Ok with a webcam you don't require a flash, the webcam does not work with a flash it records the picture from the live feed video in your webcam you do need external light and we recommend a light color background curtain here is an example of my open booth and pictures of our event.
Understand, in order to take good photos, you need LIGHT...
a DSLR camera will have a flash built in ...
webcams need lighting set up to provide enough light
to get good photos. I have been using a webcam
for over 8 years and it needs a light to be on the area
where the guest/user(s) will be standing.
Attached are some sample photos and a photo of my booth with the light I use.