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vicky_1
03-01-2006, 07:40 AM
Newbe Q:What is the best way to get an image with transparency from 3d to PS?

Png retains the transparency while tiff, tga gives an alpha channel that i inv. select and delete to get the transp layer. But i can't do the same with objects that fade away in edges.
Don't have this trouble in Afx where the tga with alpha shows thru the layer below.
Hope i'm clear about my problem... or am i missing something?
scrimski
03-01-2006, 08:33 AM
I think you totally missed the concept of alpha-channels.
Why do you delete somth in whatever layer to make it transparent?
You can always use your alpha-channel as a mask for a layer, you don't have to delete anything(also works with fading edges).
In AE you can choose how the alpha of an image is interpreted, or can even ignore it.

For (not only) 3d output I prefer tiffs, for intrn purposes like previews or proxies I use png sometimes, depends on the amount of disk space I can access.
vicky_1
03-01-2006, 01:30 PM
Hi scrimski

I probably didn't communicate my problem clearly.

Simply, when i load a png file in PS, it shows the opaque stuff as is and the alpha area transparent. But with tiff and tga the same stuff shows the alpha area in white which i have to clear out myself so as to see layers below it. No such problem in AFX for the same images.
Am i missing some setting or prefs or something for PS?

Glad if someone can help. Thanx!
scrimski
03-01-2006, 03:25 PM
No, that's the way it is. You do not have the option to interpret an alpha channel directly in PS, so you have to wether delet or mask the transpare
nt parts(as defined by your alpha channel).
Ikarus
03-01-2006, 08:04 PM
Like scrimski said, that's just how photoshop treats them. If you plan on using your images as stills and mostly be using them in photoshop I would render them out as PNGs, as that is what I do. No need to select your alpha mask and delete when you use PNGs.
I haven't used renders much for animation or motion graphics, so I don't know if there is any advantages to using TIFs or TGAs.
vicky_1
03-02-2006, 06:30 AM
Thanx scrimski, Ikarus!

wow! And i assumed i didn't get it!

:rolleyes: now why would they allow that in AFX and not in PS?
jeremybirn
03-02-2006, 02:52 PM
It's funny, Photoshop's inconsistent behavior bothers me also, but the opposite way.

When I render a 4 channel image (red, green, blue, alpha) I always want to see those 4 channels in the channels palette, and want to be able to see and manipulate the whole image. Arbitrarily hiding parts of my image from me, or not showing the alpha channel, is totally uncool.

You don't need to delete anything. If you have an alpha channel and want to use it as a layer mask, just load the alpha channel as a selection, then click the "add layer mask" icon at the bottom of the layers palette. Then you have a layer mask that fully supports all the shades of transparency from the alpha. (this doesn't work for background layers, if you have a background layer duplicate it first.)

-jeremy
vicky_1
03-04-2006, 06:18 AM
Hi Jeremy!

Thats exactly what i wanted! Thanx and...:bowdown:

Vicky
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