The photosensing ability of two blue-absorbing dendrimers is presented. Bulk heterojunction photodetectors were fabricated by spin-coating a blend solution of quinquethiophene (pentathiophene) cored conjugated dendrimers and [6,6]-phenyl-C61-butyric acid methyl ester (PCBM). The photoresponse characterized under monochromatic illumination at 442 nm increases linearly with a dynamic range of ∼105. The response approaches that required for spectral selectivity for camera applications, and the external quantum efficiency of the photodetectors reached up to 22.5% at 435 nm.