Photoshop :: What's Alpha Channel & How To Use It?
Feb 12, 2004What's alpha channel & how to use it?
View 1 RepliesWhat's alpha channel & how to use it?
View 1 Repliesim trying to add an alpha layer or alpha channel to a bitmap and save in BMP format.
I am using Photoshop 6.
can someone tell me the easiers way to make an alpha tga file? Photoshop 7 can done alpha when i save to tga 32 bits, but in CS we have to do it manually...
View 1 Replies View Relatedany difference between alpha layer and alpha channel? I mean has to be right? I just don't know what exactly that would be if there is. I'm trying to figure out some more stable uses for computer graphics when building textures with alpha layer or alpha channels. So far I get a flicker from opengl bug when using alphas. So I'm wondering if I use Alpha layer and something with a solid color underneath the geometry if I could achieve a more stable result where alpha sorting. Possibly clearing it up where my alpha layered geometry stays on top vs bleeding through at times it seems.
View 4 Replies View Relatedwhat is an alpha channel and how do i access it?
View 1 Replies View RelatedI have created two masks with channels to use on an image. Now I want to combine the two channel masks into one to use. I made a new layer in channels of the composite masks which gave me an Alpha channel. The Alpha channels show the solid black paint lines where I filled in the selection voids. These solid lines affected the adjustment layers so I ended up doing some erasing at 50%. Not the shortest workflow direction. How can I combine two channel masks (selections) into a common selection and save as a new Channel?
View 7 Replies View RelatedI created an alpha channel with marquee tool on a colored backgound, by using "select > save selection", the alpha channel appeared at the bottom of the channel palette. I know the white part should represents transparency and the black part is opaque. But when I import this into the Adobe premiere6.5, the thing is reversed, I have to use "alpha channel" plus "reverse" option to get what I want - see through the "white" part. I heard there is an option in the photoshop with which you can define whether you want "white" is transparent,black is opaque or vice versa,
View 8 Replies View RelatedI have an image that I want to have an alpha channel even though it isn't used at all. Even if I save the image with transparency flag in "Save for web" (as PNG), Photoshop doesn't include the alpha channel with image because it's not been used. Is there a way I can overcome this (other than adding a single transparent pixel to image or using another program)?
View 7 Replies View RelatedIs there a way to export an alpha channel to apply it to new file?
View 5 Replies View RelatedOnce I create an alpha channel, how do I edit it? I have tried selecting and clicking the alpha channel, and then using the paintbrush tool. I understand that if I have a white foreground, painting should remove some of the mask, while a black background should result in the painting adding to the mask. But often nothing seems to happen when I paint. Or, at other times, the painting results in paint marks on my image but doesn't affect the "marching ants" and therefore doesn't affect the mask. I have already checked that my K setting in Color is at 0 for white and 100 for black. Using CS5 version 13.0 x64 with Windows 7.Â
View 2 Replies View RelatedI can't seem to find a way to edit (or at least delete) the alpha channel of an image with transparency in Photoshop.
Ctrl-clicking the thumbnail of the layer and editing it in the channels tab is not what I mean...
Take a gradient, from Red 100% Opacity to Blue 0% Opacity. After I saved the gradient as a PNG, how can I for example use the levels adjustment on the PNG's alpha channel?
If I open the image in After Effects there is an option to control the alpha channel. That's quite embarrassing if a video software can edit the alpha channel and an image software can't...
I've attached screenshots to demonstrate what I mean.
I am trying to select the aplha channel (and make it a selcetion ) by using the command +mouse click but I only get the black selected not the white. So i have to invert selection, which is annoying. Am i missing something? this worked 2 weeks ago and now it has changed.Â
View 3 Replies View RelatedI'm developing a tile based game, I have basic ground tiles, and above these tiles can be objects. My game engine supports objects with an alpha channel, where the alpha channel is used for transparency:
alphachannel 0 = completely invisible pixel
alphachannel 255 = opaque pixel
alphachannel between 0 and 255 means the object and the background tile below that are blended, like semi-transparency.
This is useful to give the objects soft edges, and for semi-transparant fire, ghosts, and other nice looking effects. Code:
I have an image that I created in Photoshop CS3 with a drop shadow on it and transparency around it. I need to save it as a 32-bit TARGA file with an embedded alpha, so that the transparency and drop shadow work when I bring it into my video editing software, but when I save it out as a 32-bit .tga it doesn't save an alpha with it. I seem to remember Photoshop automatically creating an alpha from your transparency when you save out a 32-bit .tga. What am I doing wrong?
