[paxreid]

I have done a quick search and didn't find any information on this..so sorry if I missed it and this has been resolved somehow.

Working in 3dMax7, importing geometry from FormZ 5.5.3 and Sketchup 5. Both programs we export as DWG and insert into 3D max for rendering. note: I have not had any issues when exporting from FormZ, so this may have to do with exporting from Sketchup. One of our summer interns uses sketup and is contributing to this scene.

So..

If I start a new file from Max and create two boxes, set the time and place per our location and render, I get the correct representation of sunlight, etc.

Then I import the mesh from Sketchup and move into position and render (all using a generic matte maxwell material) ..I get no direct sunlight anymore, and strange shadows show up.

Any ideas on what is happening? Why would inserting geometry mess with the environment?

Thanks in advance for any assistance.
Paxton.

[KurtS]

check your pivot y value, this case looks a bit like this one:
http://www.maxwellrender.com/forum/view ... hp?t=23251

[paxreid]

Thanks Kurt..I did read that thread, but missed the connection. I don't think it has to do with the pivot point, but with the location of geometry.

I think that the NL sun model has the sun set at about 3500 feet in the Z direction, and models that stray anywhere outside of 0,0 do not render correctly.

Here are a few quick tests showing the same model, same time, same coordinates with a different Z value. I had thought with all this talk about "real" sky , you need to have your model at the correct height (to get the "pink" out )

Anyway...apparently the sun is a lot closer than the 149694072 km it should be because just by adjusting the height of your model by the thousands of feet, you dramatically change the angle of altitude of the sun. Go figure....NL should look into a better model (unless I am doing something terribly wrong here)


So I assume that for "accurate" sun it the model HAS to be at 0,0,0. Any deviation from that point is thus biased?

Paxton.

[zoppo]

[JTB]

OK, we really need an answer on this
So, here goes accuracy...
Not that I care much but since we 're supposed to buy unbiased renderers and having so much waiting time, we must have correct results.

[hyltom]

What time have you set for those rendering? I'm asking you this as the shadows of you last example (Ground at 0 feet) seems really accented means the sun is low in the sky already...maybe it's 5 PM or 6PM. In that case, i will not be surprise that at 3500 feet there is no more sun.

Have you try to do the same test with the sun at noon?

Edit: 3500 feet is only 1000 meter (around)...that's really low actually. In my mind i was thinking in meter (3500 meter)...So there is definitly something strange here.

[paxreid]

9:00 AM Lake Elsinore CA
GMT -8.
July 2nd


Do you think that the sun angle at 3500 is significantly different than at sea level? I would think that the sun altitude would be almost identical the for both. Now if it was really low..and there were mountains,etc things could be in shadow, but the light wouldnt be coming from below.

[numerobis]

phys sky + sun
01.07.2007 12:00 gmt
camera ISO100 8.0 1/500

plane (~80x80m) at 7000m

...spotlight on!!!

...so do we have to decide whether we prefer a not so pinky sky or correct shadows!?!
and what if my building is at 2000m?

[paxreid]

Harder to tell at noon since sun is directly above you...it appears to be an emitter set around 15,000 at noon. It seems the earlier the day, the sooner the emitter is below your plane (9:00 am, 3500 feet).

This explains why the model has to be at 0,0,0 if there is an emitter centered around that instead of your model. Doesn't this compromise any accuracy of location? Just curious.


Shot at 2007-07-03

[paxreid]

numerobis....you beat me!.

Hard to believe that the "Sky System" is basically a spot light that is so close it could compromise any accuracy that is built into maxwell with KML files,etcetc....but I don't know enought about it to know if that is normal or program limitation.

[zoppo]

what beats me is ... the thread has been "officially handled" by moving it in another section - but still no answer.

[Renato Lemus]

Maybe we have caught NL doing something "biased" to reduce rendertimes, at least it looks like cheating IMHO.

[tom]

If we were lying, you wouldn't complaining about the speed. Think twice...

[Renato Lemus]

Don't get me wrong, I'm not telling you or someone at NL are lying. I'm tryin' to understand what is happening with the sky system.