Question Transparent and Depth of Field approach?

I wanted to try and do a work around for rendering a transparent sheet that would work with the Depth of Field post effect in the built in pipeline. So I did a simple depth only shader and set the render queue to happen after solid geom but before transparent and it uses the offset option in the shader to render the depth a little bit further from the camera, and then a second material to to actually render the transparent sheet using the standard transparent shader. But this is not working, has anyone else tried anything else to get a transparent object to work with depth of field?

Below is the simple depth only shader I am using in case I have missed something that someone might spot.

Code (CSharp):

1. Shader "Depth Only"
2. {
3.     SubShader
4.     {
5.         // Render the depth after regular geometry, but before transparent things.
6.         Tags { "RenderType"="Opaque" "Queue"="Geometry+10" }
7.        
8.         // Don't draw in the RGBA channels; just the depth buffer
9.         ColorMask 0
10.         ZWrite On
11.         Offset 0.5, 1
12.          
13.         Pass
14.         {}
15.     }
16. }

 

Bgolus' answer here has the issue explained
https://forum.unity.com/threads/depth-of-field-issues-with-transparent-render-queue.1041292/
The DoF is using the shadow pass, so the shader needs a shadow caster pass and should be in or below AlphaTest - your example is, so should be fine.
A simple way to copy in a shadow caster pass is to add

Code (JavaScript):

1. Fallback "Mobile/VertexLit"

At the end of the shader.

More great info from the BGolus here
https://forum.unity.com/threads/dof-on-transparent-shader.604363/