Is it permissible to keep a photograph of the deceased when saying Kaddish?
I have Yahrtzeit for my father this week and thought it would help me to focus connect with him more than just keeping him in my thoughts.
Kaddish is the way in which the Hashem's radiance, partially diminshed through the passing of the departed, is restored.
Kaddish is for the Living
Remarkably, the Mourner's Kaddish does not mention death, nor make any reference to the deceased. It is directed, instead, at the living.
The Kaddish affirms G‑d's justice and speaks of the value of life. It states that G‑d is the Creator of the world and that He rules it. Kaddish also states that there will be an Era of Moshiach, when all illness and suffering will cease, and requests that this time be ushered in during our lifetime.
Further, it praises G‑d's name and describes His glory.
Our sages teach that every Jewish person reveals a particular expression of G‑dliness in this world. Once he or she passes away, G‑d's radiance is "diminished" somewhat in this world. When Kaddish is recited, it restores this radiance and brings additional glory to G‑d's name in this world.
It seems therefore that you do not need to “to focus connect with him more than just keeping him in my thoughts” when saying kaddish.
Rather you need to acknowledge G-d's justice and hope for the restoration of that part of G-d's radiance which your father provided while he was on this earth.
IMHO a picture might detract from that purpose.