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We present high‐resolution  I ‐band imaging of the core of the globular cluster M15 obtained at the 2.5‐m Nordic Optical Telescope with FastCam, a low readout noise L3CCD‐based instrument. Short exposure times (30 ms) were used to record 200 000 images (512 × 512 pixels each) over a period of 2 h and 43 min. The lucky imaging technique was then applied to generate a final image of the cluster centre with full width at half‐maximum ∼0.1 arcsec and 13 × 13 arcsec 2  field of view. We obtained a catalogue of objects in this region with a limiting magnitude of  I = 19.5.  I ‐band photometry and astrometry are reported for 1181 stars. This is the deepest  I ‐band observation of the M15 core at this spatial resolution. Simulations show that crowding is limiting the completeness of the catalogue. At shorter wavelengths, a similar number of objects have been reported using  Hubble Space Telescope (HST )/Wide Field Planetary Camera observations of the same field. The cross‐match with the available  HST  catalogues allowed us to produce colour–magnitude diagrams where we identify new blue straggler star candidates and previously known stars of this class.

High‐resolution optical imaging of the core of the globular cluster M15 with FastCam