Very Cheap HDRI DIY
This Tutorial is to show you how to use the inexpensive thing to make the cool job. This is my first HDRI-Tutorial, I hope it will help you. Sure, the technique explained in this tutorial is somewhat inexact, that's because we use a very simple and cheap way to reach the effect we are going for. However, this tutorial can also how HDRI works in general.
HDRI is currently the thing all of CG is talking about. HDRI is the abreviation for "High-Dynamic Range Image". It allows you to create realistic lighting for your scenes. We all know the world the way we see it through our own eyes. Through the 256x256x256 steps of the RGB-colour setup we lose alot of colour-detail - now we can use HDRI to intensify the impression of reality in CG-scenes. Now, follow me through this article and learn how I use HDRI the cheap way. Also I
will communicate some principle information on HDRI to you, so bear with me and
Some things you need:
1. HDR Shop.exe
2. lightgen_plugin.exe (HDR Shop Plugin)
And, if you like to take a look at the resources and test-scenes I used, you can get them here:
Very Cheap HDRI DIY. Resource Download. Very Cheap HDRI Render test Scenes files.
A couple of more things you need:
A digital camera, cheap or expensive, doesn't matter A mirroring metal ball, I useed a chinese hand-sport ball (Qui-Gong), you can find those at: www.bigbook.com www.amazon.com
Also you need a stand for the ball, eg. the stick of a CD-R 100-pack is what I use here
Now find the some place you like, I used my work place's table.
Now, put up camera and metal ball as on the image below. Make sure lens and ball are on one level! I made that particular mistake many times, it messes up the reulsting reflections, when camera and mirror ball are not on the same level.
Take 7 pictures from each positon (A and B on the image above); use different exposure times, if possible. If you (like me) don't own a camera that allows for this, it's ok to use "Exp.+/-" to achieve different exposure times, that's not so exact, but it will do to make your HDRI - so just do it !
Next we need to open the HDR-Shop (download above)
Select Create > Assemble HDR from Image Sequence. Loading the images we took, use the calculate button (ignore the error infomation). Then save the generated image. (Little Tip: If you find the generated image too dark you can change the exposure steps using View > Exposure > Stop up + to adjust the images and use the Pixels > Scale to Current Exposure to lock that steps light image, this tip can help you to easily get the you want)
Another little tip: you can use the ACDSee software to check the images detail:
Ok, we have the DIY's HDRI put together, now you want to make the panoramic image. You can find detailed tutorials on this on the official
site of HDR Shop.
After merging the two angled HDRI, we get the panoramic HDRI. Now we can do the lighting job. We need to open the HDRI maps as enviroment texture maps. Refer to this tutorial to learn how to set up MEL files with the Lightgen-plugin.
Now we finish our very cheap HDRI Render, by utilizing the good lighting tools "Lightgen".
Check out the linked site below, you can download HDR-Shop there, it is a good place to find more HDRI-Tutorials as well.
Paul Debevec Home Page http://www.debevec.org/http://www.debevec.org/HDRShop/
Paul Debevec, for his research on HDRI, and to let me know about all of this.
All HDR-SHOP software researchers, your make cool and useful tools.
HdrShopLightControl Maya HDRI lighting Plugin-Designers.