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illicit
05-02-2005, 09:35 PM
Maybe this is a simple concept, but I haven't gotten good results yet. I need a nice looking thermometer for a web project, but nothing else in the image. I understand all of the normal concepts when working with glass, refraction, HDRI, reflection, air space, etc. I just don't know how to make it look right with nothing else in the scene.

Any pointers would be greatly appreciated.

Thanks
dave

Sastira
05-02-2005, 09:52 PM
Glass is not going to look right if it doesn't have anything to reflect.

If it is the only thing in the scene, stick an ambiguous reflection/refraction map on it.

T-Light
05-03-2005, 09:14 AM
I'd be thinking of a well placed placed luminous polygon with radiosity turned on. (You'll see this effect a lot on auto/car renders etc)

illicit
05-05-2005, 08:08 PM
Not working out too well so far. I still must be doing somethign wrong. This image is with HDRI lighting, reflection map, curved backdrop, ray traced everything, but no radiosity. This was about 6 hours on a 3.4Ghz HT. With radiosity turned on it barely moved after 10 hours. Maybe it's time for fprime :)

http://www.3doverdose.com/dl/thermometer_01.png

I think I'm goint in the right direction but I'm stll missing something.

Thanks for your input.

dave

illicit
05-05-2005, 08:44 PM
I don't understand why everyone else's renders with radiosity look great while mine look like horrible speckled trash...

dave

cgolchert
05-05-2005, 09:03 PM
If that is the only thing in your scene you probably don't need radiosity.

coremi
05-05-2005, 11:04 PM
u should check this out.


http://www.geocities.com/CollegePark/9315/lw/tip4.htm

harlan
05-05-2005, 11:11 PM
I don't understand why everyone else's renders with radiosity look great while mine look like horrible speckled trash...

dave


I don't understand why everyone renders with radiosity just because they can when 9 times out of 10 it clearly isn't needed.

Ztreem
05-06-2005, 07:22 AM
Here's a quick test, 10 min modeling and setup, 15 sec render. No radiosity!

An easy setup is:
Place a white box above your object with 100-500% luminosity.
Make a grey cuved surface behind your object as a background.
Make your object reflective and use fastfresnel or gradients for the fresnel effect.
Render.
I hope it helps.

illicit
05-06-2005, 11:16 AM
I don't understand why everyone renders with radiosity just because they can

harlan, I hear you on this. But if you look above, it was suggested so I thought I'd give it a try.

Ztreem, that looks tons better than mine already. I will definately try it out tonight when I get home.

dave

monovich
05-06-2005, 11:45 AM
another great technique for good studio-like reflections in something like this thermometer is to use a gradient background. Don't use the default (sunset) colors, just make it white to black/grey.

example:

harlan
05-06-2005, 02:25 PM
harlan, I hear you on this. But if you look above, it was suggested so I thought I'd give it a try.

Oh, I'm sorry Dave, I was implying you. Perhaps I should've written the post a little better. I was referring to Chris' comment. Sorry for the confusion.

harlan
05-06-2005, 02:27 PM
BTW Dave, your theromometer looks good; just kinda like it's encased in ice. :)

harlan
05-06-2005, 02:27 PM
You FPime show-off!!! :)




another great technique for good studio-like reflections in something like this thermometer is to use a gradient background. Don't use the default (sunset) colors, just make it white to black/grey.

example:

illicit
05-06-2005, 06:52 PM
Getting better.......

Ztreem
05-07-2005, 05:28 AM
This one looks better in some ways...
I don't know what look your after, but I Think this one is a little bit too dark and I also think you should skip the HDR image reflection or change it to another one.

You could try to increase the luminosity on the red thing to make it a bit brighter.

I Hope it helps. :cool:

Carm3D
05-07-2005, 10:17 AM
Did you model "air" polygons?

Duplicate your glass polygons in another layer, make a new surface name for it, call it air.. Hit "f" to flip the polygons. Make it 100% transparent.. No refraction or reflection. Copy it back to your original layer if you like and then try your refraction render.

Carm3D
05-07-2005, 10:44 AM
The hollow cube on the right uses air polygons. The one of the left does not.

Note that the polygons in your thermometer that are touching the mercury will not need air polygons.

This was rendered with all bells and whistles active (trace transparency, refraction, reflection, etc)

Carm3D
05-07-2005, 11:06 AM
..And some happy caustics (http://www.happy-digital.com/cowstic.asp) thrown in just for fun. :cool: