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WesM
05-23-2003, 07:07 AM
I want to learn how to make my own hdri images. I found some tutorials on the web, but they left me a little confused. Is there an application or a way to make hdri images on the mac. I know there is a program call HDRShop but it doesnt work on mac. I would greatly appreciate some advice or knowledge anyone can share.

Thanks,
Wes

Darttman
05-23-2003, 09:01 AM
I was just reading a good tutorial on HDRI rendering in LW's online tutorial area so do a search for it. It will answer all of your questions large and small

WesM
05-23-2003, 10:16 AM
Thanks for reminding me about the Modeling and HDRI Lighting a Gamepad tutorial on Newteks site. I read that one a while back and it explains alot. I will check it out again.

I think were I have the most trouble understanding, is making an HDRI image. I understand the exposure part, but I need some software that will compile the shots into one. I cant seem to find a way to do it on a mac. I found out 2 programs that could do it, HDRshop and mkhdr. They dont run on a mac though. I also found a tutorial where some people produced good results with regular images.

Thanks,

Wes

claw
05-24-2003, 05:02 AM
Its not a app for Mac that can compile a HDRI-image from 24bits images at the moment.

However you can make "virtual" HDRI images with Lightwaves 128bits rendering-engine.

Beamtracer
05-24-2003, 08:02 PM
Most of the compositing applications on the Mac (with the exception of After Effects) can handle, paint and manipulate 32bpc HDRI images. Examples are Shake, Combustion and Commotion.

However, I expect you were probably looking for something cheaper than these alternatives.:)

claw
05-25-2003, 03:26 AM
Hmm, I have been doing some test yesterday. Iam just a newbie on the HDRI thing so maybe I got something wrong. However, I managed to make a hdri image from a 24bit image. All I did was that I first re-saved the 24bit tga to a 96bit hdr-file in side Lightwave. Then I loaded the hdr file to LW's image-editor and started to play with the hdri-exposer tool. If you drag the white point and the black point you can easily increase the brightness to over 300% of that image, that is not possible with only 24bit files.

I don't know if this is the right way to make a HDRI, maybe its a little to easy:)

WesM
05-27-2003, 09:42 AM
Hey everyone, thanks for the info!

That's interesting, making HDRI images from lightwave. I am going to give that a try. So I just need to save the file in an HDRI format at a high bit depth, then bring it back into lightwave and mess with the brightness controls in image editor?

I have been using AfterEffects for all my compositing, but I am going to step up to combustion. I really wish I could use Shake. I saw shake at NAB this year. It is awesome.


Thanks,
Wes

Arnie Cachelin
05-27-2003, 10:07 AM
The talented and generous Kenneth Wooduff got the unix mkhdr utility running under OSX. I think you might find it at kennethwoodruff.com. More difficult than the processing of the exposures is actually taking them. You should find a scene and camera that are absolutely still for the time it takes to make 5-8 exposures, and probably you should find a way to change the camera settings without disturbing the camera. If you use digital, you must save in an uncompressed format, since jpeg artifacts will change the different exposures differently. If you shoot on film, then the processing must not be tweaked, which is not usually the case. Paul Debevec had to get a custom, un-adjusted photo CD developed, as I recall.

WesM
05-27-2003, 10:41 AM
Hey Arnie,

That is great!!! I checked out Kenneth's site, but I did not see anything about mkhdr. I emailed him about it.

Thanks a lot,

Wes

Beamtracer
05-27-2003, 06:58 PM
It's good to see the world authority on HDRI, Luxology's Arnie Cachelin still reads this forum!

Originally posted by Arnie Cachelin
More difficult than the processing of the exposures is actually taking them. You should find a scene and camera that are absolutely still for the time it takes to make 5-8 exposures
The German company Sachform has recently started selling a collection of HDR images on their website. Interesting that there are ocean scenes, so I don't know how they managed to work with the movement of the waves.
http://www.sachform.de/

If you are looking for Kenneth Woodruff's MKHDR software, you can find still find it on his website. BEWARE: This is beta software, and it will start downloading immediately when you click on the link below. Filesize about 260k.
http://www.kennethwoodruff.com/digitalart/files/mkhdr_OSX_beta2.sit

js33
05-27-2003, 10:05 PM
Originally posted by Beamtracer
It's good to see the world authority on HDRI, Luxology's Arnie Cachelin still reads this forum!


Arnie went to Luxology as well. :( Man is there anybody still working on LW? I mean 8 as 7.5c still has all the usual names on it.

Cheers,
JS

Beamtracer
05-27-2003, 10:19 PM
Originally posted by js33
8 as 7.5c still has all the usual names on it.

You mean you're beta testing Lightwave 8?!?!?

wizlon
05-28-2003, 02:03 AM
Here we go again....

WesM
05-28-2003, 06:49 AM
Thanks for the links Beamtracer!

I downloaded MKHDR. Hopefully I will be able to figure out the install. I'm not to savy with the terminal.

Wes

claw
05-28-2003, 08:23 AM
just drop the MKHDR file into the Terminal window and press enter.

WesM
05-28-2003, 08:28 AM
Just as I thought, I can't figure out how to run the app. :(

I am not good with all of the terminal stuff. I'm not sure if this needs to be installed or if it just runs from the terminal. When I try to make the file, terminal says, "nothing to be done to file." I went to the debevec site, where the online docs are, and It mentions that the app runs from the shell. I tried to open the mkhdr from the shell and I get this error, "2003-05-28 10:19:58.660 open[845] LSOpenFromURLSpec() returned -10814 for application (null) path /Users/wesm/bin/mkhdr." If anyone could shed some light on this, I would greatly appreciate it. This whole hdri thing is killing me. I may just have to give it up.

Thanks,

Wes

WesM
05-28-2003, 08:35 AM
Hey Claw,

Thanks for the tip. It worked with no problem!!!

Wes

riki
06-01-2003, 08:17 PM
Here's a tut on 'REALISTIC LIGHTING WITH LDRI IMAGES (FAKING HDRI)'

http://www.3dluvr.com/intercepto/maya/tutorials/ldri_lighting/ldri_light.htm

also this looks interesting from ILM

http://www.openexr.com/

claw
06-02-2003, 04:15 AM
Thanks Riki!