Continuity mistake: When Station 51 is dispatched to 'vehicle accident with injuries', Roy is in the locker room still getting into his uniform with his shirt untucked and belt undone when re runs into the apparatus bay, but in the next overhead shot Roy's uniform is on properly.
Continuity mistake: When Chet and John are by the sink talking about Chet's appearance on the news, in the reflection we can see the three lockers behind Chet, and in the next shot the door of the fourth locker is wide open, blocking the third locker, and we can see that it's open because of the poster that's taped to the inside of the fourth locker's door.
Visible crew/equipment: When Station 51 is dispatched to a vehicle accident in the canyon, en route there's a shot from the POV of the top of Engine 51, with the dome light in front of the camera, and the reflection of the covered camera, which is mounted on the engine's roof, is visible in the dome light's chrome surface.
Continuity mistake: When Johnny and Roy are with the boy who is in anaphylactic shock from the bee sting, Johnny's watch reads 2:25, then 2:35, and then 2:25 again.
Visible crew/equipment: After Cora is rescued from the cactus patch, when Harry annoys her and tells her to keep a stiff upper lip while she's lying on the gurney, the reflections of crew members and two reflector screens are visible on Harry's red bike helmet.
Visible crew/equipment: When Johnny and Roy help Cora crawl along the ladder from the cactus patch located in a secluded area, just as Johnny tells her to take it nice and slow, the camera moves a bit too far to the left and then shifts back to the right, but not before we are able to see a crew member, equipment and a large patio-style umbrella.
Visible crew/equipment: When Roy treks across the ladder to get to the woman in the cactus patch, the outlines of the lav mic transmitter and wire are visible at the back, right side of Roy's shirt. Then, when Johnny's on the Biophone with Rampart, the outline of the mic transmitter is visible at the back, left side of Johnny's shirt.
Continuity mistake: When 51's with Cora, the woman who was thrown into the middle of a cactus patch, they lower the ladder horizontally so it's beside her for the rescue, but while Roy treks across the ladder in the next shot of Cora the ladder is nowhere to be seen, then when Roy reaches her we see that it's indeed right beside her.
Continuity mistake: When Dixie walks over to the admitting desk and asks the nurse to stop what she's doing to set up treatment 4, the nurse places the black pen inside the metal folding clipboard and flips it closed, but in the next shot the pen is lying on top of the closed clipboard.
Visible crew/equipment: When Brackett walks out of his office, Betty walks over to him and asks if it's okay to go to Dixie for help with the nurses' scheduling problem, and the bulging outline of the mic transmitter is visible on the back of her uniform, directly under its zipper.
Visible crew/equipment: When deciding how to rescue Cora from the middle of the cactus patch, Mike parks Engine 51 at the side of the road, beside the hill with the cactus. During the rescue there are closeups of Cora's husband standing beside Engine 51, and we see other things reflected on the engine instead of just the side of the hill. Additionally, his position in the closeups differs from where he stands in the wideshots.
Visible crew/equipment: While Roy is hanging off the side of the building with the second victim, Johnny's trying to tie off the swaying sign, then after he asks for some slack the second time, there's an overhead shot from the roof, and we can see the shadow of the camera and a bit of a crew member, at the bottom of the screen. Then a few shots later, from the same POV, we still see the camera's shadow, and we also see the leg of a crew member (white sneaker and dark pants) walk into the shot and back out, at the left of the screen.
Continuity mistake: When 51's guys get to the roof of the building with the swaying sign, Marco places the silver hose roller on the roof edge, but when Captain Stanley and Stevie's father lean over the edge to talk to Stevie, the second larger hose roller is already in place near the silver hose roller, even though the second one hasn't been brought to the roof yet by Engine 95's guys.
Visible crew/equipment: At the scene of the swaying sign accident, when Roy and Johnny get the gear out of the squad the outlines of the mic transmitters are visible on the left side of Johnny's shirt and right side of Roy's. Once they're on the roof both of the mic transmitters' outlines are on the right sides of their shirts, and later when Roy and Gil are pulled up onto the roof, the bulging outline is visible again at Roy's right side.
Daisy's Pick Blind Date - S4-E7
Visible crew/equipment: After rescuing the injured man from the burning theater, when Roy and John are on the roof getting the stokes with the victim onto 36's snorkel, we can see a crew member's arm/hand, wearing a white patterned long sleeve shirt, standing at the right side of the screen.
Daisy's Pick Blind Date - S4-E7
Revealing mistake: When John and Roy bring the hypothermic patient into treatment 3, Morton uses the laryngoscope, but the problem here is that when it's placed we can see that the laryngoscope is actually at the side of the patient's face.
Daisy's Pick Blind Date - S4-E7
Visible crew/equipment: When Roy and Johnny are with the hypothermic refrigeration engineer, the outlines of the mic transmitter and wire are visible on the back, left side of Johnny's shirt. Note that when Johnny and Roy are in the ambulance with the patient, Johnny is not wearing the lavalier transmitter and wire anymore.
Daisy's Pick Blind Date - S4-E7
Other mistake: When Squad 51 is dispatched to "man needs assistance", in the exterior shot as the squad rolls out of the apparatus bay we can see Engine 51 still inside the bay, but the real Station 127's engine is parked right beside the station house.
Daisy's Pick Blind Date - S4-E7
Visible crew/equipment: After Brackett's examination of Jerry, the unconscious 3 year old, when he goes to the waiting room and introduces himself to Jerry's parents, the top of set can be seen over treatment 1.
Daisy's Pick Blind Date - S4-E7
Other mistake: When dispatched to the fire in the theater, the companies called are Station 51, Engine 85, and Station 36, but at the scene of the fire we see Engine 9 roll up and also see firemen with 19 on their helmets. These are shots from previous episodes including 3x7, "Promotion", when Roy and John rescue the security guard at the structure fire.
Answer: I believe you are speaking of the old man, Mr. Wilson. He's played by J. Pat O'Malley.
Bishop73
Correct, it was J. Pat O'Malley...he also played the grandfather with his grandson when their rocket exploded, and also played "Old Bill" in the episode with Ann Prentiss, where Gage saves the little girl from the burning tree house, and her mother falls in love with him.