I'm playing around with a different B&W conversion workflow in photoshop. Essentially, you do the conversion three separate times in three layers. Each channel mixer layer is predominantly the green channel, or the red, or the blue (usually in that order, though different orders in the layer stack work too). You can then mask out, say the green layer, to change something locally to be more red channel dominated. Under and in between the layers you can shift tones, put photo filters, etc etc. And you can further play with the blend modes.... It is the most flexible and therefore the most time consuming way to do this. But hey, I like it.
(the same basic approach, but resulting in three tones b&w layers, gives you the Technicolor method.)
Super Takumar 28mm f/3.5
Super Takumar 28mm f/3.5
Yashica Mat 124G, Fuji PRO160S
Yashica Mat 124G, Fuji PRO160S
Super Takumar 28mm f/3.5