The DES 3x2pt analysis relied on robust redshift calibration, achieved through the combination of complementary techniques: self-organizing maps (SOMPZ), clustering redshifts, and shear ratios. I will discuss the successes and challenges of these methods, including how we addressed systematic uncertainties and developed efficient sampling strategies for cosmological inference. These achievements provide valuable insights for improving redshift calibration in next-generation surveys.
[Slides]