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1. #Hdri looks dark brighter 3d software#
2. #Hdri looks dark brighter 3d iso#
3. #Hdri looks dark brighter 3d plus#

Everything was shot with the same Tungsten White Balance.

#Hdri looks dark brighter 3d iso#

Now the same color chart is slated with the plate and shot at F11 ISO 200 4 sec, i.e. A color chart is placed in the scene and taken along with the HDR pano. 10 EV, and should roughly be the "anchor" EV of the HDR pano. Say I have shot brackets at F11 ISO 200 1/4000 to 15 sec (HDR pano for 3D lighting), ensuring pixel values of light sources not clipped in the darkest bracket. Not trying to take away the artistic side of 3D lighting in VFX here. I am curious how can we push this eyeballing or "relative" approach, if I may, of calibrating HDR pano to a more systematic approach. Using gray ball and color chart has been bringing me far enough in terms of matching the exposure and white balance between HDR pano and plate/ground truth ref image. But what you want is the relation to how the plate was shot.

So initially there's only a relation to how you shot the pano.

Most likely the middle exposure will be used to determine the HDR's base exposure. But in real life I usually just peek at the camera operator's monitor, read off the white balance, and set my Nikon to the same.Īnd to the original question - the arbitrary part is the HDR merging process. There's two tutorials on that in the book (with Photoshop and the 32 Float Plugin, Nuke or Fusion will certainly do as well).

#Hdri looks dark brighter 3d plus#

For more accuracy I recommend shooting a bracket of color chart (like the Passport) with BOTH: the photo camera you take the panos with PLUS roll a reference clip with the plate camera.Īlmost more important is to match the white balance of the plate. I know that it sounds weird and arbitrary when you eyeball. Why do we have to grade the HDRI? If (as I understand it) an HDRI image is supposed to be a representation of the real world light values of a scene, then isn't grading the HDRI distorting these real world values? Shouldn't something like Photomatix spit out an HDRI that's ready to go for rendering purposes by default? Or am I doing something wrong here?

So I understand that we have to take our HDRI into something like Nuke and grade it using gain to roughly match it's base exposure to our backplate. but it often times doesn't - it's much too dark. I expect for the resulting render to look about the same in brightness as the backplates from my camera. I bring this HDRI into Maya and setup a VRay PhysicalCamera with the same F-number, Shutter, and ISO of the camera that took my backplates and hit render.

#Hdri looks dark brighter 3d software#

When I feed my bracketed exposures to an HDR merging software like Photomatix, it does it's thing and generates my HDRIs which I then stitch together for use in 360* IBL.