View 11 Replies View Relatedhow to I can copy only the alpha channels!
This is the instruction manual of the template:
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Once you have completed the painting work on your Texture Template, be sure to save it in its original form as a layered .psd document. Then, "flatten" the image, and save as a .bmp file with the name you wish to use for your paint scheme. Example: "DFB58_N12345.bmp". This name indicates that the template is for the DreamFleet (DF) Baron 58 (B58), and the N1234 is the registration number you painted on the aircraft. If you are doing a livery for an airliner, you can substitute the name of the airline for the registration number.
The name is not important, and DreamManager will work with any name, however we suggest a logical name so that you and others will know what the texture is. With little doubt, after all this painting work, you may wish to share your texture with others by uploading it to a file library, thus, a logical name will help identify it.
With your Texture Template now saved with a proper name and as a .bmp file, it is now time to prepare the Alpha Channel template.
Re-open the .psd version of the template in your paint program, and using whatever means you feel comfortable with, copy the entire alpha channel only to a new document. Once in the new document as a standard image layer, flatten the image, convert to grey scale if necessary, and then save this file as a .bmp file, the same as you did with your Texture Template. Use the same name that you used with the Texture Template, except add the suffix "_A" at the end of the name. If you have done this properly, your alpha channel template will be the same size as your Texture Template (typically 4096 x 1024).
Example:
Name of your Texture Template: DFB58_N12345.bmp
Name of your Alpha Channel Template: DFB58_N12345_A.bmp
when a copy is made of one of the channels be it the red channel , the new channel that is created will automatically be named alpha 1, but on my photoshop it will be called red copy . Do I have to name it alpha 1 or is there a setting I have to make.
View 1 Replies View RelatedI am looking for a mean to edit (not create and then edit) an already existing alpha channel in a PNG file (for example). Here is the scenario: load a PNG file with a existing transparency layer created with some other application ( I see the usual checker board behind some transparent regions of the image)select a region ( lasso, rectangle, ....)change the transparency (alpha) of those pixels only, do not change anything else in the reste of the image (ex: make a region more transparent or more opaque). I do not want to edit the RGB content of the pixels, I want to edit their alpha value directly.save back the file to a PNG file with modified alpha value.
View 36 Replies View RelatedExporting an image out of Maya with an alpha channel is easy, but getting Photoshop to reconize the alpha channel is not. The windows viewer, and the picture viewer on the mac reconizes it but not in photoshop which is wierd.
View 5 Replies View RelatedI have a PNG file created in Photoshop and I need to save it with an alpha channel for web purposes. I tried 'Save for Web & Devices' and selecting the Transparent box.
Then, after saving, when I select 'get info' for the file it says there is no alpha channel. I'm stumped I can't seem to create an alpha channel from within Photoshop while I'm editing.
I'm trying to put some text on a glass using 3d functionality of Photoshop. Is there any way to do so? On non-transparent material it is quite easy I can choose color of material then put texture with some text on a model. But how to put a non-transparent text texture on a transparent material?
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I mean something like that that [i used a picture from Daniel Presedo's video tutorial and added text with distort and warp
CS5, OS 10.6.6, 2.93 GHz Quad Core Intel Xeon
Making a mask from a selection the not-selected area is 95% black, not 100%.
So the not-selected area IS affected if the mask is applied, say using an adjustment layer.
Is there a preference somewhere, or a key command that was inadvertently applied?
When I have an image in 8 bits per channel, its grayscale alpha channel is in 8 bits (256 levels). But when I have an image in 16 bits per channel, is its grayscale alpha channel in 16 bits (32.768 levels)? They are a lot to make a selection...
View 7 Replies View RelatedI have a need to edit the channels independently (the values in my image mean things numerically rather than just what it looks like visually - so I need to edit the grayscale values in each of the R - G - B - and A channels seperately).
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I've searched through google and other forum posts and others bring up the concept of not understanding alpha versus transparency - but I have yet to see an explanation that fully explains what I'm experiencing.The closest was [URL]... But while I saw the exact same symptoms being described, the specific question was never really answered.
While, I'm specifically working with an RGBA image, below is a screenshot of a PNG that demonstrates the exact same behavior or symptom. The screenshot below represents the PNG inside GIMP and PS CS4. BTW, if you'd like to see or play with the image yourself, you can grab the same image at [URL]...
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GIMP, interestingly enough loads the PNG as expected - I see the transparency of the image treated as a true alpha channel.In PS CS4 however, the transparency seems to be somehow embedded in the Red - Green - and Blue channels; but NO seperate alpha channel.
