In relation to the UK border

My passing through the UK border
Passport out, cover bent back, the glow from the machine, sliding the page over the light, an awkward wait, unsure if I have done it correctly, a beep, the doors separating, the marks on the floor for my feet, aligning carefully, looking up at a digital reflection of myself, my eyes gazing into themselves, green, the second doors open, I walk through, my passport returns to my pocket