Obsurveyor

I have a Vivotek IP7138 IP camera and a Tamron 13VM308AS lens. This lens is specifically mentioned on Vivotek's website as an accessory for the 7138. When I attempted to put the lens on the camera, I found that the camera body has a much larger ring than the lens. It seems(I measured as best I could with a caliper) that the camera body has a 30mm ring and the Tamron has a 25mm ring. So it seems I need a 30mm to 25mm step down adapter. First of all, for anyone who has worked with this camera before and changed the lens, are these sizes and is this information correct? I used the included hex key to remove the original lens from the camera. The 7138 did include an adapter ring but I think it is just a C mount to CS mount adapter. What I find odd is that the 7138 cannot accept the Tamron right out of the box, even though they mention it on their website. It is also not able to connect directly to this adapter ring either. Unless I can somehow remove the ring from the factory lens and that has the 25mm connection I need for the Tamron, it appears I need a third part to make it all work. I have tried emailing Vivotek technical support, but I have only received an automated reply.

Are you or anyone reading familiar with how to change the lens on the Vivotek IP7138? I just got a Tamron 13VM308AS lens(which is listed on Vivotek's website) that I would like to put on my 7138 but the camera body seems to require a much larger ring than the one on the Tamron. The 7138 included some kind of adapter but it is much too small.