Hi Tony,
Is there anything on the webcam to say what brand or model it is?
Also can you post a pick of it as that may help some of the more experienced guys solve the problem.
Another point ( AS i Have had same problem with light) If you are not dead centre aligned a bright object EG the moon or jupiter they throw enough light off ,you think they are there but they are actually outside the field of view.
Just a suggestion as it has happened to me,LOL
Hope this helps in some way.
Cheers,
Duncan
