I have been playing around with some lightning bolt models I built in Cinema 4D.
The whole scene is Terragen, with some color/contrast adjustments in PhotoShop.
The sun is at -5 degrees, so most of the light is from the lightning, which is why the foreground is so dark.
Well I'm off to go camping, be back on Tuesday the 5th.
This is a great beginning. Use reference photos...please update so we can keep seeing this.
I like it. Very real looking lightning. I have a problem with the clouds. For some reason they just don't look right.
Maybe they are lit to much. I understand the lightning would light them a little. But this is too much.
Keep up the good work.
This is a good start. I have been trying to get some convincing lightening too. Initially I too tried to do a night scene so I could get the cloud illumination effect, potentially very impressive indeed! The main issue I ran into was that the light source would naturally extend along the length of the bolt and not be limited to the extremities. Ideally a well modeled bolt with its luminance value set to something suitably large may do the trick (I would guess up in the millions!). Lightening a scene only from a luminance source theoretically should work but I found the various quality levels had to be set too high to get anything respectable in a reasonable amount of time. (ie lots of noise !!)
I think your bolt needs to considerably thinner, not necessarily real world size (a few cm only ) but maybe more like a meter in width and quite a lot more complex, more tendrils etc. I don't think we're going to get any kind of "glow" feature in terragen anytime soon so that will be a post process job.
I look forward to seeing this progress. :)
Enjoy your camping, going anywhere nice?
Richard
very nice work....I'll keep an eye on this!....enjoy your trip!
The clouds look good, but a bit to solid in my opinion.
The Lightning doesn´t start where we see it first.
Try to put the lightsource more into the cloud and let the cloud glow from within -that would be my idea.
But I bet it´s not that easy, is it?
It is already very impressing as it is.
Best regards,
Jan
Quote from: Mahnmut on July 31, 2008, 10:20:14 AMThe Lightning doesn´t start where we see it first.
Try to put the lightsource more into the cloud and let the cloud glow from within -that would be my idea.
The lightning usually starts from the ground and goes up :P
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I like it very much. It's nice to see some renders with overcast and a more dramatic setting. I'm actually working on a lightning scene myself.
If you'r gonna work more on this, please post the updates.
Quote from: sjefen on July 31, 2008, 02:40:13 PM
Quote from: Mahnmut on July 31, 2008, 10:20:14 AMThe Lightning doesn´t start where we see it first.
Try to put the lightsource more into the cloud and let the cloud glow from within -that would be my idea.
The lightning usually starts from the ground and goes up :P
Lightning is a discharge of electricity caused by two opposing electrical charges, one in the thunderclouds and one at ground level that balances the charge from the clouds. The discharge itself happens when the strength of these charges reaches a peak and the energy is transferred through the ionized air. So it doesn't really start in the clouds or at the ground, it's kind of shared between the two.
Hi PG
What you are saying is correct. This is basically energy of + and - charges and from what I've heard the earth has the negative charge and the clouds have the positive. Electricity must go from - to + so this means that the lightning must travel from the earth to the clouds.
There are of course exceptions where for example the lightning never hits the ground and stuff like that. I don't remember what happens in those cases.
This is what I've always heard and it makes sense to me. If this is not true I'd like to hear the real answer tho.
- Terje
That was not what I was talking about, but anyway:
As far as I know there are invisible flows of charge, ("spherrics"?) that emerge from high points or points of great conductivity on the ground, explaining why the actual visible lightning "knows" where to hit.
The visible lightning most times moves from the sky downwards.
What I wanted to say was that there might be parts of the lightningbolt at the moment depicted that we can´t see directly but that light the cloud from within.
not exactly what we are talking about, but an incredibly cool photograph in my opinion:
http://news.nationalgeographic.com/news/2008/05/photogalleries/volcano-photos/
Best Regards,
Jan
Lightning takes many many many many forms, there is no ignition point so a lightning bolt can occur anywhere that positive and negative points exist at high levels. Cloud to ground strikes are the second most common, the first being intra cloud lightning (otherwise known as flash lightning, well that's what I call it anyway). Ground to cloud discharges happen but only at a recorded rate of about 3%.
