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lightfoot97
10-03-2010, 01:22 PM
I am pretty confused about this ...

System/Software:
- LW 9.6, 32 bit
- winXP 32

Situationin the scene:
- 1 pointlight, diameter 4m, volumetric, no fall off
- 1 camera
- both parented to a NULL

Position of the NULL:
- Frame 1: Y = 0m
- Frame 20: Y = 12km

When rendering:
- Frame 1: everything is ok
- Frame 20: the light intensity dropped down remarkably!!

I havent done anything special, it should render the same. Maybe I am crazy, or I have a cursed machine. I'm not sure.
So please load the scene, make the two renders and tell me about my sanity ...

many thanx in advance for your help

prometheus
10-03-2010, 01:31 PM
I am pretty confused about this ...

System/Software:
- LW 9.6, 32 bit
- winXP 32

Situationin the scene:
- 1 pointlight, diameter 4m, volumetric, no fall off
- 1 camera
- both parented to a NULL

Position of the NULL:
- Frame 1: Y = 0m
- Frame 20: Y = 12km

When rendering:
- Frame 1: everything is ok
- Frame 20: the light intensity dropped down remarkably!!

I havent done anything special, it should render the same. Maybe I am crazy, or I have a cursed machine. I'm not sure.
So please load the scene, make the two renders and tell me about my sanity ...

many thanx in advance for your help

Im sorry,I havenīt checked your scene, but the first thought is that since your moving a volumetric light with a pretty small diameter 4m, compared to the distance your moving to at 12 km, isnīt that bound to make a difference on how the light intensity is perceived?

Michael

lightfoot97
10-03-2010, 01:40 PM
hello michael,

I have parented both (camera and light) to the same null,
so when moving the null, the distance between camera and light remains the same.

I only moved the null such a big distance, because the scene where I need the light has a pretty big scale ...

Danner
10-03-2010, 06:42 PM
That's because at 12km into space there is no atmosphere so lights can't brighten anything =P

Just kidding I have no idea why it's doing that. Would it be practical for you move everything else and keep the camera and light near the origin?

You could also parent everything to a master null and scale that down to say 20% I moved your null even further and the light eventually fades completely at about 14km.

Mr Rid
10-03-2010, 11:16 PM
Weird things happen in LW when you move that far out from 0,0,0. Voxels and IK also get wonky. Its some limitation in the math at that scale.

lightfoot97
10-04-2010, 08:23 AM
Thanks for the reply.

Now at least I know, that working in real world scale is not always a good idea ...
In future projects it will save me some time for sure.

As to my current project, I will have to find a workaround.
And I think the use of a master null, followed by a massive downscale could do the job. - Thanks for pointing that out. :)

Elmar Moelzer
10-04-2010, 08:35 AM
You can still work with real world scale, just make sure that the area of interest (the one closest to your camera) is also closest to the coordinate origin. LWs precision gets lower the further you move away from that origin. So if you have a range of mountains 15 miles away in the BG, the precision there will still be high enough for those mountains, but if you had a character standing on that mountain and you moved your camera there, it would get all weird and distorted.