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HJ-panorama
09-09-2008, 02:05 PM
Hello


based on the documentation and tests, the filter in final gather tab in render settings is for smoothing the final gather points so they smoothly interpolated into each other...

but when I set the filter other than 0, for instance 1 or 2 the scene gets 90% black..

also it is semi blotchy, I did changed the min and Max radius to some reasonable amount based on my overall scene size... still i get some blotchy an noisy areas...

what should I do for these?


thank u in advance

lauras
09-09-2008, 05:35 PM
Hi!

The FG filter's purpose is to eliminate unnaturally dark and/or bright spots. It attempts to smooth out and average values of the FG point information. It should not yield drastic results like darkening your render to 90% black. Could you possibly post some images that show an FG filter value of "0" and an FG Filter value of "1" for comparison?

I would also make the suggestion that when you are test rendering that you do not change the values of more than 1 attribute or render setting at a time. This allows you to see exactly what each attribute is doing to your render.

L

HJ-panorama
09-10-2008, 12:37 PM
thank u lauras

I think your right! ....that is completely odd to have such this effect...

I 'm doing some other tests to see what happens... separately of course.. FG and GI and both etc...

cheers

Narann
09-12-2008, 09:34 AM
If you render your scene without any FG or IG, what do you have?

Good luck! :wavey:

Edit:
Could you give us your output?
Is there message about a photon that can't be projected?

berniebernie
09-12-2008, 11:33 AM
It's often overkill to use both GI and FG - and as mentioned filter just filters out extreme values, Point Density and Point Interpolation should be the ones you play with

Point Interpolation: The number of final gather points to be considered for interpolation at a shading sample during rendering. Higher values smooth the final gathering result at little cost (maya f1)

Narann
09-12-2008, 03:05 PM
It's often overkill to use both GI and FG
I maybe don't understand but it's a good option to use FG when rendering GI no?

lauras
09-12-2008, 04:33 PM
It's often overkill to use both GI and FG - and as mentioned filter just filters out extreme values, Point Density and Point Interpolation should be the ones you play with

Point Interpolation: The number of final gather points to be considered for interpolation at a shading sample during rendering. Higher values smooth the final gathering result at little cost (maya f1)

I believe that utilizing FG & GI together allows you to avoid any extreme values for either one and yeilds a very realistic result. I have found it much easier to work with the two together than either one alone. Especially GI, the FG helps to smooth everything out really well. I think what pushes people to not use both is the process of combining the two. It's a delicate balance of quality and render time and it takes practice to acheive good results for both.

To each his own, of course!

L

HJ-panorama
09-12-2008, 05:59 PM
hi


as Laura said, It is always a good idea to use GI and FG both together,.. that is a proven way to get a realistic result...

Here are some tests of my scene... I boosted up some accuracies either in GI and FG and did correct the radius of photons in both.

well, the results are not so bad but not 100% perfect too..

the problem that I had before ( the filter number in FG ) still exists.. too much annoying..
but the good news is, I decided to not to use it at all :)

the image "Look04" shows the other problem , the floor's material is a regular MentalRay Mia Material X...
which unlike the basic blinn shader has nothing to play with to control the amount of photon interaction and photon related properties like color, transparesy ... other stuff...

instead it has something like overal weight of FG and GI slider, FG quality and FG weight...
as you see the floor has a great expell of photons over the walls, I lowerd the overal FG and GI weight of Mia material but still has a strong spell ....

dont' know why It is not applicable..

thank u very much


PS: Laura: very funny characters... good luck!

lauras
09-12-2008, 07:24 PM
Mia Material X...
which unlike the basic blinn shader has nothing to play with to control the amount of photon interaction and photon related properties like color, transparesy ... other stuff...

instead it has something like overal weight of FG and GI slider, FG quality and FG weight...
as you see the floor has a great expell of photons over the walls, I lowerd the overal FG and GI weight of Mia material but still has a strong spell ....


Hi,

I believe you can plug a mib_photon_basic into the Photon Shader slot of your Mia SG node. That should give you some photon control. I'm not positive how well this would work though. You can also try a geo override, disable FG or GI receive and/or cast on the floor geo.

http://img.photobucket.com/albums/v140/laura0666/Work/PhotonicMaterial.jpg

HJ-panorama, I think those images look great so far, keep up the good work and thanks for the compliment!

L

Narann
09-13-2008, 12:11 AM
All like laura!
Use photon basic node controlling the color of photon (I use it once because my mia textures was too high and photon rendering was too long so it's a good idea).

And about pictures, there are very cool! :D
I prefere the "red-sunshined" mood :)

Good luck!:wavey:

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