And there was nothing he could say were gunshot residue particles on swabs taken from David Bain.
Mr Henstchel who had 40 years with the ESR, is giving evidence on Day 18 of David Bain's retrial for the 1994 murders of his father Robin, mother Margaret, sisters Arawa and Laniet and younger brother Stephen.
He is the first of eight forensic scientists expected to give evidence for the Crown in this phase of the trial before Justice Graham Panckhurst and the jury.
Bain (37) denies killing his family, the defence case being that Robin shot his wife and three children before shooting himself after leaving a message for David on the family computer.
Mr Hentschel said today he found dirt and ''some possible blood'' in fingernail scrapings taken from Robin Bain's hands, but nothing else. There was not enough of what might have been blood for any testng. He described blood staining on the knee of Mr Bain's blue track pants and said he believed the blood dropped from a height when Mr Bain was standing. There was also blood on a green hat near Mr Bain's head where he lay on the floor and on the hood, front and left sleeve of a dark blue hooded sweatshirt he was wearing.
Luminol testing of Robin Bain's shoes and socks was negative but there were several spots of blood on David Bain's socks, the soles of which both gave a positive reaction to luminol.
