Thanks, Stephen and Nicholas for the information on cubical projection. Frankly, I'm partial to spheres... I've always found them better as background environments -- cubes never seem right, the edges tend to be apparent. especially because this is a scene in a 360 space and i don't want to have to avoid the camera looking at the edges of the cube. But I also don't want to have to avoid the poles of a sphere. But I've never tried the cubical projection in Softimage, is it better somehow? You're right, Nicholas, it would be easier to paint out the distortion in PS. But I don't want to do all that work on creating a cubical projection and have it not read well in the render.
Have you used it effectively when you need 360 degree correctness? Thanks! On Jul 29, 2013, at 4:39 PM, Stephen Davidson <[email protected]> wrote: > Exactly. Then use the cross version (Pano2VR creates a horizontal cross) > setting Softimage's environmental mapping to horizontal cross. > Is this not working for you, now? > > > On Mon, Jul 29, 2013 at 2:54 PM, Nicholas Breslow <[email protected]> > wrote: >> The basic workflow I’ve used for this in the past is to convert the >> equirectangular panorama to a cubical projection. Then you can paint out the >> nadir (poles) on the top/bottom of the cube in PS/other to get rid of the >> distortion. You can use Pano2vr http://gardengnomesoftware.com/pano2vr.php >> for the conversion. After convert it back to equirectangular. Very similar >> to the Polar method mentioned before. >> >> >> >> Hope that is what you were going for – just glanced and thought I would >> share this. >> >> >> >> Nicholas Breslow >> >> >> >> >> >> From: [email protected] >> [mailto:[email protected]] On Behalf Of Nancy Jacobs >> Sent: Sunday, July 28, 2013 6:25 PM >> To: [email protected] >> Subject: Re: Environment sphere issues >> >> >> >> Thanks for this info, Stephen, but I really need the spherical environment >> for a seamless space experience. >> >> >> >> Now that I've got the implicit projection working, it does a better job >> rendering the image at the poles, but still not good enough. Guess ill have >> to drag a sphere into Mari and try painting out the distortion. That plugin >> you linked me to gives some cool vortex effects at the poles, maybe ill find >> a use for that! But I still wonder why it's working for your images and not >> mine. Maybe it's in the type of image and what is happening visually near >> the bottom and top of the image. >> >> >> >> >> On Jul 28, 2013, at 1:19 AM, Stephen Davidson <[email protected]> wrote: >> >> Here is a nice article on creating cubic environment maps from stitched >> panoramic photos, using Blender. >> >> very clever: >> >> http://www.aerotwist.com/tutorials/create-your-own-environment-maps/ >> >> >> >> On Sat, Jul 27, 2013 at 9:42 PM, Nancy Jacobs <[email protected]> wrote: >> >> Stephen, this plugin really didn't work for me. It way overdid some kind of >> smearing, spiraling algorithm. Looks a lot worse than the original. I wonder >> what he's thinking, or what went wrong here... Any ideas? >> >> >> >> Thanks for the link, however. I was really stoked when I thought it was >> going to solve this problem. Maybe something in Softimage mapping is trying >> to solve this and doesn't quite do it, so this plugin overcompensates? >> >> >> >> I still think implicit mapping would help, as the help files indicate, if I >> could get any image to show up on the sphere. >> >> >> >> Thanks again, >> >> Nancy >> >> >> On Jul 27, 2013, at 8:18 PM, Stephen Davidson <[email protected]> wrote: >> >> If you have Photoshop, here is a link to something called spherical mapping >> corrector: >> >> http://www.richardrosenman.com/software/downloads/ >> >> >> >> No 64 bit support, I believe. >> >> >> >> here is the install and use docs: >> >> Spherical Mapping Corrector - v1.4, © 2008 Richard Rosenman Advertising & >> Design. Release date: 03/15/03, Updated 09/28/08. >> >> >> >> >> >> INSTALLATION: >> >> >> >> Simply unzip "spheremap.zip" and copy "spheremap.8bf" to your >> "\Photoshop\Plug-Ins\" folder, or whichever plugin folder your host program >> uses. Load your program, open an image, go to the plugins menu and select >> the plugin. >> >> >> >> >> >> DESCRIPTION: >> >> >> >> This filter produces texture map correction for spherical mapping. >> >> >> >> When projecting a rectangular texture onto a sphere using traditional >> spherical mapping coordinates, distortion ('pinching') occurs at the poles >> where the texture must come to a point. Given the different topology of a >> plane and a sphere, it is impossible to avoid this, or any kind of >> distortion. However, by properly distorting the texture map, it is possible >> to minimize and even compensate for the polar distortion. >> >> >> >> Special thanks to Paul Bourke for allowing his algorithm to be ported to >> this plugin. For more information, please visit Mr. Bourke's site at >> http://astronomy.swin.edu.au/~pbourke/. >> >> >> >> Sub-Sampling: Specifies what type of pixel sub-sampling to use. (Nearest >> Neighbor being fastest, Bicubic being best. >> >> >> >> On Sat, Jul 27, 2013 at 6:46 PM, Nancy Jacobs <[email protected]> wrote: >> >> Greetings, >> >> I'm using the old-style environment spheres with an HDR image wrapped to >> light the scene, but invisible to rendering, and a beauty image visible to >> the render. The problem is the very visible distortion near the poles of the >> sphere. I need 360 degree visual acceptability. I am using a background >> which I've made seamless in both directions, a 2:1 rectangle. It seems this >> worked in renders at one point years ago in another software. Perhaps even >> XSI....I don't recall. >> >> I'm also trying to substitute this arrangement by using both an environment >> (using the HDRI), and 'Spherical Mapping' (using the beauty image), in the >> Pass Shaders. But I'm getting very strange results, so not sure if this is >> the way to go. Also, it's difficult to line them up properly so that the >> light in the HDRI is coming from the same place as the equivalent visible >> areas in the beauty image -- which of course one can do easily in the >> wrapped spheres. But in the pass shaders, they don't seem to use the same >> rotation systems... >> >> Any advice on getting an undistorted, seamless image going here? With proper >> orientations? >> >> Thanks, >> Nancy >> >> >> >> >> >> >> -- >> >> Best Regards, >> Stephen P. Davidson >> (954) 552-7956 >> [email protected] >> >> Any sufficiently advanced technology is indistinguishable from magic >> >> >> - Arthur C. Clarke >> >> >> >> >> >> >> >> >> -- >> >> Best Regards, >> Stephen P. Davidson >> (954) 552-7956 >> [email protected] >> >> Any sufficiently advanced technology is indistinguishable from magic >> >> >> - Arthur C. Clarke >> >> >> > > > > -- > > Best Regards, > Stephen P. Davidson > (954) 552-7956 > [email protected] > > Any sufficiently advanced technology is indistinguishable from magic > > > - Arthur C. Clarke > >
