In R. v. Inksetter, the Court of Appeal for Ontario has signalled that while probation may be a component of a sentence for a child pornography offence, probation (even a relatively onerous probation) is very unlikely to reduce what is generally required by imprisonment to satisfy the primary sentencing objectives of deterrence and denunciation.
See R. v. Inksetter, 2018 ONCA 474, at para. 20.
Denunciation and general deterrence are the primary principles of sentencing for offences involving child pornography:
R. v. D.G.F., 2010 ONCA 27 (CanLII), 98 O.R. (3d) 241, at paras. 21-22, 30; R. v. Nisbet, 2011 ONCA 26 (CanLII),  O.J. No. 101, at para. 3; R. v. E.O., 2003 CanLII 2017 (ON CA),  O.J. No. 563, at para. 7; R. v. Stroempl, 1995 CanLII 2283 (ON CA),  O.J. No. 2772, at para. 9.
Probation has traditionally been viewed as a rehabilitative sentencing tool. It does not seek to serve the need for denunciation or general deterrence.
R. v. Proulx, 2000 SCC 5 (CanLII),  1 S.C.R. 61, at p. 87.
The courts have very few options other than imprisonment to achieve the objectives of denunciation and general deterrence.
R. v. Lacasse, 2015 SCC 64 (CanLII),  3 S.C.R. 1089, at para. 6.