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Krypton · Jul 30, 2002, 12:37 PM

I'm trying to construct some new toolbar buttons for an app, but I'm having difficulty exporting to a file format that will preserve the transparency/mask. I always end up with a white background imstead of the transparency I want (tried .tiff and .png)

Maybe someone could explain to me how to mask things and then export them (I am using Photoshop 4). I know this sounds a little vague but I've never used masking before.

I would be grateful if someone could point me in the right direction

godzookie2k · Jul 30, 2002, 10:10 PM

it really depends on what formats your software supports, but EPS with a clipping path should work...

Griggsy · Jul 31, 2002, 03:36 AM

Or save a tiff with an Alpha Channel, in pshop select the areas you want to mask (making sure they are active, ie the dotted line is moving around them) then goto the Channels pallete select the 'Save selection as Channel at the bottom of the pallete (circle in a square) this should then produce a new channel called Alpha 1, then just save as a tiff normally, if the alpha is masking the wrong bits youy can alter the channel by hiiting 'Apple key -I' to invert the selection, I always get it the wrong way round'.

Alphas if tight always produce the best results either in Quark or After FX, if you need any other help let me know

Ibson · Jul 31, 2002, 06:34 AM

When I'm creating graphics for Cocoa apps which require a mask, I use Photoshop's Export to Web function and export as a PNG-24. This is the quickest and easiest way to produce a masked image. Having said this, I don't believe PS 4 has that function

.

Krypton · Jul 31, 2002, 01:51 PM

<blockquote>quote:<hr />Originally posted by Griggsy:
Or save a tiff with an Alpha Channel, in pshop select the areas you want to mask (making sure they are active, ie the dotted line is moving around them) then goto the Channels pallete select the 'Save selection as Channel at the bottom of the pallete (circle in a square) this should then produce a new channel called Alpha 1, then just save as a tiff normally, if the alpha is masking the wrong bits youy can alter the channel by hiiting 'Apple key -I' to invert the selection, I always get it the wrong way round'.

Alphas if tight always produce the best results either in Quark or After FX, if you need any other help let me know<hr /></blockquote>Thank you, thank you - you don't realise how happy you've made me!

I can finally use my skills to do something useful.

Now here's my next question: I've successfully masked a simple shape from a one layer file, but how do I mask files with multiple layers - and most importantly for me, semi transparent layers that have drop shadows?

Once again, all help is much appreciated <img border="0" title="" alt="[Wink]" src="wink.gif" />

Griggsy · Aug 1, 2002, 04:09 AM

Well to do transparancy masks is just a whole world of fun, you will probably have to make an alpha for each layer, to keep it tight remember to press the apple key over the relevant layer in the layer pallette to exactly select all the content. As far as transparency use various levels of black to white, ie grey in the alpha channel to create a transaparent alpha. To do this select the content of your alpha in the channel pallete by pressing the apple key over the alpha layer in the channels pallete and then selct a grey and fill it, you will see the alpha colour weaken, which means you now have a transparent layer, I think.

Now with a drop shadow, if you have made it in pshop using the layer style option, rasterize this, by either using the rasterize command in the layer menu at the top, or make a blank layer and place it underneath the layer with the drop shadow and select 'merge down' from the layer pallete menu on the right hand side of the layer palette, accessed by clicking on the wee arrow on the top right of the pallette.

Once the shadow has been made part fo the actual layer and is no longer an effect, select the content of the layer, by preesing the apple key over the correct layer in the layer palette and clicking the mouse, this will select the content of the layer, now, just make an Alpha as normal and you should find that the alpha compensate for the shadow and masks it correctly with a feathered edge and a bot of transparency.

If you want to actuall use the alphas to determone selection of an object, use the Load selection option in the Select menu, this will load the Alpha as a selection.

Is that what you needed to know, let me know

Krypton · Aug 1, 2002, 12:27 PM

<blockquote>quote:<hr />Originally posted by Griggsy:
Well to do transparancy masks is just a whole world of fun, you will probably have to make an alpha for each layer, to keep it tight remember to press the apple key over the relevant layer in the layer pallette to exactly select all the content. As far as transparency use various levels of black to white, ie grey in the alpha channel to create a transaparent alpha. To do this select the content of your alpha in the channel pallete by pressing the apple key over the alpha layer in the channels pallete and then selct a grey and fill it, you will see the alpha colour weaken, which means you now have a transparent layer, I think.

Now with a drop shadow, if you have made it in pshop using the layer style option, rasterize this, by either using the rasterize command in the layer menu at the top, or make a blank layer and place it underneath the layer with the drop shadow and select 'merge down' from the layer pallete menu on the right hand side of the layer palette, accessed by clicking on the wee arrow on the top right of the pallette.

Once the shadow has been made part fo the actual layer and is no longer an effect, select the content of the layer, by preesing the apple key over the correct layer in the layer palette and clicking the mouse, this will select the content of the layer, now, just make an Alpha as normal and you should find that the alpha compensate for the shadow and masks it correctly with a feathered edge and a bot of transparency.

If you want to actuall use the alphas to determone selection of an object, use the Load selection option in the Select menu, this will load the Alpha as a selection.

Is that what you needed to know, let me know<hr /></blockquote>Thank you again, I've always wanted to make some cool toolbar buttons (amongst other things) and now I've succeeded - albeit a forward and back button for Chimera, but I should be able to do a whole set soon.