See, also, R. v. Ramage,  O.J. No. 2970, 2010 ONCA 488, 257
C.C.C. (3d) 261, at para. 72.
 There is particular reason for deference in this case. While
the appellant pleaded guilty, and the judge did not hear evidence as
to guilt, he heard evidence on sentencing from the investigating
officer, a member of the OPP’s Child Sexual Exploitation Unit,
concerning the search to identify the three child victims, the identification of the appellant and the discovery of the child pornography
on his computers. The officer testified about the nature and extent
of distribution of child pornography on the Internet, including the
“S series”, the location of secret and encrypted websites and user
exchange groups and the existence of sadistic and degrading websites devoted to made-to-order sexual abuse of very young children
and babies. The officer also testified about the appellant’s involvement in this world of Internet child pornography where he aspired
to be, and apparently was, a respected producer.
 The sentencing judge also saw with his own eyes a selection
of photographs and video clips, explained by the investigating
officer, to demonstrate the abuse the appellant perpetrated on the
three victims. This was the child pornography which he himself
produced and distributed on the Internet. The judge also observed
a selection of the unrelated sadistic, intrusive and degrading child
pornography that was part of the appellant’s collection.
 In R. v. Kwok,  O.J. No. 457, 2007 CanLII 2942
(S.C.J.), at para. 48, Molloy J. observed, in reference to sadistic
child pornography, that “[w]hile the description in words of such
disturbing images is shocking, nobody can fully appreciate the
sickening horror of such pornography without actually looking at
it”. Having seen and heard this evidence, the trial judge had an
appreciation of the evidence that this court does not have.
 One of the leading cases concerning deference in sentencing matters is the Supreme Court’s decision in R. v. M. (L.), 
2 S.C.R. 163,  S.C.J. No. 31, 2008 SCC 31, a case that bears
some similarity to this. In M. (L.), the accused was convicted of
sexually assaulting his four-year-old daughter and of making,
distributing and possessing child pornography. His collection of
5,300 pictures and 540 videos of child pornography included many
images of his sexual abuse of his daughter. He distributed the
pornography for profit on the Internet. The trial judge imposed the
maximum ten-year sentence for sexual assault and a consecutive
sentence on the charges of possessing, making and distributing
child pornography, which resulted in a global sentence of 15 years.
The Quebec Court of Appeal reduced the global sentence from 15
to nine years. In restoring the sentence imposed by the trial judge,