The dataset consists of three parts:
The first part is the recalibrated standard star catalog in the UBVRI bands from Clem & Landolt (2013) and Clem & Landolt (2016), containing approximately 47,000 standard stars with magnitudes roughly in the range of 12 < V < 22. Compared with the Gaia DR3 BP/RP spectra synthetic photometry (XPSP), the recalibrated catalog shows consistency levels of 48 mmag in the U band, 11 mmag in the B band, and 5–6 mmag in the VRI bands for stars with G < 16. This catalog also includes our quality assessment of several hundred Landolt (1992) photomultiplier based standard stars.

The second part is a catalog of approximately 5.4 million UBVRI standard stars generated using Gaia DR3 photometry and LAMOST DR12 stellar atmospheric parameters, combined through the Stellar Color Regression (SCR) method. Under typical conditions (V ≈ 14 and SNRG > 15), this catalog achieves consistency levels with XPSP of 28.1, 6.7, 3.5, 2.7, and 2.6 mmag in the UBVRI bands, respectively. Further tests indicate that the U-band precision of this catalog is generally superior to that of the XPSP method.

The third part provides the temperature- and extinction-dependent extinction coefficients in the UBVRI bands, identical to those listed in Table 2 of the paper (Huang et al. 2025b).

Descriptions of the individual columns in the first and second parts can be found in the corresponding readme files or in Tables 1 and 3 of our paper (Huang et al. 2025b).
For more detailed information, please refer to Huang et al. (2025b).