That's an insane pic mahnmut.
I have tried lightning scenes a couple of times and have got reasonable results putting light sources inside clouds. There was quite a lot of fiddling to get the position and strength of the lights and the cloud and atmosphere quality settings needed to be pushed way up, probably why I never finished any of the scenes. ;D
How do you get the lightning bolt itself to emit light. I'm still trying the portal storm thing but I can't get any light from it.
In the lightning bolt object, pump up the luminosity.
I tried values between 1 and 40 and it looks the same. I also tried the specular tab but to no avail. Here's what it's like so far. Please excuse the crappy clouds.
What is your object shaders basic colour? Is it black?
No light blue. It's the exact same material shader sonshine provided except I've changed the colour and luminance values.
This looked like it should work so I made some tests and it is working for me. I pushed the luminosity up to 128.
The first one shows the lighting on the ground and the second has a cloud layer, which works quite well. You might need to experiment with the GI settings, I just wanted to prove that it worked.
The .tgd files are there as well; you will probably need to fix the object path.
I assume you were after coloured lightning. This is possible
There is a complex relationship between the Luminosity Colour and the overall luminosity value. I can't begin to understand this, by now I must have made over a hundred tests and have listened to a lot of Messiaen, If my neighbour doesn't like Messiaen he can come and figure this out and be thankful that it wasn't a full on Stockhausen or Steve Reich problem. (Drumming on repeat. Nice ;D ).
For the example below I just took the second .tgd from my last post, opened the default shader attached to the lightning object and edited the Luminosity colour/value. I first ser the luminosity colour to < R=32, G=24, B=16 > and then set the luminosity value to 128.
If someone can explain EXACTLY how these values interact, (I assume that the diffuse colour plays a part), my neighbour will love you for ever.
Fortunately the values you set are saved. If you try to reset the colour you have to remember to reset the luminosity and like wise if you want to change the luminosity you have to reset the colour first. But they are preserved if you open a saved file.
This is dead cool; I wish I had tried it earlier, last week I spent hours trying to hide lights in the clouds, render times through the roof and results that didn't come near. Belgium!
Great work here. Last time I tried anything similar was a few terragen iterations ago, that time I think I was trying luminous windows and although it should have worked the whole GI side of the renderer just wasn't up to the job yet. Horrible speckles all over the place! Glad to see its all working now, er.. rather well actually :)
Richard
I think this works because the lightning models are big. Smaller points of illumination like windows get missed in the GI calculations. I couldn't get the real world scaled lamp on my tubular steel lighting column to cast light at all.
Tubular steel lighting columns, (Crap modern lampposts to you ):
http://www.ashundar.com/index.php?action=tpmod;dl=item379
I am sure that I read a comment from Matt about objects casting light but I'm buggered (Messiaen, Des Canyons zux étolies now. Oh and the large amount of fermented joy juice I have imbibed in the last few hours. ;D ), is not helping, These grins are not silly enough. ;D ;D
about any object being able to cast light.
The superportal is almost candesant in the amount of light it emits. I pumped the luminousity to 600 but I think it needs something else to give it the really powerful glow It looks a little lighter when the sunlight hits it but still little more than if I used a light diffuse colour. I'll probably add light sources up the shaft of the bolt and play around with the specular as well
Edit: Ok well increasing the specular to 150 and changing the colour to a light blue gave the outline a nice creepy blue aura but radiance was still non-existant and the rest of the object was still the same dark blue so I took the idiot route and increased the specular again, this time to 350. Unsurprisingly I didn't get the result I wanted. I did however get this Psychadelic :o
(http://img246.imageshack.us/img246/8065/psychlightme3.th.png) (http://img246.imageshack.us/my.php?image=psychlightme3.png)