How to make a scrollbar tint my color picker?

Question

I created an RGB scrollbar color picker but I also want to add something that tints the color so they can make it lighter or darker. I'm unsure on how to go upon this. Thank you:)

Private Sub bsbar_Change()
Me.cbtxt.Value = Me.bsbar.Value
End Sub

Private Sub cbtxt_Change()
Me.cpimg.BackColor = VBA.RGB(Me.crtxt.Value, Me.cgtxt.Value, Me.cbtxt.Value)
End Sub

Private Sub cgtxt_Change()
Me.cpimg.BackColor = VBA.RGB(Me.crtxt.Value, Me.cgtxt.Value, Me.cbtxt.Value)
End Sub

Private Sub cpassign_Click()

End Sub

Private Sub crtxt_Change()
Me.cpimg.BackColor = VBA.RGB(Me.crtxt.Value, Me.cgtxt.Value, Me.cbtxt.Value)
End Sub

Private Sub gsbar_Change()
Me.cgtxt.Value = Me.gsbar.Value
End Sub

Private Sub rsbar_Change()
Me.crtxt.Value = Me.rsbar.Value
End Sub

Private Sub ScrollBar1_Change()
'This is the tint scroll bar that I want to use to tint the cpimg.backcolor
End Sub

Private Sub UserForm_Activate()
Me.cpimg.BackColor = VBA.RGB(Me.crtxt.Value, Me.cgtxt.Value, Me.cbtxt.Value)
End Sub