Congratulations to our top entrant Victoria Buchan who captured the nuts and bolts of a windpump as part of our energy project. See our other favourites in our online gallery here.

This month, we would like you to focus your lenses on images relating to pressure, whether it’s a steam engine or a celebratory bottle of champagne – but don’t forget to let us know how you took the shot.

You can share your photos by clicking on the blue ‘Contribute’ button on this article. You can also use the GuardianWitness smartphone app or the new Guardian app and search for ‘GuardianWitness assignments’.

Our favourite will be seen in print in the October issue of Observer Tech Monthly while the best of the rest will appear in an online gallery.

Closing date is 1 October 2014.

• GuardianWitness is the home of user-generated content on the Guardian. Contribute your video, pictures and stories, and browse news, reviews and creations submitted by others. Posts will be reviewed prior to publication on GuardianWitness, and the best pieces will feature on the Guardian site.