Transparent tshirt with shadows

[Somcy]

Hello gurus,
I have a little problem where i stucked.
I need a transparent tshirt, but i need to keep the shadows and wrinckles.
I need it for a mock up.
I can do to recolor just the tshirt, but i can't do to be transparent.
I need this one

to be this, just with the shadows and everything else.

I downloaded all the google servers, but i didn't find anything.

Thanks, if anyone can help.
Somcy

 

[colleague]

you can select the t-shirt and put it on a new layer
make the shadows very dark with a level adjustment-layer and a layer mask
and then lower opacity to 20 a 30 %

and save it as a png

 

[IamSam]

Use a channel selection on a darkened tee and then duplicate the selection to it's own layer.

 

[Somcy]

Thank you guys, im fighting with it. I feel myself completly stupid. I think im tired. Check it tomorrow