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jmkupka
04-30-2007, 04:00 PM
In LW9, I'm modelling a clear plastic bottle. The front label is clear, with opaque white lettering and a simple bright red dot above it . No problem knocking out the clear background of the label (layer mask in Photoshop).
How can I get the graphics to be 100% opaque when they are applied to the color channel of the clear plastic? Tried putting a copy of the image in the transparancy channel, it gives it a little help but nowhere near opaque.
Any ideas would be great.

Giacomo99
04-30-2007, 10:20 PM
You could try cloning the object and use a clip map, with the label parts remaining opaque and the rest "clipped". If you have intersection problems, make the clipped bottle slightly larger --.1% on all axes should do it.)

Good luck.

BazC
05-01-2007, 12:40 AM
Tried putting a copy of the image in the transparancy channel, it gives it a little help but nowhere near opaque.
Any ideas would be great.

You're putting a colour image in the transparency channel? If so, that's where you're going wrong. Most colours will be interpreted as a shade of grey when placed in the transparency channel. You need a black and white version.

jmkupka
05-01-2007, 05:38 AM
Sorry Baz, you're right. I changed the image to black and white for the transparancy channel.
I tried stacking several layers of the image, as well as cranking up on the layer opacity. All this does is start to bleach out the red dot.

BazC
05-01-2007, 06:00 AM
I've just had a play with this and I'm having similar problems, I feel it should work so I wonder if it's a bug.

If I inverted the transparency map and set the layer to subtractive I got the result you're looking for though.

jmkupka
05-01-2007, 06:43 AM
I'm trying that, but no luck yet. Typical, trying to hit a home run with a new client, and I get hung up on this. If I wasn't under the gun timewise, it would be a better learning experience.

Thanks very much though, & please don't go away yet (lol).

jmkupka
05-01-2007, 06:49 AM
Giacomo, thanks for the tip. It's the first time I've worked with the clip map. Seems like it should work in theory, but no luck yet. Thanks again

Giacomo99
05-01-2007, 09:33 AM
Giacomo, thanks for the tip. It's the first time I've worked with the clip map. Seems like it should work in theory, but no luck yet. Thanks again

If it were me, I'd just do the logo on a separate pass.

My experience is that clients like their logos very bright and shiny, and it's nice to be able to punch the logo up without frying the rest of the image.

jmkupka
05-01-2007, 09:58 AM
Exactly, the text & logo must pop. So I delete everything but the bottle & set it to 0% transparency.
It'll make the copy 100% opaque, but won't it also fill the areas in between text?
Also, how do I combine passes... is it done in Photoshop?
Sorry you have to hold my hand on this one... I really am sort of competant.

Exception
05-01-2007, 10:34 AM
Seems to work fine for me,
Can you post the scene, some screen shots, or some illustration of what you're trying to achieve?

Giacomo99
05-01-2007, 10:57 AM
Rendering in passes is a concept little too complex for me to describe in detail here, although the principle is simple: What you would do in this case is turn all of the lights off in the scene and assign a 100% luminous white surface to the objects you want to isolate. Then you render out an image and use that render as an alpha-channel to select that object in Photoshop (or AfterEffects.)

Having typed that, it sounds like the problem could be that you're using the image map itself and not its alpha channel as your transparency map. The transparency map you're using is a greyscale image that's 100% white in the opaque areas and 100% black in the transparent ones, right?

gerry_g
05-02-2007, 06:04 AM
The other mistake people make is failing to leave the transparency channel set to zero, because they don't understand the clip map is providing the data for that function instead.

gerry_g
05-02-2007, 06:58 AM
Silly thing to write, it's not working cos glass needs transparency and the clip map don't, U need to dupe the polys where the label is and offset them by point whatever of a mil just so as they are clear of the glass and apply your clip map and color map to this surface with no transparency cos the clip map does it for you. On a good day even I can get things right ;-)

jmkupka
05-02-2007, 07:47 AM
Thanks Gerry, this is what I ended up doing & it worked perfectly. Thanks everyone for your help.