A method for producing hydrogel contact lenses, comprising the steps of: obtaining a first polymerizable fluid composition and a second polymerizable fluid composition, wherein the first polymerizable fluid composition comprises at least one first free-radical initiator, at least one first polymerizable material, and at least one photochromic compound, wherein said at least one first polymerizable material comprises at least one first polysiloxane vinylic crosslinker that has a weight-averaged molecular weight of about 5000 Daltons or higher and is present in the first polymerizable composition in an amount of about 40% by weight or more, wherein the second polymerizable fluid composition comprises said at least one second free-radical initiator and at least one second polymerizable material and is free of any photochromic compound; obtaining a lens mold, wherein the lens mold comprises a male mold half having a first molding surface defining the posterior surface of a contact lens to be molded and a female mold half having a second molding surface defining the anterior surface of the contact lens to be molded, wherein the female and male mold halves are configured to receive each other such that a mold cavity is formed between the first and second molding surfaces when the mold is closed; applying a drop of the first polymerizable fluid composition onto the geometrial center of the first molding of the male mold half, wherein the drop has a volume of about 5μL or less; dispensing an amount of the second polymerizable fluid composition on the second molding surface of the female mold half; closing the female mold half with the male mold half having the drop adhered thereon to form a molding assembly comprising the second polymerizable composition and the drop of the first polymerizable composition within the mold cavity; curing the second polymerizable fluid composition and the drop of the first polymerizable composition to form an unprocessed silicone hydrogel contact lens having a central photochromic zone that has a diameter of about 13 mm or less, is concentric with the central axis of the unprocessed silicone hydrogel contact lens; separating the molding assembly into the male and female mold halves, with the unprocessed silicone hydrogel contact lens adhered onto a lens-adhered mold half which is one of the male and female mold halves; removing the unprocessed silicone hydrogel contact lens from the lens-adhered mold half; and subjecting the unprocessed silicone hydrogel contact lens to post-molding processes including a hydration process and one or more other processes selected from the group consisting of extraction, surface treatment, packaging, sterilization, and combinations thereof. obtaining a first polymerizable fluid composition and a second polymerizable fluid composition, wherein the first polymerizable fluid composition comprises at least one first free-radical initiator, at least one first polymerizable material, and at least one photochromic compound, wherein said at least one first polymerizable material comprises at least one first polysiloxane vinylic crosslinker that has a weight-averaged molecular weight of about 5000 Daltons or higher and is present in the first polymerizable composition in an amount of about 40% by weight or more, wherein the second polymerizable fluid composition comprises said at least one second free-radical initiator and at least one second polymerizable material and is free of any photochromic compound; obtaining a lens mold, wherein the lens mold comprises a male mold half having a first molding surface defining the posterior surface of a contact lens to be molded and a female mold half having a second molding surface defining the anterior surface of the contact lens to be molded, wherein the female and male mold halves are configured to receive each other such that a mold cavity is formed between the first and second molding surfaces when the mold is closed; applying a drop of the first polymerizable fluid composition onto the geometrial center of the first molding of the male mold half, wherein the drop has a volume of about 5μL or less; dispensing an amount of the second polymerizable fluid composition on the second molding surface of the female mold half; closing the female mold half with the male mold half having the drop adhered thereon to form a molding assembly comprising the second polymerizable composition and the drop of the first polymerizable composition within the mold cavity; curing the second polymerizable fluid composition and the drop of the first polymerizable composition to form an unprocessed silicone hydrogel contact lens having a central photochromic zone that has a diameter of about 13 mm or less, is concentric with the central axis of the unprocessed silicone hydrogel contact lens; separating the molding assembly into the male and female mold halves, with the unprocessed silicone hydrogel contact lens adhered onto a lens-adhered mold half which is one of the male and female mold halves; removing the unprocessed silicone hydrogel contact lens from the lens-adhered mold half; and subjecting the unprocessed silicone hydrogel contact lens to post-molding processes including a hydration process and one or more other processes selected from the group consisting of extraction, surface treatment, packaging, sterilization, and combinations thereof.