Visible crew/equipment: When Nina's just been shot, and makes it to the barn to call CTU (around 7.10am), while she's speaking on the phone there's a cameraman visible on the right hand side (DVD). (00:12:40)
Revealing mistake: When Syd's Dad rescues her in the car park, he starts shooting at the other car. After firing one shot the slide of his gun locks back (indicating it's out of bullets), but when the angle changes he carries on firing with no problems. (00:43:20)
Episode XCII - S5-E1
Deliberate mistake: Jack stops his motorbike beside a stream, and Jack's weapon strap crosses over his left shoulder when he walks over to have a drink. The problem is when we see Jack's reflection in the water, his image is not reversed; note the strap is still crossing over Jack's left shoulder. (00:07:20)