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StOuen
05-13-2008, 07:57 AM
Hi, I am looking for a way to show the density of water as if there is a camera bobbing in the ocean <pls see attached>. I can get a underwater scene looking ok but its having the volume density whilst also viewing a above the sea environment. I did find a tut that looked like it did something on this but the link was down. If anyone knows if it still exists please let me know.

Thanks.

voriax
05-13-2008, 08:27 PM
You can get a similar effect using a dielectric surface with absorption. This one had a colour value of 248, 255, 255 and an absorption of 10. Also has refraction blur turned on and roughness set to 100 to get that murky look. It's a bit extreme if you want anything visible in the water, though, as you can see from the cylinder poking out in the lower right corner.

StOuen
05-14-2008, 12:57 AM
Spot on thanks. I am still getting the hang of the DiElectric stuff but your example looks the biz. It is to aid a transition from surface to undersea so will be comping in a different underwater shot later.

Thanks again! :thumbsup:

Ramon
04-21-2009, 05:27 PM
You can get a similar effect using a dielectric surface with absorption. This one had a colour value of 248, 255, 255 and an absorption of 10. Also has refraction blur turned on and roughness set to 100 to get that murky look. It's a bit extreme if you want anything visible in the water, though, as you can see from the cylinder poking out in the lower right corner.

That looks great! I have yet to work with LW's node system. I am still working on the old "layered" way. I assume you are using nodes correct? If so, could you send a screen shot example of your node network? Also, is this something you can do without nodes?
Thanks in advance!

Tobian
04-21-2009, 06:14 PM
Yes, you can use a gradient in the transparency channel set to 'surface thickness' and set it to multiply to your other transparency layers. At the 0m point make it white and set your depth to however far the ray has to travel to become opaque, and make that black.

As it happens I was just working on a nodal water shader over on Spinquad, so maybe have a play with that? http://www.spinquad.com/forums/showthread.php?t=25441 I set it up so you can see where the main controls for ray-depth, blurring, and ior are. For that I would probably separate out the refraction blur if you really want it to be that murky! :)

Ramon
04-22-2009, 01:25 PM
Yes, you can use a gradient in the transparency channel set to 'surface thickness' and set it to multiply to your other transparency layers. At the 0m point make it white and set your depth to however far the ray has to travel to become opaque, and make that black.

As it happens I was just working on a nodal water shader over on Spinquad, so maybe have a play with that? http://www.spinquad.com/forums/showthread.php?t=25441 I set it up so you can see where the main controls for ray-depth, blurring, and ior are. For that I would probably separate out the refraction blur if you really want it to be that murky! :)

Thanks for the your example jpg. Nice water but, yes, I would like that towards the bottom, it becomes "thicker" or less transparent. The problem is, since (in my work as well, I need it to be a side / top view) but I need to achieve that volumetric look to the water. That's much easier to do from a perfect side view but from this angle I need, I imagine that becomes more difficult to achieve with just shaders "faking it". I'm I correct?

Ramon
04-22-2009, 01:36 PM
Actually, now looking at voriax's image and it does look like what I'm going for just that my camera is slightly higher and angled slightly more down, thus I would think that there would be (in actuality) less transparency down at the bottom in the foreground as well as the background.

Tobian
04-22-2009, 04:49 PM
May not be clear in my pic, but that's exactly what it does! It's just more subtle an effect :)

Ramon
04-22-2009, 06:33 PM
May not be clear in my pic, but that's exactly what it does! It's just more subtle an effect :)

Hey Tobian,
Thanks man, I'll try it out.:thumbsup: