you won't be in the video

[Winwin2011]

I want to use a mobile phone to record how the teacher read a poem. I just want to record his voice. I won't let the teacher in the video i.e no picture for him. Can anybody teach me how to ask the teacher emphazing that he won't be in the video? If I say "I won't let you in the video", is it odd?

Thanks.

[Barb_D]

Can I do a voice-recording of you reading this poem?