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tokens: the estimates of physical parameters based on the spectral energy distribution (SED) fitting tool. The final results of this work are summarized in Sect. 6 . 2. Observations, data reduction, and photometric and astrometric calibrations The observations were carried out using the 0.81 m (32′′) Tenagra telescope, which uses a science camera with 2048 × 2048 pixels having an effective plate scale of ∼0.98′′ per pixel and a field of view of 16.8 × 16.8 arcmin 2 . The images in the V R I filters were acquired between May 2012 and June 2013 over 90 nights, often three times each night but within one hour, while the B -band images were taken only over two nights. There are only 5 frames in B and around 250 frames in V R I , taken with exposures varying from 420s in B to 90s in I . Calibration images (bias and flats) were obtained nightly and the pre-processing of images (bias subtraction, flat-fielding, etc.) was done in IRAF 1 . Finally, 760 scientifically useful images were used to perform photometry. Figure 1 shows the color-composite image of the selected star-forming region towards IC 5070 obtained using the V R I images taken on the first night. Fig. 1. Color composite image of the young star-forming region towards Pelican Nebula obtained using the V R I -band images. The cyan circles represent the location of the variable stars. The time-series photometry of the processed images was performed using DAOPHOT/ALLSTAR ( Stetson 1987 ) and DAOMATCH/DAOMASTER ( Stetson 1993 ) routines. In this process all sources above the 4 σ threshold in each image are selected and the aperture photometry is obtained with a radius of 4 pixels. The point spread function (PSF) is determined from 20 bright and isolated stars in each image, which is used to perform the PSF photometry using ALLSTAR on all images. The frames taken on the first night are selected as the master image in each filter and the PSF photometry are used as input to DAOMATCH to derive accurate frame-to-frame coordinate transformations. These transformations are used to obtain the corrected magnitudes of the stars relative to their magnitudes in the master image for all frames using DAOMASTER. The photometry includes 1307 sources with more than 50 observations in the target field, and over 1000 stars with both V - and I -band measurements. Within our target region, optical counterparts of 77 of the ∼135 YSOs from Rebull et al. (2011) were found within 3′′ matching radius in our photometry. The photometric calibration to Landolt filters ( Landolt 2009 ) was performed using the standard star photometry carried out on the same night as the master frame. The standard transformation equations are: where, b , v , r , i are instrumental magnitudes; B , V , R , I are standard magnitudes; and X b , X v , X r , X i are the airmass in the B V R I filters. The maximum uncertainty of these coefficients and the dispersion in these relations are on the order of 0.02 magnitude. If the star is observed in one