Figure 3.
![Left-hand panel: a Hess diagram (logarithmically scaled) of the CMD for all stars in the CFHT/MegaCam field. Mean errors as a function of magnitude are shown. Regions of significant foreground and background contamination are labelled with the source of contamination. Right-hand panel: blue points show the CMD of all stars within 4rs from the centre of Sag DIG. The green isochrone traces an RGB, with an age of 6 Gyr and [Fe/H] = −2.2 dex. The purple isochrones are for younger populations with ages 50 Myr (dashed) and 500 Myr (solid) and a metallicity of [M/H] = −2.0 dex. All isochrones are from the PARSEC isochrone set (Bressan et al. 2012) and have been adjusted to the distance of Sag DIG as determined in Section 3.1.](https://oup.silverchair-cdn.com/oup/backfile/Content_public/Journal/mnras/458/2/10.1093_mnras_stw257/3/stw257fig3.jpeg?Expires=1750466225&Signature=Z~ag~oYUAtEb5AcxU0UyPGepiMjTlZsi8CcmyGX1TByHKqqaLAm~Y2mYWlD2K6JW0WR6NU7CcHGmah8~3NsTGJEuGnaT4jmIXXs~CY9O8k5zLOL46ZvUXhZ8fafxsw~1HNC6JWcLycGuaqdtl~3Yp2Dtsj6V3EdyGXNBEA3DEcISayB2yetdFcrq3HfhGTHGzmjGrW9TPreQLdFJdgPywzVeiGHh~B3h2HKHGc7128TXgBPcdY7iBI3dU1gB3k1C6Na5Nze7Iy~dAHC6B1DM0PGD-OC-r9FYua50FPsaNYz166Goo7rCfrQF5pWlGIm7bXspz3RUIZ~VbYArWeTdgA__&Key-Pair-Id=APKAIE5G5CRDK6RD3PGA)
Left-hand panel: a Hess diagram (logarithmically scaled) of the CMD for all stars in the CFHT/MegaCam field. Mean errors as a function of magnitude are shown. Regions of significant foreground and background contamination are labelled with the source of contamination. Right-hand panel: blue points show the CMD of all stars within 4rs from the centre of Sag DIG. The green isochrone traces an RGB, with an age of 6 Gyr and [Fe/H] = −2.2 dex. The purple isochrones are for younger populations with ages 50 Myr (dashed) and 500 Myr (solid) and a metallicity of [M/H] = −2.0 dex. All isochrones are from the PARSEC isochrone set (Bressan et al. 2012) and have been adjusted to the distance of Sag DIG as determined in Section 3.1.
