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stephenbuck415
01-26-2011, 10:23 AM
Hi everyone.

I just completed Ablan's video about gradients and am now working through the one on nodes.

I was wondering what is the best color setting to use to get the industry blue-screen color?

Thanks,
Buck

Dexter2999
01-26-2011, 11:04 AM
I know for sure but I would think it would be the purest blue you can get. As close to R-0, G-0, B-255.

But if you are using a "setting" meaning you generating the content from a computer, I would also think that you wouldn't use Blue screen because you wouldn't be pulling a Chroma key. You would want to use an Alpha key. So render in a format such as TGA 32 or PNG 24 (I think?)

stephenbuck415
01-26-2011, 11:36 AM
But if you are using a "setting" meaning you generating the content from a computer, I would also think that you wouldn't use Blue screen because you wouldn't be pulling a Chroma key. You would want to use an Alpha key. So render in a format such as TGA 32 or PNG 24 (I think?)

Hi Dexter, thanks for the reply. I understand the RGB settings, but am too much of a newbie to understand the other things that you have mentioned--that'll take more time.

I was curious about the blue-screen setting because blue-screens were used in the original Star Wars (and I understand that has changed today to become green screens when working with CGI). During one of Ablan's video's prior to the gradient/node set that I've just completed, he mentioned that a blue is used to help make dark backgrounds look larger. Although the blue from a light to accomplish that is going to be different than a blue-screen, I was hoping to learn whether or not there was an industry-standard to start experimenting from.

As I've just been introduced to surface editing, gradients, and the node editor, I wanted to play around with various color settings on objects and with lights to get a better experiential understanding of how things work.

Anyhow, your reply is helpful, and thanks for taking the time to reply.

Dexter2999
01-26-2011, 11:49 AM
Have you used Photoshop before?

"Alpha" is the transparency channel of an image.
If you look in the render in the image viewer of an object (that has no backdrop), you will see the "Image" drop down on the right side. Click it and the other option is "Alpha". You will see that the Alpha works like a mask. It blocks out everything except the object. So for compositing you don't have to key out the blue. The Alpha is a more precise mask for accomplishing the same thing.

UnCommonGrafx
01-26-2011, 12:26 PM
You are nice, Dexter.

stephenbuck415
01-26-2011, 12:37 PM
Have you used Photoshop before?

"Alpha" is the transparency channel of an image.
If you look in the render in the image viewer of an object (that has no backdrop), you will see the "Image" drop down on the right side. Click it and the other option is "Alpha". You will see that the Alpha works like a mask. It blocks out everything except the object. So for compositing you don't have to key out the blue. The Alpha is a more precise mask for accomplishing the same thing.


I'm a newbie with PS as well, currently going through Deke McClelland's Photoshop One-On-One series on Lyda.com. Alpha channels have not been discussed (yet).

I'm gaining an excellent (beginners) understanding of LightWave as I progress through the material, and community members like you are helping make the learning process much easier than it would otherwise be.

Thank you

JeffrySG
01-26-2011, 08:58 PM
http://podcasts.creativecow.net/multimedia-101-podcast/what-is-an-alpha-channel

Here's a simple video explaining alpha channels.

toby
01-28-2011, 10:12 PM
You would want to use an Alpha key. So render in a format such as TGA 32 or PNG 24 (I think?)
( just to clarify ) 24 bit formats ( 8 bits of each R,G and B = 24 ) like PNG24, TGA24 etc. do not have alpha channels, you need 32 bits; the alpha is another 8 bits, bringing the total to 32.

Dexter2999
01-28-2011, 10:55 PM
See, I knew the bit about TGA being 32. But I know that when I output from Illustrator PNG-24 has a checkbox for "Transparency". It doesn't say PNG 32, but I never dug around to find out the spec's of the format.