I use Cubic converter to make the 360 panos, THEN I use PhotoshopCS2 to make the HDRI's. Cubic Convereter will not work with 32-bit images.

Like I said the HDRI's I use are kind of faked. The pixel depth is not as good as it should be. There just aren't enough mac based programs for working with HDRI's.

So export tif's from Terragen. Join in CubicConverter, import into PhotoshopCS2 and adjust the curves so you don't have any bright white or black black. double the height by adding black to grey to white, whatever the desired effect. A light bottom half will give you more fill light under the the eaves without adding extra lights. Problem is if you have a plane in place for ground then the effect will be diminished because the plane will block the light from below. In the fallingwater image I didn't have a ground plane so the light was good under the eaves. You can get away with that if you are doing little vignettes of the model. If you are viewing the entire model, then it's not always possible to get this effect because you need a ground plane.

Convert to 26-bit, then 32 bit, save as a Radiance file. Here is a simple openSky HDRI I made in photoshop in 1 minute. Doesn't hasve to be anything fancy. I'll also upload a jpeg version so you can see what it looks like.

 

[Jake]

Here's the jpeg.

 

[Jake]

This is how it lit the model. No other lights.

 

[Jake]

Now, in the prevoius image I hade a ground plane in the scene which blocked a little of the light form below. In this image I removed the gound plane. Look at the lighting under the eaves and inthe corners. Much better. This used the the same 126k bluesky HDR I made in PhotoshopCS2.

 

[Jacques]

Photomatix

Hi,

Not sure if this is old news.....

I have not tried this , but could this be an alternative to PhotoshopCS2 for creating HDRIs?

Photomatix
http://www.hdrsoft.com/index.html

Hope it helps. :wink: