Photons again

[Chenarch]

Hey Tomas and others,

Back on Photons again! And now trying to use photons in a MUCH

Larger interior (similar to scale of Blackpool rendering used in

EIAS3D banner.

Couple of questions.

1) I blocked off window openings (where Area Lights are which are generating photons). Will photons escape through here? Do I need to block off these openings with transparent objects?

2) I'm getting a lot of splotchiness on walls, whereas last June, when I was getting smoother walls. I have tried w GI on and GI off. Also now

getting render lines near ceiling lights I've not gotten before...

3) Renders are with:

photons>Always vis+database+Always

Direct: 80

GI: No skylight, only Rev Illum one bounce

Many thanks,

Richard

[Tomas Egger]

Ola Richard,

Send to me your project..

Thanks

Tom

[Chenarch]

Hi Tomas,

Thank you for taking a look... I tried to send but my email

always got rejected...

I have posted on ftp too..

Richard

Ola Richard,

Send to me your project..

Thanks

Tom

[Tomas Egger]

Ola Richard,

Which name and which folder? :)

Thanks

Tom

[Chenarch]

Ola Tomas,

I have emailed to you the FTP location etc... thank you very much for

helping!!

Best regards,

Richard

Ola Richard,

Which name and which folder? :)

Thanks

Tom

[Tomas Egger]

Ola Richard,

Please, take a look, I did a GI version, dont forget to turn your lights caches in Permanent, you were using “Always”.

Thanks

Tom

v8_test-TOM.zip

[Chenarch]

Hi Tom!

Thank you again for taking a look at that. I've done about 100 test renderings now and getting a much better hang of it. I thought the "Lookup Radius" related to light source distance from subject. I think I'm understanding it better now.

I do have a question. I set up my scene (image posted) using a sun casting primary shadows through a glass roof of a grain market. Then I set up a hemi-spheric light object which will cast photons. To be able to "see" the sun light rays, the light object (which covers the glass roof basically) has to be transparent. Then when I turn on the light object and make it shoot photons, I have to make the light object opaque again so it can be fully luminent. Then I've tried going back to "Sun" only, and the sun rays are no longer there until I turn off light object and start all over. Question: Does the process of baking the photon stuff bake in the GI and the direct sun as well? Or, why is the Sun still there now that the light object is no longer transparent... ? Am I making sense?

Anyway the setup for this image is: 400K photons, Direct 20, Bounce 30, Control Distance 1070, Dens Diag 258K in 17.

Thank You!!

[Tomas Egger]

Ola Richard,

Some Tips:

- Turn off receive shadows for your transparent roof (it will speed the render).

- Dont use Environment or Mirror reflections, since you are using Raytrace in normal mode. (it will speed the render).

- Use your Hemisphere light Obj with less polygons possible, because each polygon will become a Area Light. (it will speed the render).

- Using Selection Sets (create a selection set to your Hemisphere light Obj) and exclude it from your Sun illumination, its the way to have to have your Photon dome + Sun acting together in the way you did, otherwise, make your dome bigger than your sun Distance. :)

- All Photons lights need to be Secondary + GI to work fast with transparencies and reflections and refractions.

If you have more doubts, upload the prj to me. :)

Thanks a lot

Tom

[Chenarch]

More great tips, here, Tom... it gives me a better understanding of how

to manipulate photons. Thanks!:)

Richard

Ola Richard,

Some Tips:

- Turn off receive shadows for your transparent roof (it will speed the render).

- Dont use Environment or Mirror reflections, since you are using Raytrace in normal mode. (it will speed the render).

- Use your Hemisphere light Obj with less polygons possible, because each polygon will become a Area Light. (it will speed the render).

- Using Selection Sets (create a selection set to your Hemisphere light Obj) and exclude it from your Sun illumination, its the way to have to have your Photon dome + Sun acting together in the way you did, otherwise, make your dome bigger than your sun Distance. :)

- All Photons lights need to be Secondary + GI to work fast with transparencies and reflections and refractions.

If you have more doubts, upload the prj to me. :)

Thanks a lot

Tom

[rvlna]

The stripped lines in the ceiling in the second image seems to come from glow using stripped rendering (using renderama ...)

Rvlna

Hey Tomas and others,

Back on Photons again! And now trying to use photons in a MUCH

Larger interior (similar to scale of Blackpool rendering used in

EIAS3D banner.

Couple of questions.

1) I blocked off window openings (where Area Lights are which are generating photons). Will photons escape through here? Do I need to block off these openings with transparent objects?

2) I'm getting a lot of splotchiness on walls, whereas last June, when I was getting smoother walls. I have tried w GI on and GI off. Also now

getting render lines near ceiling lights I've not gotten before...

3) Renders are with:

photons>Always vis+database+Always

Direct: 80

GI: No skylight, only Rev Illum one bounce

Many thanks,

Richard