Visible crew/equipment: In the shot after Blackadder has read up Baldrick's votes a microphone is visible in the upper right corner. (00:18:15)
Visible crew/equipment: During the conversation between Blackadder and Baldrick, as Baldrick explains what he spent the £400,000 on, we can see the shadow from the boom mike moving on Blackadder's fur coat. (00:28:00)
Visible crew/equipment: When Baldrick is called upon to demonstrate the type of clothing required when visiting France, the edge of the scenery can be seen behind him on his right in the area he enters from.
Visible crew/equipment: In the first shot of the theatre play, you can see the boom mike quickly entering the picture to the left on the screen. (00:01:40)
Answer: The closest we ever get to knowing his first name is in series 3, when he claims it's "Sod Off". Blackadder asks him in series 3 where this came from, and he replies "Well, when I was a kid, living in the gutter, I'd go up to the other kids and say 'Hello, I'm Baldrick'. And they'd say, 'Yes, we know. Sod off, Baldrick.'" The S in this series is likely a reference to that, but it's not addressed, and given this Baldrick is clearly different from the series 3 Baldrick, we can't draw a direct link.
Shay