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AWM3000
31st March 2004, 01:02
I have a question about Photoshop, so I hope that the combined expertise on these forums can help me clarify my question!

My question has to do with transparency: where exactly is the transparency information of a particular channel or image stored? Most images have multiple channels, such as RGB or CYMK. In a Photoshop RGB image, there are three channels, each one cabable of containing 256 shades of red, green, or blue. I noticed that each channel also contains transparency information. This makes it seem like there is also some sort of hidden alpha channel or information that determines each channel's transparency. However, in a standard RGB image, there is no displayed alpha channel, even though individual layers, and even the image itself, can have transparency. How does this work--where is each layer or channel's transparency information stored?

The reason I have this question is because I'm creating images with alpha channels, and wondered how I could use photoshop's existing ("hidden"?) channel information to directly create an alpha channel. (clicking "select layer transparency", making a new channel, and filling the selection with white is my current method, but it is not 100% accurate)

blessindaultras
1st April 2004, 07:02
Originally posted by AWM3000
I have a question about Photoshop, so I hope that the combined expertise on these forums can help me clarify my question!

My question has to do with transparency: where exactly is the transparency information of a particular channel or image stored? Most images have multiple channels, such as RGB or CYMK. In a Photoshop RGB image, there are three channels, each one cabable of containing 256 shades of red, green, or blue. I noticed that each channel also contains transparency information. This makes it seem like there is also some sort of hidden alpha channel or information that determines each channel's transparency. However, in a standard RGB image, there is no displayed alpha channel, even though individual layers, and even the image itself, can have transparency. How does this work--where is each layer or channel's transparency information stored?

The reason I have this question is because I'm creating images with alpha channels, and wondered how I could use photoshop's existing ("hidden"?) channel information to directly create an alpha channel. (clicking "select layer transparency", making a new channel, and filling the selection with white is my current method, but it is not 100% accurate)

RGB the transparency can be found on the right hand side on the layers section up the top there u can change the transparency or even double click on the layer and change the transparency that way :up: this shud work for all channels!!

Adil
26th April 2004, 16:32
1. set the transparency of your layer
2. create a new empty layer
3. merge both layers
result: you just applied the transparency setting to the layer's alpha channel.
be careful though, you cant remove the transparency later.

Greatsilverwyrm
12th May 2004, 14:24
Originally posted by Adil
1. set the transparency of your layer
2. create a new empty layer
3. merge both layers
result: you just applied the transparency setting to the layer's alpha channel.
be careful though, you cant remove the transparency later.
spot on :up: