Forest Canopy Specular Bloom


#1

Hey guys, I checked around for a dupe of this but I wasn’t able to find it. Anyways, I’m attempting to create a fall tree canopy in 3d Studio Max. The tree has been modeled and textured and I have geometry leaves with multiple opacity maps, in other words, it takes a while to render.

I’m trying to get a bloom, diffuse glow, whatever you want to call it to show through the canopy. Any ideas. I’ve tried video post, but the effects aren’t great.

I want it to look like this photo:
http://toadstool.se/photos/2002/.1024x768/map/07/08-Amazon,Peru/24-Forest_Canopy.JPG

Notice that it has it transparent leaves where the leaves closer to are actually brighter.

But the bottom line is, I’d like to have some specular bloom/diffuse glow on it. Ideas?


#2

umm… can you show us your attempt? I’m not sure why the bloom is a problem. It’s really just blur, pretty simple. As for the leaves translucency, well you’ll have to consider either faking it or doing it the heavy way with SSS.


#3

the fastest way to do it is in compositing.
easy way would be make “in After effects” a duplicate layer and lower the saturation. then put the lowered sat layer on top of original. use maxium filter to remove some of your image and blow out whites. blur the image, then use your color modes and opacity to make the look your after…

for a more accurate results:
if your going to use mental ray for max. look in the mental ray materials thread for max
it will show you how to unhide the lume “glare” mental ray shader. it does exactly what your looking for just a lil heavy to render. look for pholicals post about unhiding “glare”

you have to be using max 6

kurt


#4

As a general rule of thumb, any lens or film surface effects like the blooming you see through the canopy, lens flares, yadda yadda should be added in the composite. The reason for this is twofold, firstly they are are not effects of the objects themselves but efects of the capture mechanism, this is the land of the comp, use your 3D to create “the real world” i.e. before it hits the camera. The second reason is that if you add these effects in comp you’ll be able to control the results much better.

One thing which may help you is to render a higher dynamic range (if your comping package supports this) as you will get better blurring, glowing effects. The reasoning behind this is well explained here by the father of HDR Paul Debevec

Hope that helps, all the best,

Andrew


#5

This may help you with the diffuse glow part:

http://www.neilblevins.com/cg_education/specular_bloom/specular_bloom.htm

and as far as the translucency goes, I’d use the transluceny property of the raytrace material since the leaves are so thin:

http://www.neilblevins.com/cg_education/translucency/translucency.htm

Check the part at about figure 4.

  • Neil

#6

Thanks for all the help guys, the video glow effect doesn’t really look good in this case because in a photo, the bloom will actually show through the leaves and also bloom around the edges. I can’t seem to get both effects in one shot. I suppose I can composite the two images together using photoshop but I’d like to try and stay away from it.

In any case here’s what I have. The red arrow points to a position that I would actually like to have a bloom.

BTW tell me what you guys think about the image. :thumbsup:


#7

You could also try to work from this tutorial : a simple back light method taht can be tweak with a DOF + Lens Glow

http://www.highend3d.com/global/tutorials/backlightglow/

(no matter which software you use)

I hope it helps :beer:


#8

Photoshop Composite: I think I’m done with this one… yeah right, when am I ever done :stuck_out_tongue:


#9

Did you tried the back light tutorial I sent you the adress for this image?
To criticize this picture :

  • the blur to be composited to bloom is to much grainy.
  • the bloom effect not strong enough, you should add a volume light to get some rays through the leaves.
  • the translucence shader you used looks more like simple transparency. If you’ve right used a translucence sading, I think you have to tweak it and even paint a translucence map (less trnaslucence at the leaves “braches/veins” you know). Let have a look at this article : http://www.deathfall.com/tutorials.php?op=showcontent&id=73 do not switch to renderman, just get some good information from this analysis.

Anyway : good work mate :beer:


#10

Here’s two quick ways to achieve a nice bloom effect, in 3D Studio & Photoshop:

3DS Max:

Use the blur post-filer and tick the Luminosity only section, and play around with the settings. Considering you said you have long render times, I’d recommend against this method as you’d have to re-render the whole thing again to tweak the effect. So, the better method is…

Photoshop:

  • Duplicate the original layer. Rest of the operations are done in this new layer over the original background.
  • Adjust Levels so only the brightest parts (i.e. the ones you want bloomed) are visible. Rest of the image is black.
  • Set the layering method to Screen. You’ll immediately see the brightest parts getting extra bright.
  • Add Gaussian blur. Play around the effect to get the bloom radius you want.
  • Fiddle with layer opacity and color saturation to put in the finishing touches.
  • Simply use the eraser tool to get rid of the bloom in the unwanted areas.
  • Add Lens flares, filters, radial blur etc. to give streaking effects and DOF faking.

Simple as that and takes less than five minutes. The result is something like this, a bit over the top, but the principle is the same (hope you don’t mind - I’ll take the image down if you want):


#11

:beer: Thank You everybody for all your help. I ended up using some photoshop tricks in the end and produced a result that I’m pretty satisfied with.

Posted in this thread: http://www.cgtalk.com/showthread.php?s=&threadid=148454


#12

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