3D HDRI shadow map placement using Photoshop

[cgminds]

Hi, i got a jpg file that is the shadow of the under of a car. Rendered with maxell. Maxwell gives me the alpha map layer and shadow map layer to do the final compose with photoshop. I just can't figure out how to omit the white from the actual darker shadow. Any help?

 

[IamSam]

Hello cgminds and welcome to PSG.

It could help if you uploaded the file/image so we can have a look at it.

 

[cgminds]

Absolutely! Thank you for helping! I have these 4 files output but maxwell.

 

[cgminds]

I know the shadow plane was too small but the cut off part won't be seen. Id like to know the process then once learned I'll go back and re render the shadow. I've searched online and found out how to generate these files but they never explain the photoshop compose part. Hehe. So I'll ask the experts here.

 

[MrToM]

Try this...

1. Place the 'Car' above the 'Ground', so your first layer is 'Ground' and above that the 'Car'.
2. Use your 3rd image as a MASK for the Car layer.
3. BETWEEN these two layers create a new layer and fill with black.
4. Use your 4th image as a MASk for the Black layer but INVERT it.

Technically you have everything there its just the 'Shadow' map thats reversed.....the shadow should be white on black.

Sorry I didn't use your images but the site download speed is so slow it would just take too long.

Regards.
MrToM.

 

[cgminds]

Hmm.... ill Give that a shot. i used to use brazil rs and it was easy to get the shadows. With maxwell i have to port to photoshop and that's not my strong area. Thank you for the suggestion.

 

[MrToM]

Like this...



Note the MASK for the black layer is just the inverse of your shadow map.

I've just noticed your 'Car' is already on a transparent background so you don't even need to mask that....even simpler!

Regards.
MrToM.

 

[cgminds]

Beautiful ! Thanks a million! Only thing I'm trying to figure out is how to apply the mask. Step 4. Very new to this . Also i did invert the shadow.

How do you get that chain link from pic to shadow pic?

 

[cgminds]

Yup... i will skip that part. Car is already clipped. I'm using photoshop CC. Im going through the menus... trying to get that chain link thing that binds both pics.

 

[IamSam]

I just set the layer mode of the shadow layer to multiply.

 

[MrToM]

Thanks Sam...that was easier than the four page explanation I just deleted!

Regards.
MrToM.

 

[cgminds]

Ohhhh! That it! Thank you. I finally did it! Feel soo dumb! Thank you again! You are awesome!

 

[cgminds]

Hopefully this page shows up on google search when people search for this solution. I searched everywhere! Could not find anything. Thank Sam!

 

[IamSam]

Hopefully this page shows up on google search when people search for this solution. I searched everywhere! Could not find anything.

What would be a more appropriate title for your thread? That would help in any future Google searches.

 

[MrToM]

Although you've sorted this now its important to remember that not every map can be applied by changing just the blend mode.

An example of this would be the 'Z-Depth' map which would need to be a MASK and selected as the source from the 'Lens Blur' Window.

Regardless of this example, learning how to use masks wouldn't be a bad thing to do.

Regards.
MrToM.

 

[cgminds]

Change it to what ever you feel is best. I couldn't come up with something shorter. Maybe "HDRI shadow placement through Photoshop "?

 

[cgminds]

Although you've sorted this now its important to remember that not every map can be applied by changing just the blend mode.

An example of this would be the 'Z-Depth' map which would need to be a MASK and selected as the source from the 'Lens Blur' Window.

Regardless of this example, learning how to use masks wouldn't be a bad thing to do.

Regards.
MrToM.

Yup.... I got to dwell more with photoshop.