HDR skydome exposure from Peter Guthrie on Vimeo.
For the 7 shots used to make this HDR skydome I used a Canon 1ds mk3 which has superb auto bracketing abilities as well as being very fast and having 21 megapixels. The lens used for these shots was a sigma 8mm fisheye which gives a complete circular image on a full frame dslr. I set the AEB to 7 shots 2 stops apart, which gave exposure times of 0.5s, 1/8, 1/30, 1/125, 1/500, 1/2000 & 1/8000 all at F20. This range of exposures is crucial for capturing the full dynamic range of the sun, which will eventually mean you get good strong shadows when you use the HDR image to light a 3d scene.
- Process raw files to remove chromatic aberration & to ensure white balance is consistent. I do this in Adobe Lightroom (pictured below), where you can copy the develop settings from the first file, and then batch process the remaining ones to save time.
- Export as 16 bit TIFFs
- Load TIFFs into Photomatix or Photoshop to blend into a single HDR, I use Photomatix as it seems to do a better job of removing ghosting artifacts (from moving clouds).
- Load HDR image file into Hugin. Choose lens type as fisheye when importing, and set the Horizontal field of view to 285 degrees (I arrived at this mostly through trial and error!)
- Hugin will complain that more than 1 image is required - ignore.
- Set pitch of image to 90, and adjust yaw so that sun is centred. If you know where the sun is, it helps later on when you come to rotating the skydome in your 3d application.
- in the stitcher tab, I take off soft blending as there is only 1 image, and press the ‘calculate optimal size’ button. Then hit ‘Stitch Now!’ (saving as a tif)
- Open 32bit tif in photoshop, clone out anything you dont want (dust in my case), save as 32 bit exr. Image below shows how the HDR should look when you drag the exposure slider in photoshop.
(click image for high res version on flickr)
Sometime, I’ll follow this up with something about how I use these in 3dsmax & Vray!
Very insightful… been wondering how to get this done easy for a while. i need one of those fish eye lenses to complement my old canon 5d.
Very inspiring. Would my Nikon D80 be a good candidate for HDRi creation?
Thanks for the great tutorial Peter! I’ve dugg this on CGDigg:
http://www.cgdigg.com/story.php?title=hdr-skydome-tutorial-by–peter-guthrie
CGDigg.com - Digg, for CG related info, vote on your favourite story or submit info you’ve found.
Thanks Chen
Daniel, for interiors and nice still days then a D80 would be as good as any. The tricky thing is being able to fire off enough shots quickly enough so that moving objects (eg clouds) blend nicely together on the HDR image. Thats why this particular combination, of a 1dsmk3 and a sigma 8mm fisheye, work so well. With one press of the shutter release you get 7 21mp images within about 1 second, and no need to stitch anything together.
Using a non fisheye lens has its benefits though: even higher resolution final images.
Hi Peter,
thanks for this tutorial !
But how did you manage to shoot all 7 images with one press.
In the 1DS mk3 manual it says the AEB is only a row of 3 images.
I ask this as i have a EOS 5D mk2 and there it is the same, i only get 3 images in a row.
is there anything special to setup ?
cheers
Michael
Thanks for your comment Michael, with the 1DS mk3 you can set it to take a burst of 3, 5 or 7 images in the custom function menu. Unfortunately there is no such option with the 5D mk2, otherwise I would have upgraded from my 5D mk1 by now!
thanks peter for the info.
this is really too bad…
maybe canon updates the firmware for this to be possible.
Well Canon just released a firmware upgrade to allow manual exposure in the movie mode of the mkII, but I still doubt they will change the bracketing options… hope i’m wrong!