im lost…can u explain it again?! you want the alpha or not?
I needed the alpha channel to make a shadow effect on my flattened image. Unclick the eyeball of the alpha channel in the channels palette, and the shadow disappears. Click the eyeball and ther shadow appears in the image. Is that clear?
Here’s the problem. when i printed the image, it came out as two pages. 1. the image WITHOUT the alpha channels shadow effect. 2. the gray scale alpha channel itself.
I could not get the image to print with the shadow. Nor could i get it to print as one page, unless I actually went into the channels palette and trashed that alpha channel.
I was actually wondering if this was a bug, or perhaps a corrupted file, since I’ve used alpha channels in the past and they never printed as separate pages of an image. The only reason i wrote this post, is that I am wondering if, in the process of creating the image (or the alpha channel), i might have I accidentally clicked some "function" that turned the alpha channel into a printed page.
im confused as to how you have done it in the past, the alpha channels aren’t meant as actual production parts of an image theyre more like your working drawings, something to help you along the way.
Their preview in PS is just for on screen purposes, they wont seperate as plates automatically unless set to spot, and even then their effect is guestimated, they cant display the actual effect of the ink in relationship to CYMK.
If you have the alpha, why not convert it to a selection, make the shadow from that? you can do it on a layer if you need that freedom, and then you can have the choice.
yah i understand everything you are saying. I told you how i fixed the problem, saving a copy with no alpha channels, and then basically recreating the gray-scale shadow effect as a layer.
I was just curious what, if anything, i had accidentally activated to make the gray scale gradiant "image" of the alpha channel print as an actual page. And,as i say, i couldn’t get the flattened image to print as it looked on my screen until i had deactivated the alpha channels. Maybe it was just a corrupted file. anyway, thanks for your help.
Jim:
Perhaps the confusion lies in a misunderstanding of the purpose of Photoshop’s Channels.
Your C, M, Y and K channels are designed to each print using their designated Cyan, Magenta, Yellow and Black inks. (RGB channels are translated into ink-values by your printer-driver when you print to an RGB ink-jet printer.) A Spot Color Channel would create a fifth color-plate to print a Pantone ink or a spot varnish.
On the other hand, an Alpha Channel does not relate to any ink-output and acts only for storing such things as selections which you might want to use to create Layer Masks etc. while building your image.
If you got the Alpha channel to print, could you in fact have changed it from an "Alpha" to a "Spot Color" channel or did you change your file into Multichannel mode?
I’m not sure i agree that an alpha channel has no ink output. When you look at them in the channels palette you see a gray scale image. And yes, i do understand that it is not the color gray that the alpha channel actually represents. However my printer was printing that gray scale representation as an actual image (as a second page in the print out) and i couldn’t get it to stop.
So maybe I accidentally activated a spot channel or multichannel mode. I started this discussion looking for an explanation of why photoshop printed the alpha channel when i thought I had never asked it to.
So maybe I accidentally activated a spot channel or multichannel mode.
Well you can surely find out if you did.
Double click on the channel. Do you get the spot channels options dialog or the channels options dialog that will allow you to turn your channel to a spot channel?
When you choose image>mode is CMYK checked off, or is Multichannel?
Of course none if this would explain why you got the extra channel as a separate page even if it is a spot channel.
Wouldn’t printing composite out of Photoshop print the spot color merged into the CMYK? And if your printer driver allowed you to print individual channels (separations0, then you would have gotten 5 grayscale printouts, not a CMYK composite and an extra print for the other channel.
When you talk about "unclicking the alpha channel option" in your original post what do you mean? Where exactly is this option?
I notice that if visibility is checked for an alpha channel, that it will output as a grayscale "second page".
You can check this (without wasting any ink!) if you use "Print with Preview" and then click the Preview button.
So, if you don’t want that second page to print, make sure that alpha channels are UN-checked when printing.
a few details just to conclude this discussion.
1. At the time, I was working in RGB, outputting 1200 dpi proofs to an epson inkjet.
2. The epson driver does allow me to print the separations. i actually tried that just to get a better idea of what was happening.
3. I think you got the answer, Ann. I must have inadvertantly checked "visibility".
4. The option to eliminate alpha channels appears as an option in file>save as. Since the new file seemed to fix the two page printout, i trashed the original, and recreated the shadow effect with a gray scale layer blended to the original image via a linear burn.
