I've rendered an image in Bryce and then selected all the meshes and groups that I want to keep and then rendered a mask image. I'm a total newb to Photoshop. My question is how do I combine these two in Photoshop CS to get only what I have masked. If someone could give me a step by step or point me to a tutorial It would be appreciated.

The above image is very basic Bryce and will rely heavily on post work just so I can get some practice in using my new Photoshop and some really cool plugins I got my hands on.

 

 

 

I'd drop by the Photoshop forum here, they'll know more about the details..;)
I use something like Photoshop called the Gimp, which is an opensource clone.

Croowe, in PS, in the channels palette of your original render, create a new alpha channel. Copy and paste your mask render into that channel. When you ctrl-click that alpha channel, a selection will be made around everything that's white. You can then go back to your original render layer and hit ctrl-J to lift out that selection to another layer.

I have a tutorial using PS Elements 4, might be useful too.

http://www.thebest3d.com/pdp/tutorials/pse4

There is a single file in this case where the transparency mask (or its counterpart the opacity mask) is located in the alpha channel. But I'd assume you can also find this to work with a separate file in a greyscale image holding the mask. Just open both and either mask should become (hopefully) visible in the list when you try to build the mask from the file(s)

Open your ship and the mask. Double click  in ship pallette to turn it into layer, if not a layer already. Shift drag the mask over to the the ship image (clicking shift will put mask image on new layer exactly in the position of your ship layer) . On your mask layer go to the channels pallette. Control click the rgb icon. (Since your mask is just black and white, you could control click any of the channels.) You will see marching ants around your selection. Go back to your layers pallette. Go to your ship layer and click the add layer mask icon at bottom of pallette. Delete the top layer you used  (original mask) to create the mask. Ta DA!  If you need more help let me know.

- Open the normal render in photoshop.

• Doubleclick the layer and give it a name. this will promote it from background to floating layer.

• Go to the layers menu and add a mask

• Open the mask render

• In the mask render press ctrl+a to select the whole render

• In the mask render press ctrl+c to copy the selection

• Switch back to the normal render

• In the layer manager go to channels and select the mask channel and turn it visible (click the little square at the left to make an eye appear next to it, like the other channels)

• Press ctrl+v to paste the copy u made of the mask render into the mask channel

• Make the mask channel invisible again to lose the red overlay

• press ctrl+d to unselect the selection

And congrats ur done!

Orbital has a nifty little tut covering this in the tutorials sections here.

Aprilgem has the ticket here. It's the fastest and most simplest way of achieving this small triumph.

 

Just My two cents! I use painshop pro. but....

If you paste this foreground onto a darker sky you could end up with a light purple line around the edge where the mask picked up part of the sky behind. Whenever I mask I do my renders twice as big then shrink everything once I have all the layers put together. It helps remove aliasing lines around the mask.

Quote - Aprilgem has the ticket here. It's the fastest and most simplest way of achieving this small triumph.

 

Ironically enough, the technique I actually use the most myself in all of my work is the one described by Rayraz, as I like keeping masks or alpha channels linked with the layer itself. But it was easier for me to describe the channel palette way. ;-)

But everyone's way works just fine. I love that Photoshop provides so many ways to do the same thing. :)

Yes, I agree Aprilgem but for the Photoshop novice the way you specified is the fastest way without explaining that several other things can be done to bring in the mask into Photshop. A hands clean and very vaiable proccedure for the noobie.

 

Agreed, I use the other way too. a bit more complex, yet I like to keep all components in one place & lighten the folder.(heavier PSD, but no BMPs) ;)