Page 1 of 3
My first "H"DRI Test
Posted: Fri Jun 24, 2005 4:32 pm
by Micha
Hi,
here my first test with a MXI sphere. The image is without any postwork. Tips: I have converted the HDRI per HDRShop as a dark LDR image (avoid a burn out in the lights) and in the MXI viewer I have set the intensity 360 and the Gamma 1. With neatimage it is possible to retouch the noise, but I want to show the raw image here.
the scene in Rhino
the "HDRI"

Posted: Fri Jun 24, 2005 4:39 pm
by Tyrone Marshall
Good test Micha!
Posted: Fri Jun 24, 2005 4:40 pm
by Eric Lagman
Very nice Micha. Looking forward to seeing more of these MXI images lighting a scene. I will have to try this out.........as soon as I get off work

Posted: Fri Jun 24, 2005 4:41 pm
by Mihai
Nice test, could you please also test it with a hemisphere (as low poly as possible) an as close as possible to the size of the "table" the dragon is sitting on? I mean make it only a bit bigger than that table.
Curious to see if that will help with the noise.
Posted: Fri Jun 24, 2005 4:51 pm
by philipbruton
great test, looks very real
Posted: Fri Jun 24, 2005 5:03 pm
by Micha
Thanks for the comments.
Mihai Iliuta wrote:Nice test, could you please also test it with a hemisphere (as low poly as possible) an as close as possible to the size of the "table" the dragon is sitting on? I mean make it only a bit bigger than that table.
Curious to see if that will help with the noise.
Halfsphere - good, I will try it in the next days. Today I test a rendering in double size in the same render time. I hope, I can denoise the image better without losing the details.
Small sphere - this is not so good, because the table show the near emitter surface more than the far emitter surface. The lighting on the table is not uniform and the scene looks like in a sphere with a backlighted photo (like this promotional backlighted images on the bus stop). Also I think, the DOF effect could be wrong. Best would be, if the sphere is approx. in the same size like in the real world. In my case it should be approx. 50 m ... 100 m.
Posted: Fri Jun 24, 2005 8:39 pm
by Micha
Hmm, I must do something other on my machine and so i must stop my double size speed test. But I'm very happy with the solution. Only one hour rendertime at double size - Filter "Remove Dust and scratch" in PS - one time denoiser - downscale to 50% and ready. The image is better than the 7 hour raw render image. Maybe, now it is a little bit like a biased renderer works, but it is fast.
Maybe, Maxwell will bring an option in the future to work like this, a little bit biased. So, the user could choose a fast not so perfect average solution or wait longer for an unbiased full quality. Please, don't hit me.
PS: I have choose a little bit stronger reflection on the black sphere. The sphere good shows the HDRI like effect.

Posted: Fri Jun 24, 2005 8:46 pm
by tom
yeah i also tested MXI this way and it works damn fast...
i liked it and your scenes also, great micha!
Posted: Fri Jun 24, 2005 8:51 pm
by Micha
Thank you, master Tom.

Posted: Fri Jun 24, 2005 9:06 pm
by deesee
Where is the best place to find out a bit more on this HDRI thing? I've seen the acronym before, but don't know what it is.
Thanks!

Posted: Fri Jun 24, 2005 9:17 pm
by Maximus3D
Nice looking HDRI tests with Maxwell, although something feels wrong but i can't quite point the finger at what it is yet.. :/
/ Max
Posted: Fri Jun 24, 2005 9:18 pm
by tom
deesee,
they mean:
HDRI: High Dynamic Range Image
Images having more than 8 bit-per-channel depth. (usually 16 and 32)
HDR, EXR.... (and now MXI)
LDRI: Low Dynamic Range Image
Images having 8 bit-per-channel depth. (usual images we all use)
BMP,TGA,JPG,TIF...
... HDR images are preferred for illumination purposes.
Posted: Fri Jun 24, 2005 9:24 pm
by deesee
Thanks guys!! I've got my weekend reading taken care of.
Posted: Fri Jun 24, 2005 9:39 pm
by deesee
One more question, sorry

...so an MXI is essentially another type of HDR image?? I'm remembering that LCD television thread here...that could essentially be reproduced by applying an MXI (assuming my first statement is correct) right?
Thanks
Posted: Fri Jun 24, 2005 9:50 pm
by Mihai
deesee wrote:so an MXI is essentially another type of HDR image??
quick, edit that part before the developers see it!
it is said an mxi is MUCH more than just a hdr format. Well actually I think it can be ONLY a hdr format, but it can also hold a lot more info about a scene rendered with Maxwell.
Currently there is no way to convert directly a "usual" hdr to mxi format. You have to first convert your hdr images to a ldr format such as bmp, then convert that to mxi with mxiviewer.
btw, this rescaling trick seems to work a lot better now with beta. I remember eldo made a test with beta, and also isma I think before with the alpha.