How can I create white smoke in yellow liquid?

[McGugan]

Hello out there!
I need some help in creating a material that I can apply to a cylinder. The cylinder is transparent like water but with a layer of white smoke in the bottom half of the cylinder. I have created everything but the white smoke.

I have attached a PDF showing the keyshot rendering which I have prepared and photos of how it looks in real life.

I look forward to hear if someone can help me with this task.

[edwardo]

I'm not sure, but I bet graduated opacity maps will work to some degree. Also I guess the 'smoke' material will have zero specular, so bump the refraction index right down, and put the specular colour to black. Failing that.... photoshop?

Ed

[McGugan]

Hi Ed,

Thank you for the suggestions. I have tried a graduated opacity map, but I can't get it to look anything like the real life results.

I will keep working on it, but if someone has any other ideas, I am all ears.

[OK]

I would have to agree with Edwardo, I think the opacity map is the way to go. Here is what I came up with in a few minutes so with some tweaking I'm sure you should be able to get the result you want!
I also added the opacity map I made.

[McGugan]

I have been working on the problem and have tried your proposal. Here is what I could get out of using a opacity map.



Test 1-I used your image and applied it to my internal part as an opacity map. The problem is that I have to have the product on a white background because the renderings will be cut and pasted to create a users guide. As you can see the smoke affect dose not show up clear enough, plus it is too transparent (even after several different adjustments). The other issue is that the liquid is a light yellow color which also gives the smoke a yellow tint.



Test 2-I tried changing your image to give the smoke a yellow color. I then created another image that was just a light yellow color. I applied the yellow colored smoke as an opacity map and the light yellow color as a color map. This did not work so well either.



Test 3-I found a photo in iStock of some fog. The photo is black & white. In photoshop I changed the background color to a light yellow, then I created a new layer and filled the whole layer with a yellow color, then adjusted the transparency of this layer so the the fog was visible. This added a yellow tint to the fog. I then saved it as a jpeg and applied it as a color image (only) to my part.



Here again is how it looks in real life. Just for a comparison.

With some more adjustments I think this could work. It is not exactly what I was looking for because the yellow area is not transparent. The image covers the out side surface of the cylinder, so if I place something behind the device it won't be visible through the yellow area.

I don't know if there is another way in which the yellow area could become transparent, like liquid, without using a opacity map?

[TpwUK]

I would model the cloudy part as if it was liquid. Pulling the control parts on the top part of the cloud cylinder shape, then use Dielectric material or possibly a Translucent one.

Martin

[OK]

Is this more like what you had in mind?
Also I don't think you want to put the opacity map on the yellow liquid, just make that glass dense or something and add a new part for the smoke where you add the opacity map.
The thing is that if you have a white background the 'white' smoke actually doesn't look white (see your pictures) but is actually quite dark compared to the liquid/background.

[TpwUK]

That looks more like what i was referring to... Nice effort OK

Martin

[McGugan]

Hi OK,

Your solution looks very close to what I am looking for.

I see what I was doing wrong now. I was trying to achieve this look using one solid cylinder. But as you explain, I need to use two different cylinders.

Thank you very much for this insight. I will try it and post the results.

Have a nice weekend and once again thank you.

[OK]

No problem, good luck! Looking forward to see the result!