I can create the alpha channel through Select - Load Selection - Layer 0 Transparency - and pasting that into a newly created alpha channel - but the color channels still have the transparency mixture symptom - rather than showing the JUST the color component of that channel. (Note the channel differences of the GIMP's Red Channel versus PS's Red Channel - Said in another way, the yellow ball in the upper left of the image should have a red value of 255, so the Red Channels grayscale upper left ball should be white like it is in GIMP, rather than Gray as it is in PS).
I haven't found quite the right explanation. As best as I have gleened "Alpha", which can be applied to any kind of channel, typically is in reference to transparency - and is applied as a document-whole transparency (as opposed to transparencies applied at a layer level - such as a layer mask).
I created an alpha channel for a selection and saved the tiff file. When I reopened the file the next day, I couldn't find the saved alpha channel and the load saving option was greyout. I tried the same process a few times and without any success.
View 3 Replies View RelatedBeen doing this for years... from After effects CC Composition, Save frame as, File, Photoshop, RGB+Alpha etc - and its worked fine exported with transparency like you'd expect.
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Updated Photoshop CC this morning and suddenly alpha channel not being recognised...Bug...or have I gone mad in the last 24 hours??
I have a series of files in which I improperly modified the selection set prior to saving the selection, and now around the intended viewable area there is a hazy artifact that seems to correspond to where I manually edited the selection using Quick Mask (prior to saving).
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In other words, within the area of the alpha channel that should be invisible, there is actually a visible, unwanted grey-ish artifact, and I think it's related to how I was using the brush to edit the selection in Quick Mask before saving.
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Now I am unable to edit the alpha channel, although Adobe's own website says that in order to edit an alpha channel, all I need to do is select the alpha channel (which I am doing) and then paint at 100% black or white with a brush to either include or exclude parts of selection set.
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When I choose the brush and start painting at 100% black or white, nothing happens and I can't figure out what is happening.
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The exact steps that I'm taking are below:
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1) click on alpha channel (visible and ready for editing), all other channels only visible not active.
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2) selecting the brush at either 100% black or white
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3) attempting to paint to alter the alpha channel (I've tried painting on the actual alpha channel in Channels, and I've tried painting on the alpha channel as it appears in Layers, and neither works for me).
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CLARIFICATION:
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I actually am able to "edit" the alpha channel HOWEVER I cannot remove the hazy artifact. I can use 100% black or white to remove the pink/light red areas on either the actual alpha channel (in the Channels area) or as it appears in Layers, but I cannot remove the areas that are grey-ish (well I can paint them white but I can't paint them black, i.e. fully pink).
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A teacher showed me a quick fix process that basically involves activating the alpha channel, inverting the selection, and then deleting everything outside of the alpha channel, and then resaving the file. That worked at one point, but now that quick fix is not working either (I am just ending up with a completely visible, white space around the intended visible area, rather than an invsible area).
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EDIT (07:22 3.20.13) Also, if you look at what Photoshop is registering as the actual alpha channle, it doesn't match with what I'm seeing above, that is the black and white alpha channel appears to be as expected, and there is not the weird distortion that I'm seeing above in the pink/grey image.
Is there anyway to save out an Alpha Channel Separately from the color? I just want the alpha channel as an image file. How can I do this?
View 1 Replies View RelatedI'm trying to do something that I could previously do with other image software. I want to 'paint' the transparency of a layer using the alpha channel. So when I paint black on the alpha channel it makes that part of the layer completely transparent, and white makes it completely opaque (and grey shades are in between). From what I understood of the help, this should be possible by just creating an alpha channel and painting in it. But when I try and then click back to display the RGB channel to look at the changes I've made, nothing actually changes. Whatever I seem to do to the alpha channel it doesn't actually affect the layer's transpancy at all.
View 3 Replies View RelatedI creat an alpha channel it shows up as white on my Photoshop Version 6 while my friend's alpha channel comes up in black on Photoshop CS. Obviously each is a default setting. How do you change the alpha channel color from white to black and vice versa.
View 5 Replies View Relatedsimple terms the following options in the JPEG2000 dialogue box :
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-Wavelet Integers and Float. Explain wavelet in idot proof terms? What is the difference between the two types of wavelets?
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-Tile size. What does it refer to when it says Tile? What's a tile in this instance?
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-Region of Interest. What does "controls the quality within the image by using an alpha channel" mean?
Saving selections and alpha channel masks?
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