Robin/Jason is wearing handcuffs when the warehouse explodes. When Batman pulls the body out of the rubble the handcuffs are gone.
Towards the end, when Red Hood takes off his mask, it's at his feet, but in the long shot it is missing.
During the big fight on the roof, Red Hood takes off Batman's belt, disabling his abilities to use his weapons. Leaving him with only his fist. Yet, when Batman and Red Hood have there final fight, there is a brief cut and Batman is seen wearing his yellow belt very briefly. There is no indication that Batman ever put on his belt, and the rest of the sequence he has no belt.
The bathroom in which Batman and the Red Hood fight in has no door to it, until Batman makes his own door by punching the Red Hood through a wall.
When Bruce Wayne is reminiscing about the past Robin (Jason Todd) he looks at the old robin suit that is behind glass in the bat cave. The cape of the suit is visible behind the R symbol of the suit. When Bruce is done reminiscing the cape is blocking the R symbol.