Pb translucency mesh

Bonjour, je réalise une petite Pan dont le corps est en material opaque et la queue est en mode translucide, afin d’avoir un petit dégradé sur le bout des plumes.
mais à cause des deux matériaux différents la transition est horrible entre la queu et le body (voir screnshoot)

Hello, I’m making a small section whose body is in opaque material and the tail is in translucent mode, in order to have a little gradient on the tips of the feathers.
but because of the two different materials the transition is horrible and can be seen completely between the tail and the body (see screnshoot)
body
if anyone has any idea thank you!

anyone for Help?