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rhino:softgilightingusinglightdomes [2015/09/14]
127.0.0.1 external edit
rhino:softgilightingusinglightdomes [2016/01/20] (current)
sandy
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-====== ​This page explains how to get soft GI lighting using lightdomes ​in Flamingo ​======+====== ​How to Get Soft GI Lighting Using Lightdomes ​in Flamingo======
 Check out the formatting tips on the right for help formatting and making links. Check out the formatting tips on the right for help formatting and making links.
  
-Use the template below: 
  
 +**Rendering with lightdomes**
  
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-**Soft ​GI Lighting ​using lightdomes**+There has been a lot asked and shown on the Flamingo Newsgroup about lightdomes. ​ Personally I wouldn'​t be without them (until someone adds GI to Flamingo). ​ Needless to say I've learned a lot about using these things over the last few years. So here are a few snippets to help folks along (previously unreleased material follows..) ​ I will come back and add and amend as and when I have time.
  
 +**Soft GI lighting using lightdomes**
  
 +First, all comments below relate to lightdomes using point lights.
  
-----+One of the big problems with lightdomes is shadow artifacts. ​ One way to solve this problem is to use a larger number of lights, but anyone who has tried this approach knows that its impact on render times can be extreme. And even then it doesn'​t completely solve the problem.
  
-**Rendering with Lightdomes :** 
  
 +For me a more successful route is to use **Source Radius**. ​ To access this you need to have soft shadows turned on and may need V1.1 SR4 or V2.
  
-there has been a lot of stuff asked and shown on the Flamingo NG regarding lightdomes. ​ Personally I wouldn'​t be without them (until someone adds GI to flamingo that is... ).  Needless to say I've learnt a lot about using these things over the last few years so hear are a few snippets to help folk along (previously unreleased material follows..) ​ I will come back and add and amend as and when I have time.+**How to do it**
  
-**Soft GI Lighting using Lightdomes :**+Insert a lightdome by whichever means you usually do it -- David Rutten'​s scripts and UVe are good ways.  Start with something small so that you can see the effect easily -- I suggest 20-40 lights. ​ Once inserted look at the dome in plan view and roughly measure the greatest distance between two adjacent lights.
  
-First off I all comments below relate ​to lightdomes using point lights.+Select the lightdome and go to **Properties** Under **Source Radius** enter the value you have just measured. ​ This will effectively make every point light a sphere the size you have entered. The effect of this is all the lights overlap to form one //big// light, rather than 20-40 separate ​lights ​doing their own thing.
  
-One of the big problems with lightdomes is shadow artifacts. ​ One way of solving this problem is to use a larger number of lights but anyone who has tried this approach will know that its impact on render times can be extreme and even then it doesn'​t completely solve the problem.+You can leave your samples pretty low (5 works fine, though you could try it lower..). They jitter at about 20.
  
  
-The image above shows the typical artifact problem (please excuse the standard of the image - not got a lot of time to spend on this just now!!  :'​( ​ )+Although you can still see some artifacts their effect is greatly reduced.
  
-For me a more successful route has been to make use of '​Source Radius'​. ​ To get access to this you will need to have soft shadows turned on and may possibly need V1.1 SR4 or V2. +Don't expect it to work in miraculously quick times - it won't. Lightdomes ​never dobut it will be quicker than trying to render with a lightdome with 200 lights in it.
- +
-**How to do it :** +
- +
-Insert a lightdome by whichever means you usually do it - David Ruttens scripts and UVe are good ways.  Start with something small so that you can see the effect easily - I would suggest 20-40 lights. ​ Once inserted look at the dome in plan view and very roughly measure the what appears to be the greatest distance between two adjacent lights. +
- +
-Select the lightdome and go to '​Properties'​ - under source radius enter the value you have just measures. ​ What this will do is effectively make every point light a sphere the size you have entered - the effect of this is all the lights overlap to form one '​big'​ light - rather than 20-40 separate lights doing their own thing. +
- +
-You can leave your samples pretty low (5 works fine you could try it lower though..) and jitter at about 20. +
- +
- +
-Although in the image above you can still see some artifacts their effect is greatly reduced. +
- +
-Don't expect it to work in miraculously quick times - it won'​t ​- lightdomes ​never do but it will be quicker than trying to render with a lightdome with 200 lights in it.+
  
  
 ---- ----
  
-**Addendum ​:**+**Addendum**
  
-This technique ​can be used with very few point lights to achieve more even lighting.  ​try playing around with source radius' ​and see what difference it can make.+Use this technique with very few point lights to achieve more even lighting.  ​Try playing around with source radius and see what difference it can make.
  
  
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-**Want to know more?** 
- 
-Just click [[rhino:​otherlightingissueswithlightdomes|here]] 
  
  
  
rhino/softgilightingusinglightdomes.txt · Last modified: 2016/01/20 by sandy