Method of filling a mould with a glass gob through an opening of the mould, for forming a glass product in the mould, by using a delivery system for delivering the glass gob to the opening of the mould, the delivery system having an inlet, an outlet, and guiding means for guiding the glass gob through the delivery system, the method including the steps: a) depositing the glass gob in the inlet of the delivery system; b) guiding the glass gob by using the guiding means towards the outlet of the delivery system; c) depositing the glass gob from the outlet of the delivery system in the opening of the mould; d) observing the glass gob, at at least one moment and/or during at least one period after the glass gob has passed the inlet of the delivery system, by using an optical imaging device; and e) determining, based on the observing in step d), a glass gob observation result that includes a glass gob velocity, characterised in that the glass gob observation result is determined for predicting, based on at least the glass gob velocity of the glass gob observation result, a glass distribution of the glass product formed in the mould, and for controlling, based on at least the glass gob velocity of the glass gob observation result, depositing as in step a), guiding as in step b), and/or depositing as in step c), of a next glass gob that is formed later than the glass gob, wherein the glass gob observation result further includes at least one of a group of variables including a glass gob trajectory, a glass gob shape, and a glass gob orientation, and wherein predicting and controlling in step e) is further based on the at least one variable, wherein controlling, in step e), of guiding as in step b) of the next glass gob includes adjusting lubrication of the guiding means, and wherein controlling, in step e), of depositing as in step a) of the next glass gob includes adjusting a mutual position difference of the inlet and a formation position at which the glass gob is formed and/or includes adjusting air supply to an accelerator for the next glass gob, which accelerator is positioned before the inlet, and wherein controlling, in step e), of depositing as in step c) of the next glass gob includes adjusting a mutual position difference of the outlet and the opening of the mould. a) depositing the glass gob in the inlet of the delivery system; b) guiding the glass gob by using the guiding means towards the outlet of the delivery system; c) depositing the glass gob from the outlet of the delivery system in the opening of the mould; d) observing the glass gob, at at least one moment and/or during at least one period after the glass gob has passed the inlet of the delivery system, by using an optical imaging device; and e) determining, based on the observing in step d), a glass gob observation result that includes a glass gob velocity, characterised in that the glass gob observation result is determined for predicting, based on at least the glass gob velocity of the glass gob observation result, a glass distribution of the glass product formed in the mould, and for controlling, based on at least the glass gob velocity of the glass gob observation result, depositing as in step a), guiding as in step b), and/or depositing as in step c), of a next glass gob that is formed later than the glass gob, wherein the glass gob observation result further includes at least one of a group of variables including a glass gob trajectory, a glass gob shape, and a glass gob orientation, and wherein predicting and controlling in step e) is further based on the at least one variable, wherein controlling, in step e), of guiding as in step b) of the next glass gob includes adjusting lubrication of the guiding means, and wherein controlling, in step e), of depositing as in step a) of the next glass gob includes adjusting a mutual position difference of the inlet and a formation position at which the glass gob is formed and/or includes adjusting air supply to an accelerator for the next glass gob, which accelerator is positioned before the inlet, and wherein controlling, in step e), of depositing as in step c) of the next glass gob includes adjusting a mutual position difference of the outlet and the opening of the mould.