Context. High frame-rate imaging was employed to mitigate the effects of atmospheric turbulence (seeing) in observations of globular cluster Terzan 5. Aims. High-precision time-series photometry with the highest angular resolution so far has been obtained for the crowded central region of Terzan 5. Observations were carried out using ground-based telescopes, implementing ways to avoid saturation of the brightest stars in the field observed. Methods. The Electron-Multiplying Charge Coupled Device (EMCCD) camera installed at the Danish 1.54 m telescope at the ESO La Silla Observatory was used to produce thousands of short-exposure time images (ten images per second), which were stacked to produce the normal-exposure-time images (minutes). We employed difference image analysis in the stacked images to produce high-precision photometry using the DanDIA pipeline. Results. We analyzed the light curves of 1670 stars with 242 epochs in the crowded central region of Terzan 5 in order to statistically detect variable stars in the field observed. We present a possible visual counterpart outburst at the position of the pulsar J1748-2446N, and the visual counterpart light curve of the low-mass X-ray binary CX 3. Additionally, we present the discovery of four semiregular variables. We also present updated ephemerides and properties of the only RR Lyrae star previously known in the field covered by our observations in Terzan 5. Finally, we report a significant displacement of two sources by similar to 0.62 and 0.59 arcsec with respect to their positions in previous images available in the literature. C1 [Jaimes, R. Figuera; Catelan, M.] Millennium Inst Astrophys MAS, Nuncio Monsenor Sotero Sanz 100,Of 104, Santiago, Providencia, Chile. [Jaimes, R. Figuera; Catelan, M.] Pontificia Univ Catolica Chile, Fac Fis, Inst Astrofis, Av Vicuna Mackenna 4860, Santiago 7820436, Macul, Chile. [Jaimes, R. Figuera; Horne, K.; Dominik, M.] Univ St Andrews, Ctr Exoplanet Sci, Sch Phys & Astron, SUPA, St Andrews KY16 9SS, Scotland. [Skottfelt, J.] Open Univ, Ctr Elect Imaging, Dept Phys Sci, Milton Keynes MK7 6AA, England. [Snodgrass, C.; Bonavita, M.] Univ Edinburgh, Inst Astron, Royal Observ, Edinburgh EH9 3HJ, Scotland. [Jorgensen, U. G.] Univ Copenhagen, Niels Bohr Inst, Ctr ExoLife Sci, Oster Voldgade 5, DK-1350 Copenhagen, Denmark. [Southworth, J.] Keele Univ, Astrophys Grp, Keele ST5 5BG, Staffs, England. [Hundertmark, M.] Zentrum Astron Univ Heidelberg ZAH, Astron Rechen Inst, D-69120 Heidelberg, Germany. [Longa-Pena, P.] Univ Antofagasta, Ctr Astron, Ave Angamos 601, Antofagasta 1270300, Chile. [Sajadian, S.] Isfahan Univ Technol, Dept Phys, Esfahan 8415683111, Iran. [Tregolan-Reed, J.; Haikala, L.] Univ Atacama, Inst Astron & Ciencias Planetarias, Copayapu 485, Copiapo, Chile. [Hinse, T. C.] Univ Southern Denmark, Dept Phys Chem & Pharm, SDU Galaxy, Campusvej 55, DK-5230 Odense M, Denmark. [Andersen, M. I.] Univ Copenhagen, Niels Bohr Inst, Jagtvej 128, DK-2200 Copenhagen, Denmark. [Bozza, V.] Univ Salerno, Dipartimento Fis ER Caianiello, Via Giovanni Paolo II 132, I-84084 Fisciano, Italy. [Bozza, V.] Ist Nazl Fis Nucl Sez Napoli, Naples, Italy. [Burgdorf, M. J.] Univ Hamburg, Meteorol Inst, Fac Math Informat & Nat Sci, Dept Earth Sci, Bundesstr 55, D-20146 Hamburg, Germany. [Khalouei, E.] Seoul Natl Univ, Res Inst Basic Sci, Astron Res Ctr, 1 Gwanak ro, Seoul, South Korea. [Korhonen, H.] European Southern Observ ESO, Alonso Cordova 3107, Santiago, Vitacura, Chile. [Peixinho, N.] Univ Coimbra, Dept Fis, Inst Astrofis & Ciencias Espaco, P-3040004 Coimbra, Portugal. [Rabus, M.] Univ Catolica Santisima Concepcion, Fac Ingn, Dept Matemat & Fis Aplicadas, Alonso De Rivera 2850, Concepcion, Chile. [Rahvar, S.] Sharif Univ Technol, Dept Phys, POB 11155-9161, Tehran, Iran. C3 Pontificia Universidad Catolica de Chile; University of St Andrews; Open University - UK; University of Edinburgh; University of Copenhagen; Niels Bohr Institute; Keele University; Ruprecht Karls University Heidelberg; Universidad de Antofagasta; Isfahan University of Technology; Universidad de Atacama; University of Southern Denmark; University of Copenhagen; Niels Bohr Institute; University of Salerno; Istituto Nazionale di Fisica Nucleare (INFN); University of Hamburg; Seoul National University (SNU); Universidade de Coimbra; Universidad Catolica de la Santisima Concepcion; Sharif University of Technology