Catalyzes the conversion of divinyl chlorophyllide to monovinyl chlorophyllide. Reduces the 8-vinyl group of the tetrapyrrole to an ethyl group using NADPH as the reductant. Can use (3,8-divinyl)-chlorophyllide a (DV-Chlidea) > (3,8-divinyl)-chlorophyll a (DV-Chla) > (3,8-divinyl)-protochlorophyllide a (DV-Pchlidea) > (3,8-divinyl)-magnesium-protoporphyrin IX monomethyl ester (DV-MPE) > (3,8-divinyl)-magnesium-protoporphyrin IX (DV-Mg-Proto) as substrates. NADP(+) + protochlorophyllide a = 3,8-divinyl protochlorophyllide a + H(+) + NADPH Porphyrin-containing compound metabolism; chlorophyll biosynthesis.