Selecting Shadow of an object photographed on white seamless background

[MrP0rt3r]

Hi,

 

I tried searching the forums for the answer, but nobody seemed to need the thing I do. The thing is, in my work there's a repetitive task of extracting objects/products photographed on white seamless background in such a manner to save its shadow separately. So extracting the object in AP is as easy as in PS, but how to select the shadow so I can then place the object with its natural shadow on a different background?

 

The method I use in PS is to CMD click the RGB channel icon to select the image highlights, then CMD+I to invert the selection (to select the shadows), then I create a new layer and fill it with black which gives me only the shadows in the image, but they sit in a separate translucent layer, so I can place this shadow on any background in future. Then I cut out just the object/product, and have it on a separate layer above the shadow, with full color and opacity. This way I can place the object with its shadow wherever I need, be it a color background, a gradient, a texture – doesn't matter because the object is opaque and the shadow is semi-transparent and falls off naturally.

 

I know AP is different from PS and I don't really want to do this the same way, just to get the same result. How do I do it?

 

Thanks a lot in advance :)

[MrP0rt3r]

I think I just found the answer – sorry for asking silly questions.

 

It seems you do it very simmilarly to the method mentioned in PS:

1. CMD + Shift cllick layer icon in Layers panel to get Luminosity selected

2. CMD + I to invert this selection

3. Create new pixel layer

4. Fill it with black

5. Put the shadow layer behind the original layer

6. Cut out the object with preffered method (masking maybe?)

7. Put both layers on top of whatever you need.

 

Once again – sorry for asking questions I could find the answer myself. Maybe it'll prove helpful for someone else.

[JimmyJack]

All that sounds fine.

 

But if the original white background with shadow is fairly clean you might not need most of the steps.

Copy the product out (make sure it's on top) and set the original layer to multiply. Put anything you want underneath.

[MrP0rt3r]

Yes, this works fine, but only if you compose everything within AP or Photoshop. It does'n work if you need (as I most often do) to place the photo inside a vector application like AD or Illustrator. If you set the picture to Multiply there, the whole thing becomes transparent and that's not what we want.

[RPM Inspired]

Did you ever find a solution?