Comparison between derived photometric and spectroscopic redshifts for a sample of sources validated with Flag = 1–3. The dashed line shows the 1:1 relation. The dotted lines represent the photometric error δ_z/(1 + z) ∼ 0.047. We underestimate the photometric redshift for clusters at z >  0.5 due to a lack of z-band photometry in our follow-up. Therefore we assume these values as lower limits.